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 | ||
8f6cb409 | 176 | static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl) |
f42ab085 | 177 | { |
8f6cb409 | 178 | spin_lock(&lru_lock); |
f42ab085 SW |
179 | if (!list_empty(&gl->gl_lru)) { |
180 | list_del_init(&gl->gl_lru); | |
181 | atomic_dec(&lru_count); | |
182 | clear_bit(GLF_LRU, &gl->gl_flags); | |
183 | } | |
184 | spin_unlock(&lru_lock); | |
185 | } | |
186 | ||
b3b94faa DT |
187 | /** |
188 | * gfs2_glock_put() - Decrement reference count on glock | |
189 | * @gl: The glock to put | |
190 | * | |
191 | */ | |
192 | ||
bc015cb8 | 193 | void gfs2_glock_put(struct gfs2_glock *gl) |
b3b94faa | 194 | { |
bc015cb8 SW |
195 | struct gfs2_sbd *sdp = gl->gl_sbd; |
196 | struct address_space *mapping = gfs2_glock2aspace(gl); | |
b3b94faa | 197 | |
e66cf161 SW |
198 | if (lockref_put_or_lock(&gl->gl_lockref)) |
199 | return; | |
200 | ||
201 | lockref_mark_dead(&gl->gl_lockref); | |
202 | ||
8f6cb409 | 203 | gfs2_glock_remove_from_lru(gl); |
e66cf161 SW |
204 | spin_unlock(&gl->gl_lockref.lock); |
205 | spin_lock_bucket(gl->gl_hash); | |
206 | hlist_bl_del_rcu(&gl->gl_list); | |
207 | spin_unlock_bucket(gl->gl_hash); | |
208 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); | |
209 | GLOCK_BUG_ON(gl, mapping && mapping->nrpages); | |
210 | trace_gfs2_glock_put(gl); | |
211 | sdp->sd_lockstruct.ls_ops->lm_put_lock(gl); | |
b3b94faa DT |
212 | } |
213 | ||
b3b94faa DT |
214 | /** |
215 | * search_bucket() - Find struct gfs2_glock by lock number | |
216 | * @bucket: the bucket to search | |
217 | * @name: The lock name | |
218 | * | |
219 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
220 | */ | |
221 | ||
37b2fa6a | 222 | static struct gfs2_glock *search_bucket(unsigned int hash, |
899be4d3 | 223 | const struct gfs2_sbd *sdp, |
d6a53727 | 224 | const struct lm_lockname *name) |
b3b94faa DT |
225 | { |
226 | struct gfs2_glock *gl; | |
bc015cb8 | 227 | struct hlist_bl_node *h; |
b3b94faa | 228 | |
bc015cb8 | 229 | hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) { |
b3b94faa DT |
230 | if (!lm_name_equal(&gl->gl_name, name)) |
231 | continue; | |
899be4d3 SW |
232 | if (gl->gl_sbd != sdp) |
233 | continue; | |
e66cf161 | 234 | if (lockref_get_not_dead(&gl->gl_lockref)) |
bc015cb8 | 235 | return gl; |
b3b94faa DT |
236 | } |
237 | ||
238 | return NULL; | |
239 | } | |
240 | ||
6802e340 SW |
241 | /** |
242 | * may_grant - check if its ok to grant a new lock | |
243 | * @gl: The glock | |
244 | * @gh: The lock request which we wish to grant | |
245 | * | |
246 | * Returns: true if its ok to grant the lock | |
247 | */ | |
248 | ||
249 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) | |
250 | { | |
251 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); | |
252 | if ((gh->gh_state == LM_ST_EXCLUSIVE || | |
253 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) | |
254 | return 0; | |
255 | if (gl->gl_state == gh->gh_state) | |
256 | return 1; | |
257 | if (gh->gh_flags & GL_EXACT) | |
258 | return 0; | |
209806ab SW |
259 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
260 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) | |
261 | return 1; | |
262 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) | |
263 | return 1; | |
264 | } | |
6802e340 SW |
265 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
266 | return 1; | |
267 | return 0; | |
268 | } | |
269 | ||
270 | static void gfs2_holder_wake(struct gfs2_holder *gh) | |
271 | { | |
272 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
4e857c58 | 273 | smp_mb__after_atomic(); |
6802e340 SW |
274 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); |
275 | } | |
276 | ||
d5341a92 SW |
277 | /** |
278 | * do_error - Something unexpected has happened during a lock request | |
279 | * | |
280 | */ | |
281 | ||
282 | static inline void do_error(struct gfs2_glock *gl, const int ret) | |
283 | { | |
284 | struct gfs2_holder *gh, *tmp; | |
285 | ||
286 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
287 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
288 | continue; | |
289 | if (ret & LM_OUT_ERROR) | |
290 | gh->gh_error = -EIO; | |
291 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) | |
292 | gh->gh_error = GLR_TRYFAILED; | |
293 | else | |
294 | continue; | |
295 | list_del_init(&gh->gh_list); | |
296 | trace_gfs2_glock_queue(gh, 0); | |
297 | gfs2_holder_wake(gh); | |
298 | } | |
299 | } | |
300 | ||
6802e340 SW |
301 | /** |
302 | * do_promote - promote as many requests as possible on the current queue | |
303 | * @gl: The glock | |
304 | * | |
813e0c46 SW |
305 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
