Commit | Line | Data |
---|---|---|
b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
cf45b752 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
b3b94faa DT |
4 | * |
5 | * This copyrighted material is made available to anyone wishing to use, | |
6 | * modify, copy, or redistribute it subject to the terms and conditions | |
e9fc2aa0 | 7 | * of the GNU General Public License version 2. |
b3b94faa DT |
8 | */ |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/spinlock.h> | |
b3b94faa DT |
13 | #include <linux/buffer_head.h> |
14 | #include <linux/delay.h> | |
15 | #include <linux/sort.h> | |
16 | #include <linux/jhash.h> | |
d0dc80db | 17 | #include <linux/kallsyms.h> |
5c676f6d | 18 | #include <linux/gfs2_ondisk.h> |
24264434 | 19 | #include <linux/list.h> |
fee852e3 | 20 | #include <linux/wait.h> |
95d97b7d | 21 | #include <linux/module.h> |
b3b94faa | 22 | #include <asm/uaccess.h> |
7c52b166 RP |
23 | #include <linux/seq_file.h> |
24 | #include <linux/debugfs.h> | |
8fbbfd21 SW |
25 | #include <linux/kthread.h> |
26 | #include <linux/freezer.h> | |
c4f68a13 BM |
27 | #include <linux/workqueue.h> |
28 | #include <linux/jiffies.h> | |
bc015cb8 SW |
29 | #include <linux/rcupdate.h> |
30 | #include <linux/rculist_bl.h> | |
31 | #include <linux/bit_spinlock.h> | |
a245769f | 32 | #include <linux/percpu.h> |
4506a519 | 33 | #include <linux/list_sort.h> |
b3b94faa DT |
34 | |
35 | #include "gfs2.h" | |
5c676f6d | 36 | #include "incore.h" |
b3b94faa DT |
37 | #include "glock.h" |
38 | #include "glops.h" | |
39 | #include "inode.h" | |
b3b94faa DT |
40 | #include "lops.h" |
41 | #include "meta_io.h" | |
42 | #include "quota.h" | |
43 | #include "super.h" | |
5c676f6d | 44 | #include "util.h" |
813e0c46 | 45 | #include "bmap.h" |
63997775 SW |
46 | #define CREATE_TRACE_POINTS |
47 | #include "trace_gfs2.h" | |
b3b94faa | 48 | |
6802e340 | 49 | struct gfs2_glock_iter { |
ba1ddcb6 SW |
50 | int hash; /* hash bucket index */ |
51 | unsigned nhash; /* Index within current bucket */ | |
52 | struct gfs2_sbd *sdp; /* incore superblock */ | |
53 | struct gfs2_glock *gl; /* current glock struct */ | |
54 | loff_t last_pos; /* last position */ | |
7c52b166 RP |
55 | }; |
56 | ||
b3b94faa DT |
57 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
58 | ||
6802e340 | 59 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target); |
c4f68a13 | 60 | |
7c52b166 | 61 | static struct dentry *gfs2_root; |
c4f68a13 | 62 | static struct workqueue_struct *glock_workqueue; |
b94a170e | 63 | struct workqueue_struct *gfs2_delete_workqueue; |
97cc1025 SW |
64 | static LIST_HEAD(lru_list); |
65 | static atomic_t lru_count = ATOMIC_INIT(0); | |
eb8374e7 | 66 | static DEFINE_SPINLOCK(lru_lock); |
08bc2dbc | 67 | |
b6397893 | 68 | #define GFS2_GL_HASH_SHIFT 15 |
087efdd3 SW |
69 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
70 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) | |
71 | ||
bc015cb8 | 72 | static struct hlist_bl_head gl_hash_table[GFS2_GL_HASH_SIZE]; |
04b933f2 | 73 | static struct dentry *gfs2_root; |
087efdd3 | 74 | |
b3b94faa DT |
75 | /** |
76 | * gl_hash() - Turn glock number into hash bucket number | |
77 | * @lock: The glock number | |
78 | * | |
79 | * Returns: The number of the corresponding hash bucket | |
80 | */ | |
81 | ||
b8547856 SW |
82 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
83 | const struct lm_lockname *name) | |
b3b94faa DT |
84 | { |
85 | unsigned int h; | |
86 | ||
cd915493 | 87 | h = jhash(&name->ln_number, sizeof(u64), 0); |
b3b94faa | 88 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
b8547856 | 89 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
b3b94faa DT |
90 | h &= GFS2_GL_HASH_MASK; |
91 | ||
92 | return h; | |
93 | } | |
94 | ||
bc015cb8 SW |
95 | static inline void spin_lock_bucket(unsigned int hash) |
96 | { | |
1879fd6a | 97 | hlist_bl_lock(&gl_hash_table[hash]); |
bc015cb8 | 98 | } |
b3b94faa | 99 | |
bc015cb8 SW |
100 | static inline void spin_unlock_bucket(unsigned int hash) |
101 | { | |
1879fd6a | 102 | hlist_bl_unlock(&gl_hash_table[hash]); |
bc015cb8 | 103 | } |
b3b94faa | 104 | |
fc0e38da | 105 | static void gfs2_glock_dealloc(struct rcu_head *rcu) |
b3b94faa | 106 | { |
bc015cb8 | 107 | struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu); |
b3b94faa | 108 | |
dba2d70c | 109 | if (gl->gl_ops->go_flags & GLOF_ASPACE) { |
bc015cb8 | 110 | kmem_cache_free(gfs2_glock_aspace_cachep, gl); |
dba2d70c | 111 | } else { |
4e2f8849 | 112 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 113 | kmem_cache_free(gfs2_glock_cachep, gl); |
dba2d70c | 114 | } |
fc0e38da SW |
115 | } |
116 | ||
117 | void gfs2_glock_free(struct gfs2_glock *gl) | |
b3b94faa DT |
118 | { |
119 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
b3b94faa | 120 | |
fc0e38da | 121 | call_rcu(&gl->gl_rcu, gfs2_glock_dealloc); |
bc015cb8 SW |
122 | if (atomic_dec_and_test(&sdp->sd_glock_disposal)) |
123 | wake_up(&sdp->sd_glock_wait); | |
b3b94faa DT |
124 | } |
125 | ||
126 | /** | |
127 | * gfs2_glock_hold() - increment reference count on glock | |
128 | * @gl: The glock to hold | |
129 | * | |
130 | */ | |
131 | ||
b94a170e | 132 | void gfs2_glock_hold(struct gfs2_glock *gl) |
b3b94faa | 133 | { |
d8348de0 | 134 | GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0); |
16feb9fe | 135 | atomic_inc(&gl->gl_ref); |
b3b94faa DT |
136 | } |
137 | ||
8ff22a6f BM |
138 | /** |
139 | * demote_ok - Check to see if it's ok to unlock a glock | |
140 | * @gl: the glock | |
141 | * | |
142 | * Returns: 1 if it's ok | |
143 | */ | |
144 | ||
145 | static int demote_ok(const struct gfs2_glock *gl) | |
146 | { | |
147 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
148 | ||
149 | if (gl->gl_state == LM_ST_UNLOCKED) | |
150 | return 0; | |
f42ab085 | 151 | if (!list_empty(&gl->gl_holders)) |
8ff22a6f BM |
152 | return 0; |
153 | if (glops->go_demote_ok) | |
154 | return glops->go_demote_ok(gl); | |
155 | return 1; | |
156 | } | |
157 | ||
bc015cb8 | 158 | |
29687a2a SW |
159 | void gfs2_glock_add_to_lru(struct gfs2_glock *gl) |
160 | { | |
161 | spin_lock(&lru_lock); | |
162 | ||
163 | if (!list_empty(&gl->gl_lru)) | |
164 | list_del_init(&gl->gl_lru); | |
165 | else | |
166 | atomic_inc(&lru_count); | |
167 | ||
168 | list_add_tail(&gl->gl_lru, &lru_list); | |
627c10b7 | 169 | set_bit(GLF_LRU, &gl->gl_flags); |
29687a2a SW |
170 | spin_unlock(&lru_lock); |
171 | } | |
172 | ||
4043b886 | 173 | static void __gfs2_glock_remove_from_lru(struct gfs2_glock *gl) |
f42ab085 | 174 | { |
f42ab085 SW |
175 | if (!list_empty(&gl->gl_lru)) { |
176 | list_del_init(&gl->gl_lru); | |
177 | atomic_dec(&lru_count); | |
178 | clear_bit(GLF_LRU, &gl->gl_flags); | |
179 | } | |
4043b886 SW |
180 | } |
181 | ||
182 | static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl) | |
183 | { | |
184 | spin_lock(&lru_lock); | |
185 | __gfs2_glock_remove_from_lru(gl); | |
f42ab085 SW |
186 | spin_unlock(&lru_lock); |
187 | } | |
188 | ||
8ff22a6f BM |
189 | /** |
190 | * gfs2_glock_put_nolock() - Decrement reference count on glock | |
191 | * @gl: The glock to put | |
192 | * | |
193 | * This function should only be used if the caller has its own reference | |
194 | * to the glock, in addition to the one it is dropping. | |
195 | */ | |
196 | ||
b94a170e | 197 | void gfs2_glock_put_nolock(struct gfs2_glock *gl) |
8ff22a6f BM |
198 | { |
199 | if (atomic_dec_and_test(&gl->gl_ref)) | |
200 | GLOCK_BUG_ON(gl, 1); | |
8ff22a6f BM |
201 | } |
202 | ||
b3b94faa DT |
203 | /** |
204 | * gfs2_glock_put() - Decrement reference count on glock | |
205 | * @gl: The glock to put | |
206 | * | |
207 | */ | |
208 | ||
bc015cb8 | 209 | void gfs2_glock_put(struct gfs2_glock *gl) |
b3b94faa | 210 | { |
bc015cb8 SW |
211 | struct gfs2_sbd *sdp = gl->gl_sbd; |
212 | struct address_space *mapping = gfs2_glock2aspace(gl); | |
b3b94faa | 213 | |
4043b886 SW |
214 | if (atomic_dec_and_lock(&gl->gl_ref, &lru_lock)) { |
215 | __gfs2_glock_remove_from_lru(gl); | |
216 | spin_unlock(&lru_lock); | |
bc015cb8 SW |
217 | spin_lock_bucket(gl->gl_hash); |
218 | hlist_bl_del_rcu(&gl->gl_list); | |
219 | spin_unlock_bucket(gl->gl_hash); | |
6802e340 | 220 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); |
bc015cb8 SW |
221 | GLOCK_BUG_ON(gl, mapping && mapping->nrpages); |
222 | trace_gfs2_glock_put(gl); | |
223 | sdp->sd_lockstruct.ls_ops->lm_put_lock(gl); | |
b3b94faa | 224 | } |
b3b94faa DT |
225 | } |
226 | ||
b3b94faa DT |
227 | /** |
228 | * search_bucket() - Find struct gfs2_glock by lock number | |
229 | * @bucket: the bucket to search | |
230 | * @name: The lock name | |
231 | * | |
232 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
233 | */ | |
234 | ||
37b2fa6a | 235 | static struct gfs2_glock *search_bucket(unsigned int hash, |
899be4d3 | 236 | const struct gfs2_sbd *sdp, |
d6a53727 | 237 | const struct lm_lockname *name) |
b3b94faa DT |
238 | { |
239 | struct gfs2_glock *gl; | |
bc015cb8 | 240 | struct hlist_bl_node *h; |
b3b94faa | 241 | |
bc015cb8 | 242 | hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) { |
b3b94faa DT |
243 | if (!lm_name_equal(&gl->gl_name, name)) |
244 | continue; | |
899be4d3 SW |
245 | if (gl->gl_sbd != sdp) |
246 | continue; | |
bc015cb8 SW |
247 | if (atomic_inc_not_zero(&gl->gl_ref)) |
248 | return gl; | |
b3b94faa DT |
249 | } |
250 | ||
251 | return NULL; | |
252 | } | |
253 | ||
6802e340 SW |
254 | /** |
255 | * may_grant - check if its ok to grant a new lock | |
256 | * @gl: The glock | |
257 | * @gh: The lock request which we wish to grant | |
258 | * | |
259 | * Returns: true if its ok to grant the lock | |
260 | */ | |
261 | ||
262 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) | |
263 | { | |
264 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); | |
265 | if ((gh->gh_state == LM_ST_EXCLUSIVE || | |
266 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) | |
267 | return 0; | |
268 | if (gl->gl_state == gh->gh_state) | |
269 | return 1; | |
270 | if (gh->gh_flags & GL_EXACT) | |
271 | return 0; | |
209806ab SW |
272 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
273 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) | |
274 | return 1; | |
275 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) | |
276 | return 1; | |
277 | } | |
6802e340 SW |
278 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
279 | return 1; | |
280 | return 0; | |
281 | } | |
282 | ||
283 | static void gfs2_holder_wake(struct gfs2_holder *gh) | |
284 | { | |
285 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
286 | smp_mb__after_clear_bit(); | |
287 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); | |
288 | } | |
289 | ||
d5341a92 SW |
290 | /** |
291 | * do_error - Something unexpected has happened during a lock request | |
292 | * | |
293 | */ | |
294 | ||
295 | static inline void do_error(struct gfs2_glock *gl, const int ret) | |
296 | { | |
297 | struct gfs2_holder *gh, *tmp; | |
298 | ||
299 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
300 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
301 | continue; | |
302 | if (ret & LM_OUT_ERROR) | |
303 | gh->gh_error = -EIO; | |
304 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) | |
305 | gh->gh_error = GLR_TRYFAILED; | |
306 | else | |
307 | continue; | |
308 | list_del_init(&gh->gh_list); | |
309 | trace_gfs2_glock_queue(gh, 0); | |
310 | gfs2_holder_wake(gh); | |
311 | } | |
312 | } | |
313 | ||
6802e340 SW |
314 | /** |
315 | * do_promote - promote as many requests as possible on the current queue | |
316 | * @gl: The glock | |
317 | * | |
813e0c46 SW |
318 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
319 | * if a type specific operation is underway. | |
6802e340 SW |
320 | */ |
321 | ||
322 | static int do_promote(struct gfs2_glock *gl) | |
55ba474d HH |
323 | __releases(&gl->gl_spin) |
324 | __acquires(&gl->gl_spin) | |
6802e340 SW |
325 | { |
326 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
327 | struct gfs2_holder *gh, *tmp; | |
328 | int ret; | |
329 | ||
330 | restart: | |
331 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
332 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
333 | continue; | |
334 | if (may_grant(gl, gh)) { | |
335 | if (gh->gh_list.prev == &gl->gl_holders && | |
336 | glops->go_lock) { | |
337 | spin_unlock(&gl->gl_spin); | |
338 | /* FIXME: eliminate this eventually */ | |
339 | ret = glops->go_lock(gh); | |
340 | spin_lock(&gl->gl_spin); | |
341 | if (ret) { | |
813e0c46 SW |
342 | if (ret == 1) |
343 | return 2; | |
6802e340 SW |
344 | gh->gh_error = ret; |
345 | list_del_init(&gh->gh_list); | |
63997775 | 346 | trace_gfs2_glock_queue(gh, 0); |
6802e340 SW |
347 | gfs2_holder_wake(gh); |
348 | goto restart; | |
349 | } | |
350 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 351 | trace_gfs2_promote(gh, 1); |
6802e340 SW |
352 | gfs2_holder_wake(gh); |
353 | goto restart; | |
354 | } | |
355 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 356 | trace_gfs2_promote(gh, 0); |
6802e340 SW |
357 | gfs2_holder_wake(gh); |
358 | continue; | |
359 | } | |
360 | if (gh->gh_list.prev == &gl->gl_holders) | |
361 | return 1; | |
d5341a92 | 362 | do_error(gl, 0); |
6802e340 SW |
363 | break; |
364 | } | |
365 | return 0; | |
366 | } | |
367 | ||
6802e340 SW |
368 | /** |
369 | * find_first_waiter - find the first gh that's waiting for the glock | |
370 | * @gl: the glock | |
371 | */ | |
372 | ||
373 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) | |
374 | { | |
375 | struct gfs2_holder *gh; | |
376 | ||
377 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
378 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
379 | return gh; | |
380 | } | |
381 | return NULL; | |
382 | } | |
383 | ||
384 | /** | |
385 | * state_change - record that the glock is now in a different state | |
386 | * @gl: the glock | |
387 | * @new_state the new state | |
388 | * | |
389 | */ | |
390 | ||
391 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
392 | { | |
393 | int held1, held2; | |
394 | ||
395 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
396 | held2 = (new_state != LM_ST_UNLOCKED); | |
397 | ||
398 | if (held1 != held2) { | |
399 | if (held2) | |
400 | gfs2_glock_hold(gl); | |
401 | else | |
8ff22a6f | 402 | gfs2_glock_put_nolock(gl); |
6802e340 | 403 | } |
7b5e3d5f SW |
404 | if (held1 && held2 && list_empty(&gl->gl_holders)) |
405 | clear_bit(GLF_QUEUED, &gl->gl_flags); | |
6802e340 | 406 | |
7cf8dcd3 BP |
407 | if (new_state != gl->gl_target) |
408 | /* shorten our minimum hold time */ | |
409 | gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR, | |
410 | GL_GLOCK_MIN_HOLD); | |
6802e340 SW |
411 | gl->gl_state = new_state; |
412 | gl->gl_tchange = jiffies; | |
413 | } | |
414 | ||
415 | static void gfs2_demote_wake(struct gfs2_glock *gl) | |
416 | { | |
417 | gl->gl_demote_state = LM_ST_EXCLUSIVE; | |
418 | clear_bit(GLF_DEMOTE, &gl->gl_flags); | |
419 | smp_mb__after_clear_bit(); | |
420 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); | |
421 | } | |
422 | ||
423 | /** | |
424 | * finish_xmote - The DLM has replied to one of our lock requests | |
425 | * @gl: The glock | |
426 | * @ret: The status from the DLM | |
427 | * | |
428 | */ | |
429 | ||
430 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) | |
431 | { | |
432 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
433 | struct gfs2_holder *gh; | |
434 | unsigned state = ret & LM_OUT_ST_MASK; | |
813e0c46 | 435 | int rv; |
6802e340 SW |
436 | |
437 | spin_lock(&gl->gl_spin); | |
63997775 | 438 | trace_gfs2_glock_state_change(gl, state); |
6802e340 SW |
439 | state_change(gl, state); |
440 | gh = find_first_waiter(gl); | |
441 | ||
442 | /* Demote to UN request arrived during demote to SH or DF */ | |
443 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && | |
444 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) | |
445 | gl->gl_target = LM_ST_UNLOCKED; | |
446 | ||
447 | /* Check for state != intended state */ | |
448 | if (unlikely(state != gl->gl_target)) { | |
449 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { | |
450 | /* move to back of queue and try next entry */ | |
451 | if (ret & LM_OUT_CANCELED) { | |
452 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) | |
453 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
454 | gh = find_first_waiter(gl); | |
455 | gl->gl_target = gh->gh_state; | |
456 | goto retry; | |
457 | } | |
458 | /* Some error or failed "try lock" - report it */ | |
459 | if ((ret & LM_OUT_ERROR) || | |
460 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
461 | gl->gl_target = gl->gl_state; | |
462 | do_error(gl, ret); | |
463 | goto out; | |
464 | } | |
465 | } | |
466 | switch(state) { | |
467 | /* Unlocked due to conversion deadlock, try again */ | |
468 | case LM_ST_UNLOCKED: | |
469 | retry: | |
470 | do_xmote(gl, gh, gl->gl_target); | |
471 | break; | |
472 | /* Conversion fails, unlock and try again */ | |
473 | case LM_ST_SHARED: | |
474 | case LM_ST_DEFERRED: | |
475 | do_xmote(gl, gh, LM_ST_UNLOCKED); | |
476 | break; | |
477 | default: /* Everything else */ | |
478 | printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state); | |
479 | GLOCK_BUG_ON(gl, 1); | |
480 | } | |
481 | spin_unlock(&gl->gl_spin); | |
6802e340 SW |
482 | return; |
483 | } | |
484 | ||
485 | /* Fast path - we got what we asked for */ | |
486 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) | |
487 | gfs2_demote_wake(gl); | |
488 | if (state != LM_ST_UNLOCKED) { | |
489 | if (glops->go_xmote_bh) { | |
6802e340 SW |
490 | spin_unlock(&gl->gl_spin); |
491 | rv = glops->go_xmote_bh(gl, gh); | |
6802e340 SW |
492 | spin_lock(&gl->gl_spin); |
493 | if (rv) { | |
494 | do_error(gl, rv); | |
495 | goto out; | |
496 | } | |
497 | } | |
813e0c46 SW |
498 | rv = do_promote(gl); |
499 | if (rv == 2) | |
500 | goto out_locked; | |
6802e340 SW |
501 | } |
502 | out: | |
503 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