306 | * if a type specific operation is underway. | |
6802e340 SW |
307 | */ |
308 | ||
309 | static int do_promote(struct gfs2_glock *gl) | |
55ba474d HH |
310 | __releases(&gl->gl_spin) |
311 | __acquires(&gl->gl_spin) | |
6802e340 SW |
312 | { |
313 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
314 | struct gfs2_holder *gh, *tmp; | |
315 | int ret; | |
316 | ||
317 | restart: | |
318 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
319 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
320 | continue; | |
321 | if (may_grant(gl, gh)) { | |
322 | if (gh->gh_list.prev == &gl->gl_holders && | |
323 | glops->go_lock) { | |
324 | spin_unlock(&gl->gl_spin); | |
325 | /* FIXME: eliminate this eventually */ | |
326 | ret = glops->go_lock(gh); | |
327 | spin_lock(&gl->gl_spin); | |
328 | if (ret) { | |
813e0c46 SW |
329 | if (ret == 1) |
330 | return 2; | |
6802e340 SW |
331 | gh->gh_error = ret; |
332 | list_del_init(&gh->gh_list); | |
63997775 | 333 | trace_gfs2_glock_queue(gh, 0); |
6802e340 SW |
334 | gfs2_holder_wake(gh); |
335 | goto restart; | |
336 | } | |
337 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 338 | trace_gfs2_promote(gh, 1); |
6802e340 SW |
339 | gfs2_holder_wake(gh); |
340 | goto restart; | |
341 | } | |
342 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 343 | trace_gfs2_promote(gh, 0); |
6802e340 SW |
344 | gfs2_holder_wake(gh); |
345 | continue; | |
346 | } | |
347 | if (gh->gh_list.prev == &gl->gl_holders) | |
348 | return 1; | |
d5341a92 | 349 | do_error(gl, 0); |
6802e340 SW |
350 | break; |
351 | } | |
352 | return 0; | |
353 | } | |
354 | ||
6802e340 SW |
355 | /** |
356 | * find_first_waiter - find the first gh that's waiting for the glock | |
357 | * @gl: the glock | |
358 | */ | |
359 | ||
360 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) | |
361 | { | |
362 | struct gfs2_holder *gh; | |
363 | ||
364 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
365 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
366 | return gh; | |
367 | } | |
368 | return NULL; | |
369 | } | |
370 | ||
371 | /** | |
372 | * state_change - record that the glock is now in a different state | |
373 | * @gl: the glock | |
374 | * @new_state the new state | |
375 | * | |
376 | */ | |
377 | ||
378 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
379 | { | |
380 | int held1, held2; | |
381 | ||
382 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
383 | held2 = (new_state != LM_ST_UNLOCKED); | |
384 | ||
385 | if (held1 != held2) { | |
e66cf161 | 386 | GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); |
6802e340 | 387 | if (held2) |
e66cf161 | 388 | gl->gl_lockref.count++; |
6802e340 | 389 | else |
e66cf161 | 390 | gl->gl_lockref.count--; |
6802e340 | 391 | } |
7b5e3d5f SW |
392 | if (held1 && held2 && list_empty(&gl->gl_holders)) |
393 | clear_bit(GLF_QUEUED, &gl->gl_flags); | |
6802e340 | 394 | |
7cf8dcd3 BP |
395 | if (new_state != gl->gl_target) |
396 | /* shorten our minimum hold time */ | |
397 | gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR, | |
398 | GL_GLOCK_MIN_HOLD); | |
6802e340 SW |
399 | gl->gl_state = new_state; |
400 | gl->gl_tchange = jiffies; | |
401 | } | |
402 | ||
403 | static void gfs2_demote_wake(struct gfs2_glock *gl) | |
404 | { | |
405 | gl->gl_demote_state = LM_ST_EXCLUSIVE; | |
406 | clear_bit(GLF_DEMOTE, &gl->gl_flags); | |
4e857c58 | 407 | smp_mb__after_atomic(); |
6802e340 SW |
408 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); |
409 | } | |
410 | ||
411 | /** | |
412 | * finish_xmote - The DLM has replied to one of our lock requests | |
413 | * @gl: The glock | |
414 | * @ret: The status from the DLM | |
415 | * | |
416 | */ | |
417 | ||
418 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) | |
419 | { | |
420 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
421 | struct gfs2_holder *gh; | |
422 | unsigned state = ret & LM_OUT_ST_MASK; | |
813e0c46 | 423 | int rv; |
6802e340 SW |
424 | |
425 | spin_lock(&gl->gl_spin); | |
63997775 | 426 | trace_gfs2_glock_state_change(gl, state); |
6802e340 SW |
427 | state_change(gl, state); |
428 | gh = find_first_waiter(gl); | |
429 | ||
430 | /* Demote to UN request arrived during demote to SH or DF */ | |
431 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && | |
432 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) | |
433 | gl->gl_target = LM_ST_UNLOCKED; | |
434 | ||
435 | /* Check for state != intended state */ | |
436 | if (unlikely(state != gl->gl_target)) { | |
437 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { | |
438 | /* move to back of queue and try next entry */ | |
439 | if (ret & LM_OUT_CANCELED) { | |
440 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) | |