813e0c46 | 504 | out_locked: |
6802e340 | 505 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
506 | } |
507 | ||
6802e340 SW |
508 | /** |
509 | * do_xmote - Calls the DLM to change the state of a lock | |
510 | * @gl: The lock state | |
511 | * @gh: The holder (only for promotes) | |
512 | * @target: The target lock state | |
513 | * | |
514 | */ | |
515 | ||
516 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) | |
55ba474d HH |
517 | __releases(&gl->gl_spin) |
518 | __acquires(&gl->gl_spin) | |
6802e340 SW |
519 | { |
520 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
521 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
522 | unsigned int lck_flags = gh ? gh->gh_flags : 0; | |
523 | int ret; | |
524 | ||
525 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | | |
526 | LM_FLAG_PRIORITY); | |
921169ca SW |
527 | GLOCK_BUG_ON(gl, gl->gl_state == target); |
528 | GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target); | |
6802e340 SW |
529 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && |
530 | glops->go_inval) { | |
531 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
532 | do_error(gl, 0); /* Fail queued try locks */ | |
533 | } | |
47a25380 | 534 | gl->gl_req = target; |
a245769f SW |
535 | set_bit(GLF_BLOCKING, &gl->gl_flags); |
536 | if ((gl->gl_req == LM_ST_UNLOCKED) || | |
537 | (gl->gl_state == LM_ST_EXCLUSIVE) || | |
538 | (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB))) | |
539 | clear_bit(GLF_BLOCKING, &gl->gl_flags); | |
6802e340 | 540 | spin_unlock(&gl->gl_spin); |
06dfc306 BP |
541 | if (glops->go_sync) |
542 | glops->go_sync(gl); | |
6802e340 SW |
543 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
544 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); | |
545 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
546 | ||
547 | gfs2_glock_hold(gl); | |
921169ca SW |
548 | if (sdp->sd_lockstruct.ls_ops->lm_lock) { |
549 | /* lock_dlm */ | |
550 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags); | |
dba2d70c DT |
551 | if (ret) { |
552 | printk(KERN_ERR "GFS2: lm_lock ret %d\n", ret); | |
553 | GLOCK_BUG_ON(gl, 1); | |
554 | } | |
921169ca SW |
555 | } else { /* lock_nolock */ |
556 | finish_xmote(gl, target); | |
6802e340 SW |
557 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
558 | gfs2_glock_put(gl); | |
6802e340 | 559 | } |
921169ca | 560 | |
6802e340 SW |
561 | spin_lock(&gl->gl_spin); |
562 | } | |
563 | ||
564 | /** | |
565 | * find_first_holder - find the first "holder" gh | |
566 | * @gl: the glock | |
567 | */ | |
568 | ||
569 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) | |
570 | { | |
571 | struct gfs2_holder *gh; | |
572 | ||
573 | if (!list_empty(&gl->gl_holders)) { | |
574 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
575 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
576 | return gh; | |
577 | } | |
578 | return NULL; | |
579 | } | |
580 | ||
581 | /** | |
582 | * run_queue - do all outstanding tasks related to a glock | |
583 | * @gl: The glock in question | |
584 | * @nonblock: True if we must not block in run_queue | |
585 | * | |
586 | */ | |
587 | ||
588 | static void run_queue(struct gfs2_glock *gl, const int nonblock) | |
55ba474d HH |
589 | __releases(&gl->gl_spin) |
590 | __acquires(&gl->gl_spin) | |
6802e340 SW |
591 | { |
592 | struct gfs2_holder *gh = NULL; | |
813e0c46 | 593 | int ret; |
6802e340 SW |
594 | |
595 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
596 | return; | |
597 | ||
598 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); | |
599 | ||
600 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && | |
601 | gl->gl_demote_state != gl->gl_state) { | |
602 | if (find_first_holder(gl)) | |
d8348de0 | 603 | goto out_unlock; |
6802e340 SW |
604 | if (nonblock) |
605 | goto out_sched; | |
606 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); | |
265d529c | 607 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
6802e340 SW |
608 | gl->gl_target = gl->gl_demote_state; |
609 | } else { | |
610 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
611 | gfs2_demote_wake(gl); | |
813e0c46 SW |
612 | ret = do_promote(gl); |
613 | if (ret == 0) | |
d8348de0 | 614 | goto out_unlock; |
813e0c46 | 615 | if (ret == 2) |
a228df63 | 616 | goto out; |
6802e340 SW |
617 | gh = find_first_waiter(gl); |
618 | gl->gl_target = gh->gh_state; | |
619 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
620 | do_error(gl, 0); /* Fail queued try locks */ | |
621 | } | |
622 | do_xmote(gl, gh, gl->gl_target); | |
a228df63 | 623 | out: |
6802e340 SW |
624 | return; |
625 | ||
626 | out_sched: | |
7e71c55e SW |
627 | clear_bit(GLF_LOCK, &gl->gl_flags); |
628 | smp_mb__after_clear_bit(); | |
6802e340 SW |
629 | gfs2_glock_hold(gl); |
630 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
8ff22a6f | 631 | gfs2_glock_put_nolock(gl); |
7e71c55e SW |
632 | return; |
633 | ||
d8348de0 | 634 | out_unlock: |
6802e340 | 635 | clear_bit(GLF_LOCK, &gl->gl_flags); |
7e71c55e SW |
636 | smp_mb__after_clear_bit(); |
637 | return; | |
6802e340 SW |
638 | } |
639 | ||
b94a170e BM |
640 | static void delete_work_func(struct work_struct *work) |
641 | { | |
642 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete); | |
643 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
044b9414 | 644 | struct gfs2_inode *ip; |
b94a170e | 645 | struct inode *inode; |
044b9414 SW |
646 | u64 no_addr = gl->gl_name.ln_number; |
647 | ||
648 | ip = gl->gl_object; | |
649 | /* Note: Unsafe to dereference ip as we don't hold right refs/locks */ | |
b94a170e | 650 | |
b94a170e | 651 | if (ip) |
4667a0ec | 652 | inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1); |
044b9414 SW |
653 | else |
654 | inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED); | |
655 | if (inode && !IS_ERR(inode)) { | |
656 | d_prune_aliases(inode); | |
657 | iput(inode); | |
b94a170e BM |
658 | } |
659 | gfs2_glock_put(gl); | |
660 | } | |
661 | ||
c4f68a13 BM |
662 | static void glock_work_func(struct work_struct *work) |
663 | { | |
6802e340 | 664 | unsigned long delay = 0; |
c4f68a13 | 665 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
26bb7505 | 666 | int drop_ref = 0; |
c4f68a13 | 667 | |
26bb7505 | 668 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) { |
6802e340 | 669 | finish_xmote(gl, gl->gl_reply); |
26bb7505 SW |
670 | drop_ref = 1; |
671 | } | |
c4f68a13 | 672 | spin_lock(&gl->gl_spin); |
f90e5b5b | 673 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
265d529c SW |
674 | gl->gl_state != LM_ST_UNLOCKED && |
675 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { | |
6802e340 | 676 | unsigned long holdtime, now = jiffies; |
f90e5b5b | 677 | |
7cf8dcd3 | 678 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
6802e340 SW |
679 | if (time_before(now, holdtime)) |
680 | delay = holdtime - now; | |
f90e5b5b BP |
681 | |
682 | if (!delay) { | |
683 | clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags); | |
684 | set_bit(GLF_DEMOTE, &gl->gl_flags); | |
685 | } | |
6802e340 SW |
686 | } |
687 | run_queue(gl, 0); | |
c4f68a13 | 688 | spin_unlock(&gl->gl_spin); |
7cf8dcd3 | 689 | if (!delay) |
6802e340 | 690 | gfs2_glock_put(gl); |
7cf8dcd3 BP |
691 | else { |
692 | if (gl->gl_name.ln_type != LM_TYPE_INODE) | |
693 | delay = 0; | |
694 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
695 | gfs2_glock_put(gl); | |
696 | } | |
26bb7505 SW |
697 | if (drop_ref) |
698 | gfs2_glock_put(gl); | |
c4f68a13 BM |
699 | } |
700 | ||
b3b94faa DT |
701 | /** |
702 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
703 | * @sdp: The GFS2 superblock | |
704 | * @number: the lock number | |
705 | * @glops: The glock_operations to use | |
706 | * @create: If 0, don't create the glock if it doesn't exist | |
707 | * @glp: the glock is returned here | |
708 | * | |
709 | * This does not lock a glock, just finds/creates structures for one. | |
710 | * | |
711 | * Returns: errno | |
712 | */ | |
713 | ||
cd915493 | 714 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 | 715 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
716 | struct gfs2_glock **glp) |
717 | { | |
009d8518 | 718 | struct super_block *s = sdp->sd_vfs; |
37b2fa6a | 719 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
b3b94faa | 720 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 721 | unsigned int hash = gl_hash(sdp, &name); |
009d8518 | 722 | struct address_space *mapping; |
bc015cb8 | 723 | struct kmem_cache *cachep; |
b3b94faa | 724 | |
bc015cb8 | 725 | rcu_read_lock(); |
37b2fa6a | 726 | gl = search_bucket(hash, sdp, &name); |
bc015cb8 | 727 | rcu_read_unlock(); |
b3b94faa | 728 | |
64d576ba SW |
729 | *glp = gl; |
730 | if (gl) | |
b3b94faa | 731 | return 0; |
64d576ba SW |
732 | if (!create) |
733 | return -ENOENT; | |
b3b94faa | 734 | |
009d8518 | 735 | if (glops->go_flags & GLOF_ASPACE) |
bc015cb8 | 736 | cachep = gfs2_glock_aspace_cachep; |
009d8518 | 737 | else |
bc015cb8 SW |
738 | cachep = gfs2_glock_cachep; |
739 | gl = kmem_cache_alloc(cachep, GFP_KERNEL); | |
b3b94faa DT |
740 | if (!gl) |
741 | return -ENOMEM; | |
742 | ||
dba2d70c | 743 | memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); |
dba2d70c DT |
744 | |
745 | if (glops->go_flags & GLOF_LVB) { | |
4e2f8849 DT |
746 | gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_KERNEL); |
747 | if (!gl->gl_lksb.sb_lvbptr) { | |
dba2d70c DT |
748 | kmem_cache_free(cachep, gl); |
749 | return -ENOMEM; | |
750 | } | |
dba2d70c DT |
751 | } |
752 | ||
8f05228e | 753 | atomic_inc(&sdp->sd_glock_disposal); |
a245769f | 754 | gl->gl_sbd = sdp; |
ec45d9f5 | 755 | gl->gl_flags = 0; |
b3b94faa | 756 | gl->gl_name = name; |
16feb9fe | 757 | atomic_set(&gl->gl_ref, 1); |
b3b94faa | 758 | gl->gl_state = LM_ST_UNLOCKED; |
6802e340 | 759 | gl->gl_target = LM_ST_UNLOCKED; |
c4f68a13 | 760 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
37b2fa6a | 761 | gl->gl_hash = hash; |
b3b94faa | 762 | gl->gl_ops = glops; |
a245769f SW |
763 | gl->gl_dstamp = ktime_set(0, 0); |
764 | preempt_disable(); | |
765 | /* We use the global stats to estimate the initial per-glock stats */ | |
766 | gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type]; | |
767 | preempt_enable(); | |
768 | gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0; | |
769 | gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0; | |
c4f68a13 | 770 | gl->gl_tchange = jiffies; |
ec45d9f5 | 771 | gl->gl_object = NULL; |
7cf8dcd3 | 772 | gl->gl_hold_time = GL_GLOCK_DFT_HOLD; |
c4f68a13 | 773 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
b94a170e | 774 | INIT_WORK(&gl->gl_delete, delete_work_func); |
b3b94faa | 775 | |
009d8518 SW |
776 | mapping = gfs2_glock2aspace(gl); |
777 | if (mapping) { | |
778 | mapping->a_ops = &gfs2_meta_aops; | |
779 | mapping->host = s->s_bdev->bd_inode; | |
780 | mapping->flags = 0; | |
781 | mapping_set_gfp_mask(mapping, GFP_NOFS); | |
252aa6f5 | 782 | mapping->private_data = NULL; |
009d8518 SW |
783 | mapping->backing_dev_info = s->s_bdi; |
784 | mapping->writeback_index = 0; | |
b3b94faa DT |
785 | } |
786 | ||
bc015cb8 | 787 | spin_lock_bucket(hash); |
37b2fa6a | 788 | tmp = search_bucket(hash, sdp, &name); |
b3b94faa | 789 | if (tmp) { |
bc015cb8 | 790 | spin_unlock_bucket(hash); |
4e2f8849 | 791 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 792 | kmem_cache_free(cachep, gl); |
fc0e38da | 793 | atomic_dec(&sdp->sd_glock_disposal); |
b3b94faa DT |
794 | gl = tmp; |
795 | } else { | |
bc015cb8 SW |
796 | hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]); |
797 | spin_unlock_bucket(hash); | |
b3b94faa DT |
798 | } |
799 | ||
800 | *glp = gl; | |
801 | ||
802 | return 0; | |
b3b94faa DT |
803 | } |
804 | ||
805 | /** | |
806 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
807 | * @gl: the glock | |
808 | * @state: the state we're requesting | |
809 | * @flags: the modifier flags | |
810 | * @gh: the holder structure | |
811 | * | |
812 | */ | |
813 | ||
190562bd | 814 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
815 | struct gfs2_holder *gh) |
816 | { | |
817 | INIT_LIST_HEAD(&gh->gh_list); | |
818 | gh->gh_gl = gl; | |
d0dc80db | 819 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b1e058da | 820 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
821 | gh->gh_state = state; |
822 | gh->gh_flags = flags; | |
823 | gh->gh_error = 0; | |
824 | gh->gh_iflags = 0; | |
b3b94faa DT |
825 | gfs2_glock_hold(gl); |
826 | } | |
827 | ||
828 | /** | |
829 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
830 | * @state: the state we're requesting | |
831 | * @flags: the modifier flags | |
832 | * @gh: the holder structure | |
833 | * | |
834 | * Don't mess with the glock. | |
835 | * | |
836 | */ | |
837 | ||
190562bd | 838 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
839 | { |
840 | gh->gh_state = state; | |
579b78a4 | 841 | gh->gh_flags = flags; |
3b8249f6 | 842 | gh->gh_iflags = 0; |
d0dc80db | 843 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
1a0eae88 BP |
844 | if (gh->gh_owner_pid) |
845 | put_pid(gh->gh_owner_pid); | |
846 | gh->gh_owner_pid = get_pid(task_pid(current)); | |
b3b94faa DT |
847 | } |
848 | ||
849 | /** | |
850 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
851 | * @gh: the holder structure | |
852 | * | |
853 | */ | |
854 | ||
855 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
856 | { | |
b1e058da | 857 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
858 | gfs2_glock_put(gh->gh_gl); |
859 | gh->gh_gl = NULL; | |
d0dc80db | 860 | gh->gh_ip = 0; |
b3b94faa DT |
861 | } |
862 | ||
fe64d517 SW |
863 | /** |
864 | * gfs2_glock_holder_wait | |
865 | * @word: unused | |
866 | * | |
867 | * This function and gfs2_glock_demote_wait both show up in the WCHAN | |
868 | * field. Thus I've separated these otherwise identical functions in | |
869 | * order to be more informative to the user. | |
870 | */ | |
871 | ||
872 | static int gfs2_glock_holder_wait(void *word) | |
fee852e3 SW |
873 | { |
874 | schedule(); | |
875 | return 0; | |
876 | } | |
877 | ||
fe64d517 SW |
878 | static int gfs2_glock_demote_wait(void *word) |
879 | { | |
880 | schedule(); | |
881 | return 0; | |
882 | } | |
883 | ||
07a79049 BP |
884 | /** |
885 | * gfs2_glock_wait - wait on a glock acquisition | |
886 | * @gh: the glock holder | |
887 | * | |
888 | * Returns: 0 on success | |
889 | */ | |
890 | ||
891 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
da755fdb | 892 | { |
7cf8dcd3 BP |
893 | unsigned long time1 = jiffies; |
894 | ||
6802e340 | 895 | might_sleep(); |
fe64d517 | 896 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE); |
7cf8dcd3 BP |
897 | if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */ |
898 | /* Lengthen the minimum hold time. */ | |
899 | gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time + | |
900 | GL_GLOCK_HOLD_INCR, | |
901 | GL_GLOCK_MAX_HOLD); | |
07a79049 | 902 | return gh->gh_error; |
da755fdb SW |
903 | } |
904 | ||
b3b94faa | 905 | /** |
6802e340 SW |
906 | * handle_callback - process a demote request |
907 | * @gl: the glock | |
908 | * @state: the state the caller wants us to change to | |
b3b94faa | 909 | * |
6802e340 SW |
910 | * There are only two requests that we are going to see in actual |
911 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
912 | */ |
913 | ||
6802e340 | 914 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
81ffbf65 | 915 | unsigned long delay, bool remote) |
b3b94faa | 916 | { |
6802e340 | 917 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 918 | |
6802e340 SW |
919 | set_bit(bit, &gl->gl_flags); |
920 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
921 | gl->gl_demote_state = state; | |
922 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
923 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
924 | gl->gl_demote_state != state) { | |
925 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 926 | } |
b94a170e | 927 | if (gl->gl_ops->go_callback) |
81ffbf65 | 928 | gl->gl_ops->go_callback(gl, remote); |
7bd8b2eb | 929 | trace_gfs2_demote_rq(gl, remote); |
b3b94faa DT |
930 | } |
931 | ||
6802e340 | 932 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 | 933 | { |
5e69069c | 934 | struct va_format vaf; |
7c52b166 RP |
935 | va_list args; |
936 | ||
937 | va_start(args, fmt); | |
5e69069c | 938 | |
6802e340 | 939 | if (seq) { |
1bb49303 | 940 | seq_vprintf(seq, fmt, args); |
6802e340 | 941 | } else { |
5e69069c JP |
942 | vaf.fmt = fmt; |
943 | vaf.va = &args; | |
944 | ||
945 | printk(KERN_ERR " %pV", &vaf); | |
6802e340 | 946 | } |
5e69069c | 947 | |
7c52b166 RP |
948 | va_end(args); |
949 | } | |
950 | ||
b3b94faa DT |
951 | /** |
952 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
953 | * @gh: the holder structure to add | |
954 | * | |
6802e340 SW |
955 | * Eventually we should move the recursive locking trap to a |
956 | * debugging option or something like that. This is the fast | |
957 | * path and needs to have the minimum number of distractions. | |
958 | * | |
b3b94faa DT |
959 | */ |
960 | ||
6802e340 | 961 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
962 | __releases(&gl->gl_spin) |
963 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
964 | { |
965 | struct gfs2_glock *gl = gh->gh_gl; | |
6802e340 SW |
966 | struct gfs2_sbd *sdp = gl->gl_sbd; |
967 | struct list_head *insert_pt = NULL; | |
968 | struct gfs2_holder *gh2; | |
e5dc76b9 | 969 | int try_futile = 0; |
b3b94faa | 970 | |
b1e058da | 971 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
972 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
973 | BUG(); | |
190562bd | 974 | |
6802e340 SW |
975 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
976 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
e5dc76b9 | 977 | try_futile = !may_grant(gl, gh); |
6802e340 SW |
978 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
979 | goto fail; | |
980 | } | |