441 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
442 | gh = find_first_waiter(gl); | |
443 | gl->gl_target = gh->gh_state; | |
444 | goto retry; | |
445 | } | |
446 | /* Some error or failed "try lock" - report it */ | |
447 | if ((ret & LM_OUT_ERROR) || | |
448 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
449 | gl->gl_target = gl->gl_state; | |
450 | do_error(gl, ret); | |
451 | goto out; | |
452 | } | |
453 | } | |
454 | switch(state) { | |
455 | /* Unlocked due to conversion deadlock, try again */ | |
456 | case LM_ST_UNLOCKED: | |
457 | retry: | |
458 | do_xmote(gl, gh, gl->gl_target); | |
459 | break; | |
460 | /* Conversion fails, unlock and try again */ | |
461 | case LM_ST_SHARED: | |
462 | case LM_ST_DEFERRED: | |
463 | do_xmote(gl, gh, LM_ST_UNLOCKED); | |
464 | break; | |
465 | default: /* Everything else */ | |
d77d1b58 | 466 | pr_err("wanted %u got %u\n", gl->gl_target, state); |
6802e340 SW |
467 | GLOCK_BUG_ON(gl, 1); |
468 | } | |
469 | spin_unlock(&gl->gl_spin); | |
6802e340 SW |
470 | return; |
471 | } | |
472 | ||
473 | /* Fast path - we got what we asked for */ | |
474 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) | |
475 | gfs2_demote_wake(gl); | |
476 | if (state != LM_ST_UNLOCKED) { | |
477 | if (glops->go_xmote_bh) { | |
6802e340 SW |
478 | spin_unlock(&gl->gl_spin); |
479 | rv = glops->go_xmote_bh(gl, gh); | |
6802e340 SW |
480 | spin_lock(&gl->gl_spin); |
481 | if (rv) { | |
482 | do_error(gl, rv); | |
483 | goto out; | |
484 | } | |
485 | } | |
813e0c46 SW |
486 | rv = do_promote(gl); |
487 | if (rv == 2) | |
488 | goto out_locked; | |
6802e340 SW |
489 | } |
490 | out: | |
491 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
813e0c46 | 492 | out_locked: |
6802e340 | 493 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
494 | } |
495 | ||
6802e340 SW |
496 | /** |
497 | * do_xmote - Calls the DLM to change the state of a lock | |
498 | * @gl: The lock state | |
499 | * @gh: The holder (only for promotes) | |
500 | * @target: The target lock state | |
501 | * | |
502 | */ | |
503 | ||
504 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) | |
55ba474d HH |
505 | __releases(&gl->gl_spin) |
506 | __acquires(&gl->gl_spin) | |
6802e340 SW |
507 | { |
508 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
509 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
510 | unsigned int lck_flags = gh ? gh->gh_flags : 0; | |
511 | int ret; | |
512 | ||
513 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | | |
514 | LM_FLAG_PRIORITY); | |
921169ca SW |
515 | GLOCK_BUG_ON(gl, gl->gl_state == target); |
516 | GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target); | |
6802e340 SW |
517 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && |
518 | glops->go_inval) { | |
519 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
520 | do_error(gl, 0); /* Fail queued try locks */ | |
521 | } | |
47a25380 | 522 | gl->gl_req = target; |
a245769f SW |
523 | set_bit(GLF_BLOCKING, &gl->gl_flags); |
524 | if ((gl->gl_req == LM_ST_UNLOCKED) || | |
525 | (gl->gl_state == LM_ST_EXCLUSIVE) || | |
526 | (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB))) | |
527 | clear_bit(GLF_BLOCKING, &gl->gl_flags); | |
6802e340 | 528 | spin_unlock(&gl->gl_spin); |
06dfc306 BP |
529 | if (glops->go_sync) |
530 | glops->go_sync(gl); | |
6802e340 SW |
531 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
532 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); | |
533 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
534 | ||
535 | gfs2_glock_hold(gl); | |
921169ca SW |
536 | if (sdp->sd_lockstruct.ls_ops->lm_lock) { |
537 | /* lock_dlm */ | |
538 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags); | |
dba2d70c | 539 | if (ret) { |
d77d1b58 | 540 | pr_err("lm_lock ret %d\n", ret); |
dba2d70c DT |
541 | GLOCK_BUG_ON(gl, 1); |
542 | } | |
921169ca SW |
543 | } else { /* lock_nolock */ |
544 | finish_xmote(gl, target); | |
6802e340 SW |
545 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
546 | gfs2_glock_put(gl); | |
6802e340 | 547 | } |
921169ca | 548 | |
6802e340 SW |
549 | spin_lock(&gl->gl_spin); |
550 | } | |
551 | ||
552 | /** | |
553 | * find_first_holder - find the first "holder" gh | |
554 | * @gl: the glock | |
555 | */ | |
556 | ||
557 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) | |
558 | { | |
559 | struct gfs2_holder *gh; | |
560 | ||
561 | if (!list_empty(&gl->gl_holders)) { | |
562 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
563 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
564 | return gh; | |
565 | } | |
566 | return NULL; | |
567 | } | |
568 | ||
569 | /** | |
570 | * run_queue - do all outstanding tasks related to a glock | |