981 | ||
982 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
983 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
984 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
985 | goto trap_recursive; | |
e5dc76b9 BP |
986 | if (try_futile && |
987 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
6802e340 SW |
988 | fail: |
989 | gh->gh_error = GLR_TRYFAILED; | |
990 | gfs2_holder_wake(gh); | |
991 | return; | |
b4c20166 | 992 | } |
6802e340 SW |
993 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
994 | continue; | |
995 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
996 | insert_pt = &gh2->gh_list; | |
997 | } | |
7b5e3d5f | 998 | set_bit(GLF_QUEUED, &gl->gl_flags); |
edae38a6 | 999 | trace_gfs2_glock_queue(gh, 1); |
a245769f SW |
1000 | gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT); |
1001 | gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT); | |
6802e340 SW |
1002 | if (likely(insert_pt == NULL)) { |
1003 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
1004 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
1005 | goto do_cancel; | |
1006 | return; | |
1007 | } | |
1008 | list_add_tail(&gh->gh_list, insert_pt); | |
1009 | do_cancel: | |
1010 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
1011 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
1012 | spin_unlock(&gl->gl_spin); | |
048bca22 | 1013 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
f057f6cd | 1014 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
6802e340 | 1015 | spin_lock(&gl->gl_spin); |
b3b94faa | 1016 | } |
6802e340 | 1017 | return; |
b3b94faa | 1018 | |
6802e340 | 1019 | trap_recursive: |
7af584d3 | 1020 | printk(KERN_ERR "original: %pSR\n", (void *)gh2->gh_ip); |
6802e340 SW |
1021 | printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid)); |
1022 | printk(KERN_ERR "lock type: %d req lock state : %d\n", | |
1023 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); | |
7af584d3 | 1024 | printk(KERN_ERR "new: %pSR\n", (void *)gh->gh_ip); |
6802e340 SW |
1025 | printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid)); |
1026 | printk(KERN_ERR "lock type: %d req lock state : %d\n", | |
1027 | gh->gh_gl->gl_name.ln_type, gh->gh_state); | |
8eae1ca0 | 1028 | gfs2_dump_glock(NULL, gl); |
6802e340 | 1029 | BUG(); |
b3b94faa DT |
1030 | } |
1031 | ||
1032 | /** | |
1033 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1034 | * @gh: the holder structure | |
1035 | * | |
1036 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1037 | * | |
1038 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1039 | */ | |
1040 | ||
1041 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1042 | { | |
1043 | struct gfs2_glock *gl = gh->gh_gl; | |
1044 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1045 | int error = 0; | |
1046 | ||
6802e340 | 1047 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1048 | return -EIO; |
b3b94faa | 1049 | |
f42ab085 SW |
1050 | if (test_bit(GLF_LRU, &gl->gl_flags)) |
1051 | gfs2_glock_remove_from_lru(gl); | |
1052 | ||
b3b94faa DT |
1053 | spin_lock(&gl->gl_spin); |
1054 | add_to_queue(gh); | |
0809f6ec SW |
1055 | if ((LM_FLAG_NOEXP & gh->gh_flags) && |
1056 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
1057 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); | |
6802e340 | 1058 | run_queue(gl, 1); |
b3b94faa DT |
1059 | spin_unlock(&gl->gl_spin); |
1060 | ||
6802e340 SW |
1061 | if (!(gh->gh_flags & GL_ASYNC)) |
1062 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1063 | |
b3b94faa DT |
1064 | return error; |
1065 | } | |
1066 | ||
1067 | /** | |
1068 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1069 | * @gh: the holder | |
1070 | * | |
1071 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1072 | */ | |
1073 | ||
1074 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1075 | { | |
6802e340 | 1076 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1077 | } |
1078 | ||
1079 | /** | |
1080 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1081 | * @gh: the glock holder | |
1082 | * | |
1083 | */ | |
1084 | ||
1085 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1086 | { | |
1087 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1088 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1089 | unsigned delay = 0; |
6802e340 | 1090 | int fast_path = 0; |
b3b94faa | 1091 | |
6802e340 | 1092 | spin_lock(&gl->gl_spin); |
b3b94faa | 1093 | if (gh->gh_flags & GL_NOCACHE) |
81ffbf65 | 1094 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
b3b94faa | 1095 | |
b3b94faa | 1096 | list_del_init(&gh->gh_list); |
6802e340 | 1097 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1098 | if (glops->go_unlock) { |
6802e340 | 1099 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1100 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1101 | glops->go_unlock(gh); |
3042a2cc | 1102 | spin_lock(&gl->gl_spin); |
6802e340 | 1103 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1104 | } |
6802e340 SW |
1105 | if (list_empty(&gl->gl_holders) && |
1106 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1107 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1108 | fast_path = 1; | |
b3b94faa | 1109 | } |
4abb6ad9 BP |
1110 | if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl)) |
1111 | gfs2_glock_add_to_lru(gl); | |
1112 | ||
63997775 | 1113 | trace_gfs2_glock_queue(gh, 0); |
b3b94faa | 1114 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1115 | if (likely(fast_path)) |
1116 | return; | |
c4f68a13 BM |
1117 | |
1118 | gfs2_glock_hold(gl); | |
1119 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
7cf8dcd3 BP |
1120 | !test_bit(GLF_DEMOTE, &gl->gl_flags) && |
1121 | gl->gl_name.ln_type == LM_TYPE_INODE) | |
1122 | delay = gl->gl_hold_time; | |
c4f68a13 BM |
1123 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1124 | gfs2_glock_put(gl); | |
b3b94faa DT |
1125 | } |
1126 | ||
d93cfa98 AD |
1127 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1128 | { | |
1129 | struct gfs2_glock *gl = gh->gh_gl; | |
1130 | gfs2_glock_dq(gh); | |
81e1d450 BP |
1131 | might_sleep(); |
1132 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE); | |
d93cfa98 AD |
1133 | } |
1134 | ||
b3b94faa DT |
1135 | /** |
1136 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1137 | * @gh: the holder structure | |
1138 | * | |
1139 | */ | |
1140 | ||
1141 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1142 | { | |
1143 | gfs2_glock_dq(gh); | |
1144 | gfs2_holder_uninit(gh); | |
1145 | } | |
1146 | ||
1147 | /** | |
1148 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1149 | * @sdp: the filesystem | |
1150 | * @number: the lock number | |
1151 | * @glops: the glock operations for the type of glock | |
1152 | * @state: the state to acquire the glock in | |
25985edc | 1153 | * @flags: modifier flags for the acquisition |
b3b94faa DT |
1154 | * @gh: the struct gfs2_holder |
1155 | * | |
1156 | * Returns: errno | |
1157 | */ | |
1158 | ||
cd915493 | 1159 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1160 | const struct gfs2_glock_operations *glops, |
1161 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1162 | { |
1163 | struct gfs2_glock *gl; | |
1164 | int error; | |
1165 | ||
1166 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1167 | if (!error) { | |
1168 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1169 | gfs2_glock_put(gl); | |
1170 | } | |
1171 | ||
1172 | return error; | |
1173 | } | |
1174 | ||
1175 | /** | |
1176 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1177 | * @arg_a: the first structure | |
1178 | * @arg_b: the second structure | |
1179 | * | |
1180 | */ | |
1181 | ||
1182 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1183 | { | |
a5e08a9e SW |
1184 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1185 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1186 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1187 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1188 | |
1189 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1190 | return 1; |
1191 | if (a->ln_number < b->ln_number) | |
1192 | return -1; | |
1c0f4872 | 1193 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1194 | return 0; |
b3b94faa DT |
1195 | } |
1196 | ||
1197 | /** | |
1198 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1199 | * @num_gh: the number of structures | |
1200 | * @ghs: an array of struct gfs2_holder structures | |
1201 | * | |
1202 | * Returns: 0 on success (all glocks acquired), | |
1203 | * errno on failure (no glocks acquired) | |
1204 | */ | |
1205 | ||
1206 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1207 | struct gfs2_holder **p) | |
1208 | { | |
1209 | unsigned int x; | |
1210 | int error = 0; | |
1211 | ||
1212 | for (x = 0; x < num_gh; x++) | |
1213 | p[x] = &ghs[x]; | |
1214 | ||
1215 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1216 | ||
1217 | for (x = 0; x < num_gh; x++) { | |
1218 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1219 | ||
1220 | error = gfs2_glock_nq(p[x]); | |
1221 | if (error) { | |
1222 | while (x--) | |
1223 | gfs2_glock_dq(p[x]); | |
1224 | break; | |
1225 | } | |
1226 | } | |
1227 | ||
1228 | return error; | |
1229 | } | |
1230 | ||
1231 | /** | |
1232 | * gfs2_glock_nq_m - acquire multiple glocks | |
1233 | * @num_gh: the number of structures | |
1234 | * @ghs: an array of struct gfs2_holder structures | |
1235 | * | |
b3b94faa DT |
1236 | * |
1237 | * Returns: 0 on success (all glocks acquired), | |
1238 | * errno on failure (no glocks acquired) | |
1239 | */ | |
1240 | ||
1241 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1242 | { | |
eaf5bd3c SW |
1243 | struct gfs2_holder *tmp[4]; |
1244 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1245 | int error = 0; |
1246 | ||
eaf5bd3c SW |
1247 | switch(num_gh) { |
1248 | case 0: | |
b3b94faa | 1249 | return 0; |
eaf5bd3c | 1250 | case 1: |
b3b94faa DT |
1251 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1252 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1253 | default: |
1254 | if (num_gh <= 4) | |
b3b94faa | 1255 | break; |
eaf5bd3c SW |
1256 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1257 | if (!pph) | |
1258 | return -ENOMEM; | |
b3b94faa DT |
1259 | } |
1260 | ||
eaf5bd3c | 1261 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1262 | |
eaf5bd3c SW |
1263 | if (pph != tmp) |
1264 | kfree(pph); | |
b3b94faa DT |
1265 | |
1266 | return error; | |
1267 | } | |
1268 | ||
1269 | /** | |
1270 | * gfs2_glock_dq_m - release multiple glocks | |
1271 | * @num_gh: the number of structures | |
1272 | * @ghs: an array of struct gfs2_holder structures | |
1273 | * | |
1274 | */ | |
1275 | ||
1276 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1277 | { | |
fa1bbdea BP |
1278 | while (num_gh--) |
1279 | gfs2_glock_dq(&ghs[num_gh]); | |
b3b94faa DT |
1280 | } |
1281 | ||
f057f6cd | 1282 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
da755fdb | 1283 | { |
c4f68a13 BM |
1284 | unsigned long delay = 0; |
1285 | unsigned long holdtime; | |
1286 | unsigned long now = jiffies; | |
b3b94faa | 1287 | |
f057f6cd | 1288 | gfs2_glock_hold(gl); |
7cf8dcd3 BP |
1289 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
1290 | if (test_bit(GLF_QUEUED, &gl->gl_flags) && | |
1291 | gl->gl_name.ln_type == LM_TYPE_INODE) { | |
7b5e3d5f SW |
1292 | if (time_before(now, holdtime)) |
1293 | delay = holdtime - now; | |
1294 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) | |
7cf8dcd3 | 1295 | delay = gl->gl_hold_time; |
7b5e3d5f | 1296 | } |
b3b94faa | 1297 | |
6802e340 | 1298 | spin_lock(&gl->gl_spin); |
81ffbf65 | 1299 | handle_callback(gl, state, delay, true); |
6802e340 | 1300 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1301 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1302 | gfs2_glock_put(gl); | |
b3b94faa DT |
1303 | } |
1304 | ||
0809f6ec SW |
1305 | /** |
1306 | * gfs2_should_freeze - Figure out if glock should be frozen | |
1307 | * @gl: The glock in question | |
1308 | * | |
1309 | * Glocks are not frozen if (a) the result of the dlm operation is | |
1310 | * an error, (b) the locking operation was an unlock operation or | |
1311 | * (c) if there is a "noexp" flagged request anywhere in the queue | |
1312 | * | |
1313 | * Returns: 1 if freezing should occur, 0 otherwise | |
1314 | */ | |
1315 | ||
1316 | static int gfs2_should_freeze(const struct gfs2_glock *gl) | |
1317 | { | |
1318 | const struct gfs2_holder *gh; | |
1319 | ||
1320 | if (gl->gl_reply & ~LM_OUT_ST_MASK) | |
1321 | return 0; | |
1322 | if (gl->gl_target == LM_ST_UNLOCKED) | |
1323 | return 0; | |
1324 | ||
1325 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
1326 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1327 | continue; | |
1328 | if (LM_FLAG_NOEXP & gh->gh_flags) | |
1329 | return 0; | |
1330 | } | |
1331 | ||
1332 | return 1; | |
1333 | } | |
1334 | ||
b3b94faa | 1335 | /** |
f057f6cd SW |
1336 | * gfs2_glock_complete - Callback used by locking |
1337 | * @gl: Pointer to the glock | |
1338 | * @ret: The return value from the dlm | |
b3b94faa | 1339 | * |
47a25380 SW |
1340 | * The gl_reply field is under the gl_spin lock so that it is ok |
1341 | * to use a bitfield shared with other glock state fields. | |
b3b94faa DT |
1342 | */ |
1343 | ||
f057f6cd | 1344 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
b3b94faa | 1345 | { |
f057f6cd | 1346 | struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; |
0809f6ec | 1347 | |
47a25380 | 1348 | spin_lock(&gl->gl_spin); |
f057f6cd | 1349 | gl->gl_reply = ret; |
0809f6ec | 1350 | |
e0c2a9aa | 1351 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) { |
0809f6ec | 1352 | if (gfs2_should_freeze(gl)) { |
f057f6cd | 1353 | set_bit(GLF_FROZEN, &gl->gl_flags); |
0809f6ec | 1354 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1355 | return; |
0809f6ec | 1356 | } |
b3b94faa | 1357 | } |
47a25380 SW |
1358 | |
1359 | spin_unlock(&gl->gl_spin); | |
f057f6cd | 1360 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
47a25380 | 1361 | smp_wmb(); |
f057f6cd SW |
1362 | gfs2_glock_hold(gl); |
1363 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1364 | gfs2_glock_put(gl); | |
b3b94faa DT |
1365 | } |
1366 | ||
4506a519 SW |
1367 | static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) |
1368 | { | |
1369 | struct gfs2_glock *gla, *glb; | |
1370 | ||
1371 | gla = list_entry(a, struct gfs2_glock, gl_lru); | |
1372 | glb = list_entry(b, struct gfs2_glock, gl_lru); | |
1373 | ||
1374 | if (gla->gl_name.ln_number > glb->gl_name.ln_number) | |
1375 | return 1; | |
1376 | if (gla->gl_name.ln_number < glb->gl_name.ln_number) | |
1377 | return -1; | |
1378 | ||
1379 | return 0; | |
1380 | } | |
1381 | ||
1382 | /** | |
1383 | * gfs2_dispose_glock_lru - Demote a list of glocks | |
1384 | * @list: The list to dispose of | |
1385 | * | |
1386 | * Disposing of glocks may involve disk accesses, so that here we sort | |
1387 | * the glocks by number (i.e. disk location of the inodes) so that if | |
1388 | * there are any such accesses, they'll be sent in order (mostly). | |
1389 | * | |
1390 | * Must be called under the lru_lock, but may drop and retake this | |
1391 | * lock. While the lru_lock is dropped, entries may vanish from the | |
1392 | * list, but no new entries will appear on the list (since it is | |
1393 | * private) | |
1394 | */ | |
1395 | ||
1396 | static void gfs2_dispose_glock_lru(struct list_head *list) | |
1397 | __releases(&lru_lock) | |
1398 | __acquires(&lru_lock) | |
1399 | { | |
1400 | struct gfs2_glock *gl; | |
1401 | ||
1402 | list_sort(NULL, list, glock_cmp); | |
1403 | ||
1404 | while(!list_empty(list)) { | |
1405 | gl = list_entry(list->next, struct gfs2_glock, gl_lru); | |
1406 | list_del_init(&gl->gl_lru); | |
1407 | clear_bit(GLF_LRU, &gl->gl_flags); | |
1408 | gfs2_glock_hold(gl); | |
1409 | spin_unlock(&lru_lock); | |
1410 | spin_lock(&gl->gl_spin); | |
1411 | if (demote_ok(gl)) | |
81ffbf65 | 1412 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
4506a519 SW |
1413 | WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); |
1414 | smp_mb__after_clear_bit(); | |
1415 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1416 | gfs2_glock_put_nolock(gl); | |
1417 | spin_unlock(&gl->gl_spin); | |
1418 | spin_lock(&lru_lock); | |
1419 | } | |
1420 | } | |
1421 | ||
2a005855 SW |
1422 | /** |
1423 | * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote | |
1424 | * @nr: The number of entries to scan | |
1425 | * | |
4506a519 SW |
1426 | * This function selects the entries on the LRU which are able to |
1427 | * be demoted, and then kicks off the process by calling | |
1428 | * gfs2_dispose_glock_lru() above. | |
2a005855 | 1429 | */ |
b3b94faa | 1430 | |
2a005855 | 1431 | static void gfs2_scan_glock_lru(int nr) |
b3b94faa DT |
1432 | { |
1433 | struct gfs2_glock *gl; | |
97cc1025 | 1434 | LIST_HEAD(skipped); |
4506a519 | 1435 | LIST_HEAD(dispose); |
b3b94faa | 1436 | |
97cc1025 SW |
1437 | spin_lock(&lru_lock); |
1438 | while(nr && !list_empty(&lru_list)) { | |
1439 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); | |
97cc1025 SW |
1440 | |
1441 | /* Test for being demotable */ | |
1442 | if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { | |
4506a519 SW |
1443 | list_move(&gl->gl_lru, &dispose); |
1444 | atomic_dec(&lru_count); | |
1445 | nr--; | |
2163b1e6 | 1446 | continue; |
97cc1025 | 1447 | } |
4506a519 SW |
1448 | |
1449 | list_move(&gl->gl_lru, &skipped); | |
b3b94faa | 1450 | } |
97cc1025 | 1451 | list_splice(&skipped, &lru_list); |
4506a519 SW |
1452 | if (!list_empty(&dispose)) |
1453 | gfs2_dispose_glock_lru(&dispose); | |
97cc1025 | 1454 | spin_unlock(&lru_lock); |
2a005855 SW |
1455 | } |
1456 | ||
1457 | static int gfs2_shrink_glock_memory(struct shrinker *shrink, | |
1458 | struct shrink_control *sc) | |
1459 | { | |
1460 | if (sc->nr_to_scan) { | |
1461 | if (!(sc->gfp_mask & __GFP_FS)) | |