571 | * @gl: The glock in question | |
572 | * @nonblock: True if we must not block in run_queue | |
573 | * | |
574 | */ | |
575 | ||
576 | static void run_queue(struct gfs2_glock *gl, const int nonblock) | |
55ba474d HH |
577 | __releases(&gl->gl_spin) |
578 | __acquires(&gl->gl_spin) | |
6802e340 SW |
579 | { |
580 | struct gfs2_holder *gh = NULL; | |
813e0c46 | 581 | int ret; |
6802e340 SW |
582 | |
583 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
584 | return; | |
585 | ||
586 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); | |
587 | ||
588 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && | |
589 | gl->gl_demote_state != gl->gl_state) { | |
590 | if (find_first_holder(gl)) | |
d8348de0 | 591 | goto out_unlock; |
6802e340 SW |
592 | if (nonblock) |
593 | goto out_sched; | |
594 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); | |
265d529c | 595 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
6802e340 SW |
596 | gl->gl_target = gl->gl_demote_state; |
597 | } else { | |
598 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
599 | gfs2_demote_wake(gl); | |
813e0c46 SW |
600 | ret = do_promote(gl); |
601 | if (ret == 0) | |
d8348de0 | 602 | goto out_unlock; |
813e0c46 | 603 | if (ret == 2) |
a228df63 | 604 | goto out; |
6802e340 SW |
605 | gh = find_first_waiter(gl); |
606 | gl->gl_target = gh->gh_state; | |
607 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
608 | do_error(gl, 0); /* Fail queued try locks */ | |
609 | } | |
610 | do_xmote(gl, gh, gl->gl_target); | |
a228df63 | 611 | out: |
6802e340 SW |
612 | return; |
613 | ||
614 | out_sched: | |
7e71c55e | 615 | clear_bit(GLF_LOCK, &gl->gl_flags); |
4e857c58 | 616 | smp_mb__after_atomic(); |
e66cf161 | 617 | gl->gl_lockref.count++; |
6802e340 | 618 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 619 | gl->gl_lockref.count--; |
7e71c55e SW |
620 | return; |
621 | ||
d8348de0 | 622 | out_unlock: |
6802e340 | 623 | clear_bit(GLF_LOCK, &gl->gl_flags); |
4e857c58 | 624 | smp_mb__after_atomic(); |
7e71c55e | 625 | return; |
6802e340 SW |
626 | } |
627 | ||
b94a170e BM |
628 | static void delete_work_func(struct work_struct *work) |
629 | { | |
630 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete); | |
631 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
044b9414 | 632 | struct gfs2_inode *ip; |
b94a170e | 633 | struct inode *inode; |
044b9414 SW |
634 | u64 no_addr = gl->gl_name.ln_number; |
635 | ||
636 | ip = gl->gl_object; | |
637 | /* Note: Unsafe to dereference ip as we don't hold right refs/locks */ | |
b94a170e | 638 | |
b94a170e | 639 | if (ip) |
4667a0ec | 640 | inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1); |
044b9414 SW |
641 | else |
642 | inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED); | |
643 | if (inode && !IS_ERR(inode)) { | |
644 | d_prune_aliases(inode); | |
645 | iput(inode); | |
b94a170e BM |
646 | } |
647 | gfs2_glock_put(gl); | |
648 | } | |
649 | ||
c4f68a13 BM |
650 | static void glock_work_func(struct work_struct *work) |
651 | { | |
6802e340 | 652 | unsigned long delay = 0; |
c4f68a13 | 653 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
26bb7505 | 654 | int drop_ref = 0; |
c4f68a13 | 655 | |
26bb7505 | 656 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) { |
6802e340 | 657 | finish_xmote(gl, gl->gl_reply); |
26bb7505 SW |
658 | drop_ref = 1; |
659 | } | |
c4f68a13 | 660 | spin_lock(&gl->gl_spin); |
f90e5b5b | 661 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
265d529c SW |
662 | gl->gl_state != LM_ST_UNLOCKED && |
663 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { | |
6802e340 | 664 | unsigned long holdtime, now = jiffies; |
f90e5b5b | 665 | |
7cf8dcd3 | 666 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
6802e340 SW |
667 | if (time_before(now, holdtime)) |
668 | delay = holdtime - now; | |
f90e5b5b BP |
669 | |
670 | if (!delay) { | |
671 | clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags); | |
672 | set_bit(GLF_DEMOTE, &gl->gl_flags); | |
673 | } | |
6802e340 SW |
674 | } |
675 | run_queue(gl, 0); | |
c4f68a13 | 676 | spin_unlock(&gl->gl_spin); |
7cf8dcd3 | 677 | if (!delay) |
6802e340 | 678 | gfs2_glock_put(gl); |
7cf8dcd3 BP |
679 | else { |
680 | if (gl->gl_name.ln_type != LM_TYPE_INODE) | |
681 | delay = 0; | |
682 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
683 | gfs2_glock_put(gl); | |
684 | } | |
26bb7505 SW |
685 | if (drop_ref) |
686 | gfs2_glock_put(gl); | |
c4f68a13 BM |
687 | } |
688 | ||
b3b94faa DT |
689 | /** |
690 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
691 | * @sdp: The GFS2 superblock | |
692 | * @number: the lock number | |