1462 | return -1; | |
1463 | gfs2_scan_glock_lru(sc->nr_to_scan); | |
1464 | } | |
1465 | ||
97cc1025 | 1466 | return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure; |
b3b94faa DT |
1467 | } |
1468 | ||
97cc1025 SW |
1469 | static struct shrinker glock_shrinker = { |
1470 | .shrink = gfs2_shrink_glock_memory, | |
1471 | .seeks = DEFAULT_SEEKS, | |
1472 | }; | |
1473 | ||
b3b94faa DT |
1474 | /** |
1475 | * examine_bucket - Call a function for glock in a hash bucket | |
1476 | * @examiner: the function | |
1477 | * @sdp: the filesystem | |
1478 | * @bucket: the bucket | |
1479 | * | |
b3b94faa DT |
1480 | */ |
1481 | ||
bc015cb8 | 1482 | static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, |
37b2fa6a | 1483 | unsigned int hash) |
b3b94faa | 1484 | { |
bc015cb8 SW |
1485 | struct gfs2_glock *gl; |
1486 | struct hlist_bl_head *head = &gl_hash_table[hash]; | |
1487 | struct hlist_bl_node *pos; | |
b3b94faa | 1488 | |
bc015cb8 SW |
1489 | rcu_read_lock(); |
1490 | hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { | |
1491 | if ((gl->gl_sbd == sdp) && atomic_read(&gl->gl_ref)) | |
24264434 | 1492 | examiner(gl); |
b3b94faa | 1493 | } |
bc015cb8 | 1494 | rcu_read_unlock(); |
8fbbfd21 | 1495 | cond_resched(); |
bc015cb8 SW |
1496 | } |
1497 | ||
1498 | static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp) | |
1499 | { | |
1500 | unsigned x; | |
1501 | ||
1502 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
1503 | examine_bucket(examiner, sdp, x); | |
b3b94faa DT |
1504 | } |
1505 | ||
f057f6cd SW |
1506 | |
1507 | /** | |
1508 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting | |
1509 | * @gl: The glock to thaw | |
1510 | * | |
1511 | * N.B. When we freeze a glock, we leave a ref to the glock outstanding, | |
1512 | * so this has to result in the ref count being dropped by one. | |
1513 | */ | |
1514 | ||
1515 | static void thaw_glock(struct gfs2_glock *gl) | |
1516 | { | |
1517 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
1518 | return; | |
f057f6cd SW |
1519 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
1520 | gfs2_glock_hold(gl); | |
1521 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1522 | gfs2_glock_put(gl); | |
f057f6cd SW |
1523 | } |
1524 | ||
b3b94faa DT |
1525 | /** |
1526 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1527 | * @gl: the glock to look at | |
1528 | * | |
1529 | */ | |
1530 | ||
1531 | static void clear_glock(struct gfs2_glock *gl) | |
1532 | { | |
f42ab085 | 1533 | gfs2_glock_remove_from_lru(gl); |
b3b94faa | 1534 | |
6802e340 | 1535 | spin_lock(&gl->gl_spin); |
c741c455 | 1536 | if (gl->gl_state != LM_ST_UNLOCKED) |
81ffbf65 | 1537 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
6802e340 SW |
1538 | spin_unlock(&gl->gl_spin); |
1539 | gfs2_glock_hold(gl); | |
1540 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1541 | gfs2_glock_put(gl); | |
b3b94faa DT |
1542 | } |
1543 | ||
f057f6cd SW |
1544 | /** |
1545 | * gfs2_glock_thaw - Thaw any frozen glocks | |
1546 | * @sdp: The super block | |
1547 | * | |
1548 | */ | |
1549 | ||
1550 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) | |
1551 | { | |
bc015cb8 SW |
1552 | glock_hash_walk(thaw_glock, sdp); |
1553 | } | |
f057f6cd | 1554 | |
bc015cb8 SW |
1555 | static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
1556 | { | |
1557 | int ret; | |
1558 | spin_lock(&gl->gl_spin); | |
8eae1ca0 | 1559 | ret = gfs2_dump_glock(seq, gl); |
bc015cb8 SW |
1560 | spin_unlock(&gl->gl_spin); |
1561 | return ret; | |
1562 | } | |
1563 | ||
1564 | static void dump_glock_func(struct gfs2_glock *gl) | |
1565 | { | |
1566 | dump_glock(NULL, gl); | |
f057f6cd SW |
1567 | } |
1568 | ||
b3b94faa DT |
1569 | /** |
1570 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1571 | * @sdp: the filesystem | |
1572 | * @wait: wait until it's all gone | |
1573 | * | |
1bdad606 | 1574 | * Called when unmounting the filesystem. |
b3b94faa DT |
1575 | */ |
1576 | ||
fefc03bf | 1577 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa | 1578 | { |
fb6791d1 | 1579 | set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags); |
222cb538 | 1580 | flush_workqueue(glock_workqueue); |
bc015cb8 | 1581 | glock_hash_walk(clear_glock, sdp); |
8f05228e SW |
1582 | flush_workqueue(glock_workqueue); |
1583 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); | |
bc015cb8 | 1584 | glock_hash_walk(dump_glock_func, sdp); |
b3b94faa DT |
1585 | } |
1586 | ||
813e0c46 SW |
1587 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1588 | { | |
1589 | struct gfs2_glock *gl = ip->i_gl; | |
1590 | int ret; | |
1591 | ||
1592 | ret = gfs2_truncatei_resume(ip); | |
1593 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); | |
1594 | ||
1595 | spin_lock(&gl->gl_spin); | |
1596 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1597 | run_queue(gl, 1); | |
1598 | spin_unlock(&gl->gl_spin); | |
1599 | } | |
1600 | ||
6802e340 | 1601 | static const char *state2str(unsigned state) |
04b933f2 | 1602 | { |
6802e340 SW |
1603 | switch(state) { |
1604 | case LM_ST_UNLOCKED: | |
1605 | return "UN"; | |
1606 | case LM_ST_SHARED: | |
1607 | return "SH"; | |
1608 | case LM_ST_DEFERRED: | |
1609 | return "DF"; | |
1610 | case LM_ST_EXCLUSIVE: | |
1611 | return "EX"; | |
1612 | } | |
1613 | return "??"; | |
1614 | } | |
1615 | ||
1616 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1617 | { | |
1618 | char *p = buf; | |
1619 | if (flags & LM_FLAG_TRY) | |
1620 | *p++ = 't'; | |
1621 | if (flags & LM_FLAG_TRY_1CB) | |
1622 | *p++ = 'T'; | |
1623 | if (flags & LM_FLAG_NOEXP) | |
1624 | *p++ = 'e'; | |
1625 | if (flags & LM_FLAG_ANY) | |
f057f6cd | 1626 | *p++ = 'A'; |
6802e340 SW |
1627 | if (flags & LM_FLAG_PRIORITY) |
1628 | *p++ = 'p'; | |
1629 | if (flags & GL_ASYNC) | |
1630 | *p++ = 'a'; | |
1631 | if (flags & GL_EXACT) | |
1632 | *p++ = 'E'; | |
6802e340 SW |
1633 | if (flags & GL_NOCACHE) |
1634 | *p++ = 'c'; | |
1635 | if (test_bit(HIF_HOLDER, &iflags)) | |
1636 | *p++ = 'H'; | |
1637 | if (test_bit(HIF_WAIT, &iflags)) | |
1638 | *p++ = 'W'; | |
1639 | if (test_bit(HIF_FIRST, &iflags)) | |
1640 | *p++ = 'F'; | |
1641 | *p = 0; | |
1642 | return buf; | |
04b933f2 RP |
1643 | } |
1644 | ||
b3b94faa DT |
1645 | /** |
1646 | * dump_holder - print information about a glock holder | |
6802e340 | 1647 | * @seq: the seq_file struct |
b3b94faa DT |
1648 | * @gh: the glock holder |
1649 | * | |
1650 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1651 | */ | |
1652 | ||
6802e340 | 1653 | static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1654 | { |
6802e340 | 1655 | struct task_struct *gh_owner = NULL; |
6802e340 | 1656 | char flags_buf[32]; |
b3b94faa | 1657 | |
6802e340 | 1658 | if (gh->gh_owner_pid) |
b1e058da | 1659 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
cc18152e JP |
1660 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
1661 | state2str(gh->gh_state), | |
1662 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1663 | gh->gh_error, | |
1664 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1665 | gh_owner ? gh_owner->comm : "(ended)", | |
1666 | (void *)gh->gh_ip); | |
7c52b166 | 1667 | return 0; |
b3b94faa DT |
1668 | } |
1669 | ||
627c10b7 | 1670 | static const char *gflags2str(char *buf, const struct gfs2_glock *gl) |
6802e340 | 1671 | { |
627c10b7 | 1672 | const unsigned long *gflags = &gl->gl_flags; |
6802e340 | 1673 | char *p = buf; |
627c10b7 | 1674 | |
6802e340 SW |
1675 | if (test_bit(GLF_LOCK, gflags)) |
1676 | *p++ = 'l'; | |
6802e340 SW |
1677 | if (test_bit(GLF_DEMOTE, gflags)) |
1678 | *p++ = 'D'; | |
1679 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1680 | *p++ = 'd'; | |
1681 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1682 | *p++ = 'p'; | |
1683 | if (test_bit(GLF_DIRTY, gflags)) | |
1684 | *p++ = 'y'; | |
1685 | if (test_bit(GLF_LFLUSH, gflags)) | |
1686 | *p++ = 'f'; | |
1687 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1688 | *p++ = 'i'; | |
1689 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1690 | *p++ = 'r'; | |
f057f6cd | 1691 | if (test_bit(GLF_INITIAL, gflags)) |
d8348de0 | 1692 | *p++ = 'I'; |
f057f6cd SW |
1693 | if (test_bit(GLF_FROZEN, gflags)) |
1694 | *p++ = 'F'; | |
7b5e3d5f SW |
1695 | if (test_bit(GLF_QUEUED, gflags)) |
1696 | *p++ = 'q'; | |
627c10b7 SW |
1697 | if (test_bit(GLF_LRU, gflags)) |
1698 | *p++ = 'L'; | |
1699 | if (gl->gl_object) | |
1700 | *p++ = 'o'; | |
a245769f SW |
1701 | if (test_bit(GLF_BLOCKING, gflags)) |
1702 | *p++ = 'b'; | |
6802e340 SW |
1703 | *p = 0; |
1704 | return buf; | |
b3b94faa DT |
1705 | } |
1706 | ||
1707 | /** | |
8eae1ca0 | 1708 | * gfs2_dump_glock - print information about a glock |
6802e340 | 1709 | * @seq: The seq_file struct |
b3b94faa | 1710 | * @gl: the glock |
6802e340 SW |
1711 | * |
1712 | * The file format is as follows: | |
1713 | * One line per object, capital letters are used to indicate objects | |