693 | * @glops: The glock_operations to use | |
694 | * @create: If 0, don't create the glock if it doesn't exist | |
695 | * @glp: the glock is returned here | |
696 | * | |
697 | * This does not lock a glock, just finds/creates structures for one. | |
698 | * | |
699 | * Returns: errno | |
700 | */ | |
701 | ||
cd915493 | 702 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 | 703 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
704 | struct gfs2_glock **glp) |
705 | { | |
009d8518 | 706 | struct super_block *s = sdp->sd_vfs; |
37b2fa6a | 707 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
b3b94faa | 708 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 709 | unsigned int hash = gl_hash(sdp, &name); |
009d8518 | 710 | struct address_space *mapping; |
bc015cb8 | 711 | struct kmem_cache *cachep; |
b3b94faa | 712 | |
bc015cb8 | 713 | rcu_read_lock(); |
37b2fa6a | 714 | gl = search_bucket(hash, sdp, &name); |
bc015cb8 | 715 | rcu_read_unlock(); |
b3b94faa | 716 | |
64d576ba SW |
717 | *glp = gl; |
718 | if (gl) | |
b3b94faa | 719 | return 0; |
64d576ba SW |
720 | if (!create) |
721 | return -ENOENT; | |
b3b94faa | 722 | |
009d8518 | 723 | if (glops->go_flags & GLOF_ASPACE) |
bc015cb8 | 724 | cachep = gfs2_glock_aspace_cachep; |
009d8518 | 725 | else |
bc015cb8 | 726 | cachep = gfs2_glock_cachep; |
fe0bbd29 | 727 | gl = kmem_cache_alloc(cachep, GFP_NOFS); |
b3b94faa DT |
728 | if (!gl) |
729 | return -ENOMEM; | |
730 | ||
dba2d70c | 731 | memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); |
dba2d70c DT |
732 | |
733 | if (glops->go_flags & GLOF_LVB) { | |
fe0bbd29 | 734 | gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_NOFS); |
4e2f8849 | 735 | if (!gl->gl_lksb.sb_lvbptr) { |
dba2d70c DT |
736 | kmem_cache_free(cachep, gl); |
737 | return -ENOMEM; | |
738 | } | |
dba2d70c DT |
739 | } |
740 | ||
8f05228e | 741 | atomic_inc(&sdp->sd_glock_disposal); |
a245769f | 742 | gl->gl_sbd = sdp; |
ec45d9f5 | 743 | gl->gl_flags = 0; |
b3b94faa | 744 | gl->gl_name = name; |
e66cf161 | 745 | gl->gl_lockref.count = 1; |
b3b94faa | 746 | gl->gl_state = LM_ST_UNLOCKED; |
6802e340 | 747 | gl->gl_target = LM_ST_UNLOCKED; |
c4f68a13 | 748 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
37b2fa6a | 749 | gl->gl_hash = hash; |
b3b94faa | 750 | gl->gl_ops = glops; |
a245769f SW |
751 | gl->gl_dstamp = ktime_set(0, 0); |
752 | preempt_disable(); | |
753 | /* We use the global stats to estimate the initial per-glock stats */ | |
754 | gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type]; | |
755 | preempt_enable(); | |
756 | gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0; | |
757 | gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0; | |
c4f68a13 | 758 | gl->gl_tchange = jiffies; |
ec45d9f5 | 759 | gl->gl_object = NULL; |
7cf8dcd3 | 760 | gl->gl_hold_time = GL_GLOCK_DFT_HOLD; |
c4f68a13 | 761 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
b94a170e | 762 | INIT_WORK(&gl->gl_delete, delete_work_func); |
b3b94faa | 763 | |
009d8518 SW |
764 | mapping = gfs2_glock2aspace(gl); |
765 | if (mapping) { | |
766 | mapping->a_ops = &gfs2_meta_aops; | |
767 | mapping->host = s->s_bdev->bd_inode; | |
768 | mapping->flags = 0; | |
769 | mapping_set_gfp_mask(mapping, GFP_NOFS); | |
252aa6f5 | 770 | mapping->private_data = NULL; |
009d8518 | 771 | mapping->writeback_index = 0; |
b3b94faa DT |
772 | } |
773 | ||
bc015cb8 | 774 | spin_lock_bucket(hash); |
37b2fa6a | 775 | tmp = search_bucket(hash, sdp, &name); |
b3b94faa | 776 | if (tmp) { |
bc015cb8 | 777 | spin_unlock_bucket(hash); |
4e2f8849 | 778 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 779 | kmem_cache_free(cachep, gl); |
fc0e38da | 780 | atomic_dec(&sdp->sd_glock_disposal); |
b3b94faa DT |
781 | gl = tmp; |
782 | } else { | |
bc015cb8 SW |
783 | hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]); |
784 | spin_unlock_bucket(hash); | |
b3b94faa DT |
785 | } |
786 | ||
787 | *glp = gl; | |
788 | ||
789 | return 0; | |
b3b94faa DT |
790 | } |
791 | ||
792 | /** | |
793 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
794 | * @gl: the glock | |
795 | * @state: the state we're requesting | |
796 | * @flags: the modifier flags | |
797 | * @gh: the holder structure | |
798 | * | |
799 | */ | |
800 | ||
190562bd | 801 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
802 | struct gfs2_holder *gh) |
803 | { | |
804 | INIT_LIST_HEAD(&gh->gh_list); | |
805 | gh->gh_gl = gl; | |
d29c0afe | 806 | gh->gh_ip = _RET_IP_; |
b1e058da | 807 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
808 | gh->gh_state = state; |
809 | gh->gh_flags = flags; | |
810 | gh->gh_error = 0; | |
811 | gh->gh_iflags = 0; | |
b3b94faa DT |
812 | gfs2_glock_hold(gl); |
813 | } | |
814 | ||
815 | /** | |
816 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
817 | * @state: the state we're requesting | |
818 | * @flags: the modifier flags | |
819 | * @gh: the holder structure | |
820 | * | |
821 | * Don't mess with the glock. | |
822 | * | |
823 | */ | |
824 | ||
190562bd | 825 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
826 | { |
827 | gh->gh_state = state; | |
579b78a4 | 828 | gh->gh_flags = flags; |
3b8249f6 | 829 | gh->gh_iflags = 0; |
d29c0afe | 830 | gh->gh_ip = _RET_IP_; |
30badc95 | 831 | put_pid(gh->gh_owner_pid); |
1a0eae88 | 832 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
833 | } |
834 | ||
835 | /** | |
836 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
837 | * @gh: the holder structure | |
838 | * | |
839 | */ | |
840 | ||
841 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
842 | { | |
b1e058da | 843 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
844 | gfs2_glock_put(gh->gh_gl); |
845 | gh->gh_gl = NULL; | |
d0dc80db | 846 | gh->gh_ip = 0; |
b3b94faa DT |
847 | } |
848 | ||
07a79049 BP |
849 | /** |
850 | * gfs2_glock_wait - wait on a glock acquisition | |
851 | * @gh: the glock holder | |
852 | * | |
853 | * Returns: 0 on success | |
854 | */ | |
855 | ||
856 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
da755fdb | 857 | { |
7cf8dcd3 BP |
858 | unsigned long time1 = jiffies; |
859 | ||
6802e340 | 860 | might_sleep(); |
74316201 | 861 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE); |
7cf8dcd3 BP |
862 | if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */ |
863 | /* Lengthen the minimum hold time. */ | |
864 | gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time + | |
865 | GL_GLOCK_HOLD_INCR, | |
866 | GL_GLOCK_MAX_HOLD); | |
07a79049 | 867 | return gh->gh_error; |
da755fdb SW |
868 | } |
869 | ||
b3b94faa | 870 | /** |
6802e340 SW |
871 | * handle_callback - process a demote request |
872 | * @gl: the glock | |
873 | * @state: the state the caller wants us to change to | |
b3b94faa | 874 | * |
6802e340 SW |
875 | * There are only two requests that we are going to see in actual |
876 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
877 | */ |
878 | ||
6802e340 | 879 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
81ffbf65 | 880 | unsigned long delay, bool remote) |
b3b94faa | 881 | { |
6802e340 | 882 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 883 | |
6802e340 SW |
884 | set_bit(bit, &gl->gl_flags); |
885 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
886 | gl->gl_demote_state = state; | |
887 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
888 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
889 | gl->gl_demote_state != state) { | |
890 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 891 | } |
b94a170e | 892 | if (gl->gl_ops->go_callback) |
81ffbf65 | 893 | gl->gl_ops->go_callback(gl, remote); |
7bd8b2eb | 894 | trace_gfs2_demote_rq(gl, remote); |
b3b94faa DT |
895 | } |
896 | ||
6802e340 | 897 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 | 898 | { |
5e69069c | 899 | struct va_format vaf; |
7c52b166 RP |
900 | va_list args; |
901 | ||
902 | va_start(args, fmt); | |
5e69069c | 903 | |
6802e340 | 904 | if (seq) { |
1bb49303 | 905 | seq_vprintf(seq, fmt, args); |
6802e340 | 906 | } else { |
5e69069c JP |
907 | vaf.fmt = fmt; |
908 | vaf.va = &args; | |
909 | ||
d77d1b58 | 910 | pr_err("%pV", &vaf); |
6802e340 | 911 | } |
5e69069c | 912 | |
7c52b166 RP |
913 | va_end(args); |
914 | } | |
915 | ||
b3b94faa DT |
916 | /** |
917 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
918 | * @gh: the holder structure to add | |
919 | * | |
6802e340 SW |
920 | * Eventually we should move the recursive locking trap to a |
921 | * debugging option or something like that. This is the fast | |
922 | * path and needs to have the minimum number of distractions. | |
923 | * | |
b3b94faa DT |
924 | */ |
925 | ||
6802e340 | 926 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
927 | __releases(&gl->gl_spin) |
928 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
929 | { |
930 | struct gfs2_glock *gl = gh->gh_gl; | |
6802e340 SW |
931 | struct gfs2_sbd *sdp = gl->gl_sbd; |
932 | struct list_head *insert_pt = NULL; | |
933 | struct gfs2_holder *gh2; | |
e5dc76b9 | 934 | int try_futile = 0; |
b3b94faa | 935 | |
b1e058da | 936 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
937 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
938 | BUG(); | |
190562bd | 939 | |
6802e340 SW |
940 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
941 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
e5dc76b9 | 942 | try_futile = !may_grant(gl, gh); |
6802e340 SW |