1714 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1715 | * other objects are indented by a single space and follow the glock to | |
1716 | * which they are related. Fields are indicated by lower case letters | |
1717 | * followed by a colon and the field value, except for strings which are in | |
1718 | * [] so that its possible to see if they are composed of spaces for | |
1719 | * example. The field's are n = number (id of the object), f = flags, | |
1720 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa DT |
1721 | * |
1722 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1723 | */ | |
1724 | ||
8eae1ca0 | 1725 | int gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1726 | { |
6802e340 SW |
1727 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1728 | unsigned long long dtime; | |
1729 | const struct gfs2_holder *gh; | |
1730 | char gflags_buf[32]; | |
1731 | int error = 0; | |
b3b94faa | 1732 | |
6802e340 SW |
1733 | dtime = jiffies - gl->gl_demote_time; |
1734 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1735 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1736 | dtime = 0; | |
7cf8dcd3 | 1737 | 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 |
1738 | state2str(gl->gl_state), |
1739 | gl->gl_name.ln_type, | |
1740 | (unsigned long long)gl->gl_name.ln_number, | |
627c10b7 | 1741 | gflags2str(gflags_buf, gl), |
6802e340 SW |
1742 | state2str(gl->gl_target), |
1743 | state2str(gl->gl_demote_state), dtime, | |
6802e340 | 1744 | atomic_read(&gl->gl_ail_count), |
f42ab085 | 1745 | atomic_read(&gl->gl_revokes), |
7cf8dcd3 | 1746 | atomic_read(&gl->gl_ref), gl->gl_hold_time); |
b3b94faa | 1747 | |
b3b94faa | 1748 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
6802e340 | 1749 | error = dump_holder(seq, gh); |
b3b94faa DT |
1750 | if (error) |
1751 | goto out; | |
1752 | } | |
6802e340 SW |
1753 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
1754 | error = glops->go_dump(seq, gl); | |
a91ea69f | 1755 | out: |
b3b94faa DT |
1756 | return error; |
1757 | } | |
1758 | ||
a245769f SW |
1759 | static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr) |
1760 | { | |
1761 | struct gfs2_glock *gl = iter_ptr; | |
1762 | ||
1763 | seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n", | |
1764 | gl->gl_name.ln_type, | |
1765 | (unsigned long long)gl->gl_name.ln_number, | |
1766 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTT], | |
1767 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR], | |
1768 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB], | |
1769 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB], | |
1770 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRT], | |
1771 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR], | |
1772 | (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT], | |
1773 | (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]); | |
1774 | return 0; | |
1775 | } | |
1776 | ||
1777 | static const char *gfs2_gltype[] = { | |
1778 | "type", | |
1779 | "reserved", | |
1780 | "nondisk", | |
1781 | "inode", | |
1782 | "rgrp", | |
1783 | "meta", | |
1784 | "iopen", | |
1785 | "flock", | |
1786 | "plock", | |
1787 | "quota", | |
1788 | "journal", | |
1789 | }; | |
1790 | ||
1791 | static const char *gfs2_stype[] = { | |
1792 | [GFS2_LKS_SRTT] = "srtt", | |
1793 | [GFS2_LKS_SRTTVAR] = "srttvar", | |
1794 | [GFS2_LKS_SRTTB] = "srttb", | |
1795 | [GFS2_LKS_SRTTVARB] = "srttvarb", | |
1796 | [GFS2_LKS_SIRT] = "sirt", | |
1797 | [GFS2_LKS_SIRTVAR] = "sirtvar", | |
1798 | [GFS2_LKS_DCOUNT] = "dlm", | |
1799 | [GFS2_LKS_QCOUNT] = "queue", | |
1800 | }; | |
1801 | ||
1802 | #define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype)) | |
1803 | ||
1804 | static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr) | |
1805 | { | |
1806 | struct gfs2_glock_iter *gi = seq->private; | |
1807 | struct gfs2_sbd *sdp = gi->sdp; | |
1808 | unsigned index = gi->hash >> 3; | |
1809 | unsigned subindex = gi->hash & 0x07; | |
1810 | s64 value; | |
1811 | int i; | |
1812 | ||
1813 | if (index == 0 && subindex != 0) | |
1814 | return 0; | |
6802e340 | 1815 | |
a245769f SW |
1816 | seq_printf(seq, "%-10s %8s:", gfs2_gltype[index], |
1817 | (index == 0) ? "cpu": gfs2_stype[subindex]); | |
b3b94faa | 1818 | |
a245769f SW |
1819 | for_each_possible_cpu(i) { |
1820 | const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i); | |
1821 | if (index == 0) { | |
1822 | value = i; | |
1823 | } else { | |
1824 | value = lkstats->lkstats[index - 1].stats[subindex]; | |
1825 | } | |
1826 | seq_printf(seq, " %15lld", (long long)value); | |
1827 | } | |
1828 | seq_putc(seq, '\n'); | |
1829 | return 0; | |
1830 | } | |
8fbbfd21 | 1831 | |
85d1da67 SW |
1832 | int __init gfs2_glock_init(void) |
1833 | { | |
1834 | unsigned i; | |
1835 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
bc015cb8 | 1836 | INIT_HLIST_BL_HEAD(&gl_hash_table[i]); |
087efdd3 | 1837 | } |
8fbbfd21 | 1838 | |
d2115778 | 1839 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
58a69cb4 | 1840 | WQ_HIGHPRI | WQ_FREEZABLE, 0); |
97cc1025 | 1841 | if (IS_ERR(glock_workqueue)) |
c4f68a13 | 1842 | return PTR_ERR(glock_workqueue); |
d2115778 | 1843 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
58a69cb4 | 1844 | WQ_MEM_RECLAIM | WQ_FREEZABLE, |
d2115778 | 1845 | 0); |
b94a170e BM |
1846 | if (IS_ERR(gfs2_delete_workqueue)) { |
1847 | destroy_workqueue(glock_workqueue); | |
1848 | return PTR_ERR(gfs2_delete_workqueue); | |
1849 | } | |
97cc1025 SW |
1850 | |
1851 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1852 | |
85d1da67 SW |
1853 | return 0; |
1854 | } | |
1855 | ||
8fbbfd21 SW |
1856 | void gfs2_glock_exit(void) |
1857 | { | |
97cc1025 | 1858 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1859 | destroy_workqueue(glock_workqueue); |
b94a170e | 1860 | destroy_workqueue(gfs2_delete_workqueue); |
8fbbfd21 SW |
1861 | } |
1862 | ||
bc015cb8 SW |
1863 | static inline struct gfs2_glock *glock_hash_chain(unsigned hash) |
1864 | { | |
1865 | return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]), | |
1866 | struct gfs2_glock, gl_list); | |
1867 | } | |
1868 | ||
1869 | static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl) | |
1870 | { | |
7e32d026 | 1871 | return hlist_bl_entry(rcu_dereference(gl->gl_list.next), |
bc015cb8 SW |
1872 | struct gfs2_glock, gl_list); |
1873 | } | |
1874 | ||
6802e340 | 1875 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1876 | { |
7b08fc62 SW |
1877 | struct gfs2_glock *gl; |
1878 | ||
bc015cb8 SW |
1879 | do { |
1880 | gl = gi->gl; | |
1881 | if (gl) { | |
1882 | gi->gl = glock_hash_next(gl); | |
ba1ddcb6 | 1883 | gi->nhash++; |
bc015cb8 | 1884 | } else { |
ba1ddcb6 SW |
1885 | if (gi->hash >= GFS2_GL_HASH_SIZE) { |
1886 | rcu_read_unlock(); | |
1887 | return 1; | |
1888 | } | |
bc015cb8 | 1889 | gi->gl = glock_hash_chain(gi->hash); |
ba1ddcb6 | 1890 | gi->nhash = 0; |
bc015cb8 SW |
1891 | } |
1892 | while (gi->gl == NULL) { | |
1893 | gi->hash++; | |
1894 | if (gi->hash >= GFS2_GL_HASH_SIZE) { | |
1895 | rcu_read_unlock(); | |
1896 | return 1; | |
1897 | } | |
1898 | gi->gl = glock_hash_chain(gi->hash); | |
ba1ddcb6 | 1899 | gi->nhash = 0; |
bc015cb8 SW |
1900 | } |
1901 | /* Skip entries for other sb and dead entries */ | |
1902 | } while (gi->sdp != gi->gl->gl_sbd || atomic_read(&gi->gl->gl_ref) == 0); | |
a947e033 | 1903 | |
7c52b166 RP |
1904 | return 0; |
1905 | } | |
1906 | ||
6802e340 | 1907 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1908 | { |
6802e340 | 1909 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1910 | loff_t n = *pos; |
1911 | ||
ba1ddcb6 SW |
1912 | if (gi->last_pos <= *pos) |
1913 | n = gi->nhash + (*pos - gi->last_pos); | |
1914 | else | |
1915 | gi->hash = 0; | |
1916 | ||
1917 | gi->nhash = 0; | |
bc015cb8 | 1918 | rcu_read_lock(); |
7c52b166 | 1919 | |
6802e340 | 1920 | do { |
bc015cb8 | 1921 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1922 | return NULL; |
6802e340 | 1923 | } while (n--); |
7c52b166 | 1924 | |
ba1ddcb6 | 1925 | gi->last_pos = *pos; |
6802e340 | 1926 | return gi->gl; |
7c52b166 RP |
1927 | } |
1928 | ||
6802e340 | 1929 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1930 | loff_t *pos) |
1931 | { | |
6802e340 | 1932 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1933 | |
1934 | (*pos)++; | |
ba1ddcb6 | 1935 | gi->last_pos = *pos; |
bc015cb8 | 1936 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1937 | return NULL; |
7c52b166 | 1938 | |
6802e340 | 1939 | return gi->gl; |
7c52b166 RP |
1940 | } |
1941 | ||
6802e340 | 1942 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1943 | { |
6802e340 | 1944 | struct gfs2_glock_iter *gi = seq->private; |
bc015cb8 SW |
1945 | |
1946 | if (gi->gl) | |
1947 | rcu_read_unlock(); | |
1948 | gi->gl = NULL; | |
7c52b166 RP |
1949 | } |
1950 | ||
6802e340 | 1951 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1952 | { |
6802e340 | 1953 | return dump_glock(seq, iter_ptr); |
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 | } |