943 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
944 | goto fail; | |
945 | } | |
946 | ||
947 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
948 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
949 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
950 | goto trap_recursive; | |
e5dc76b9 BP |
951 | if (try_futile && |
952 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
6802e340 SW |
953 | fail: |
954 | gh->gh_error = GLR_TRYFAILED; | |
955 | gfs2_holder_wake(gh); | |
956 | return; | |
b4c20166 | 957 | } |
6802e340 SW |
958 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
959 | continue; | |
960 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
961 | insert_pt = &gh2->gh_list; | |
962 | } | |
7b5e3d5f | 963 | set_bit(GLF_QUEUED, &gl->gl_flags); |
edae38a6 | 964 | trace_gfs2_glock_queue(gh, 1); |
a245769f SW |
965 | gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT); |
966 | gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT); | |
6802e340 SW |
967 | if (likely(insert_pt == NULL)) { |
968 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
969 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
970 | goto do_cancel; | |
971 | return; | |
972 | } | |
973 | list_add_tail(&gh->gh_list, insert_pt); | |
974 | do_cancel: | |
975 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
976 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
977 | spin_unlock(&gl->gl_spin); | |
048bca22 | 978 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
f057f6cd | 979 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
6802e340 | 980 | spin_lock(&gl->gl_spin); |
b3b94faa | 981 | } |
6802e340 | 982 | return; |
b3b94faa | 983 | |
6802e340 | 984 | trap_recursive: |
fc554ed3 FF |
985 | pr_err("original: %pSR\n", (void *)gh2->gh_ip); |
986 | pr_err("pid: %d\n", pid_nr(gh2->gh_owner_pid)); | |
987 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 988 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); |
fc554ed3 FF |
989 | pr_err("new: %pSR\n", (void *)gh->gh_ip); |
990 | pr_err("pid: %d\n", pid_nr(gh->gh_owner_pid)); | |
991 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 992 | gh->gh_gl->gl_name.ln_type, gh->gh_state); |
8eae1ca0 | 993 | gfs2_dump_glock(NULL, gl); |
6802e340 | 994 | BUG(); |
b3b94faa DT |
995 | } |
996 | ||
997 | /** | |
998 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
999 | * @gh: the holder structure | |
1000 | * | |
1001 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1002 | * | |
1003 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1004 | */ | |
1005 | ||
1006 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1007 | { | |
1008 | struct gfs2_glock *gl = gh->gh_gl; | |
1009 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1010 | int error = 0; | |
1011 | ||
6802e340 | 1012 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1013 | return -EIO; |
b3b94faa | 1014 | |
f42ab085 SW |
1015 | if (test_bit(GLF_LRU, &gl->gl_flags)) |
1016 | gfs2_glock_remove_from_lru(gl); | |
1017 | ||
b3b94faa DT |
1018 | spin_lock(&gl->gl_spin); |
1019 | add_to_queue(gh); | |
01b172b7 BP |
1020 | if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) && |
1021 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) { | |
0809f6ec | 1022 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
01b172b7 BP |
1023 | gl->gl_lockref.count++; |
1024 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1025 | gl->gl_lockref.count--; | |
1026 | } | |
6802e340 | 1027 | run_queue(gl, 1); |
b3b94faa DT |
1028 | spin_unlock(&gl->gl_spin); |
1029 | ||
6802e340 SW |
1030 | if (!(gh->gh_flags & GL_ASYNC)) |
1031 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1032 | |
b3b94faa DT |
1033 | return error; |
1034 | } | |
1035 | ||
1036 | /** | |
1037 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1038 | * @gh: the holder | |
1039 | * | |
1040 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1041 | */ | |
1042 | ||
1043 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1044 | { | |
6802e340 | 1045 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1046 | } |
1047 | ||
1048 | /** | |
1049 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1050 | * @gh: the glock holder | |
1051 | * | |
1052 | */ | |
1053 | ||
1054 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1055 | { | |
1056 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1057 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1058 | unsigned delay = 0; |
6802e340 | 1059 | int fast_path = 0; |
b3b94faa | 1060 | |
6802e340 | 1061 | spin_lock(&gl->gl_spin); |
b3b94faa | 1062 | if (gh->gh_flags & GL_NOCACHE) |
81ffbf65 | 1063 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
b3b94faa | 1064 | |
b3b94faa | 1065 | list_del_init(&gh->gh_list); |
6802e340 | 1066 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1067 | if (glops->go_unlock) { |
6802e340 | 1068 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1069 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1070 | glops->go_unlock(gh); |
3042a2cc | 1071 | spin_lock(&gl->gl_spin); |
6802e340 | 1072 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1073 | } |
6802e340 SW |
1074 | if (list_empty(&gl->gl_holders) && |
1075 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1076 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1077 | fast_path = 1; | |
b3b94faa | 1078 | } |
e7ccaf5f BP |
1079 | if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl) && |
1080 | (glops->go_flags & GLOF_LRU)) | |
4abb6ad9 BP |
1081 | gfs2_glock_add_to_lru(gl); |
1082 | ||
63997775 | 1083 | trace_gfs2_glock_queue(gh, 0); |
b3b94faa | 1084 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1085 | if (likely(fast_path)) |
1086 | return; | |
c4f68a13 BM |
1087 | |
1088 | gfs2_glock_hold(gl); | |
1089 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
7cf8dcd3 BP |
1090 | !test_bit(GLF_DEMOTE, &gl->gl_flags) && |
1091 | gl->gl_name.ln_type == LM_TYPE_INODE) | |
1092 | delay = gl->gl_hold_time; | |
c4f68a13 BM |
1093 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1094 | gfs2_glock_put(gl); | |
b3b94faa DT |
1095 | } |
1096 | ||
d93cfa98 AD |
1097 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1098 | { | |
1099 | struct gfs2_glock *gl = gh->gh_gl; | |
1100 | gfs2_glock_dq(gh); | |
81e1d450 | 1101 | might_sleep(); |
74316201 | 1102 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE); |
d93cfa98 AD |
1103 | } |
1104 | ||
b3b94faa DT |
1105 | /** |
1106 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1107 | * @gh: the holder structure | |
1108 | * | |
1109 | */ | |
1110 | ||
1111 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1112 | { | |
1113 | gfs2_glock_dq(gh); | |
1114 | gfs2_holder_uninit(gh); | |
1115 | } | |
1116 | ||
1117 | /** | |
1118 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1119 | * @sdp: the filesystem | |
1120 | * @number: the lock number | |
1121 | * @glops: the glock operations for the type of glock | |
1122 | * @state: the state to acquire the glock in | |
25985edc | 1123 | * @flags: modifier flags for the acquisition |
b3b94faa DT |
1124 | * @gh: the struct gfs2_holder |
1125 | * | |
1126 | * Returns: errno | |
1127 | */ | |
1128 | ||
cd915493 | 1129 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1130 | const struct gfs2_glock_operations *glops, |
1131 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1132 | { |
1133 | struct gfs2_glock *gl; | |
1134 | int error; | |
1135 | ||
1136 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1137 | if (!error) { | |
1138 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1139 | gfs2_glock_put(gl); | |
1140 | } | |
1141 | ||
1142 | return error; | |
1143 | } | |
1144 | ||
1145 | /** | |
1146 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1147 | * @arg_a: the first structure | |
1148 | * @arg_b: the second structure | |
1149 | * | |
1150 | */ | |
1151 | ||
1152 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1153 | { | |
a5e08a9e SW |
1154 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1155 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1156 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1157 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1158 | |
1159 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1160 | return 1; |
1161 | if (a->ln_number < b->ln_number) | |
1162 | return -1; | |
1c0f4872 | 1163 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1164 | return 0; |
b3b94faa DT |
1165 | } |
1166 | ||
1167 | /** | |
1168 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1169 | * @num_gh: the number of structures | |
1170 | * @ghs: an array of struct gfs2_holder structures | |
1171 | * | |
1172 | * Returns: 0 on success (all glocks acquired), | |
1173 | * errno on failure (no glocks acquired) | |
1174 | */ | |
1175 | ||
1176 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1177 | struct gfs2_holder **p) | |
1178 | { | |
1179 | unsigned int x; | |
1180 | int error = 0; | |
1181 | ||
1182 | for (x = 0; x < num_gh; x++) | |
1183 | p[x] = &ghs[x]; | |
1184 | ||
1185 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1186 | ||
1187 | for (x = 0; x < num_gh; x++) { | |
1188 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1189 | ||
1190 | error = gfs2_glock_nq(p[x]); | |
1191 | if (error) { | |
1192 | while (x--) | |
1193 | gfs2_glock_dq(p[x]); | |
1194 | break; | |
1195 | } | |
1196 | } | |
1197 | ||
1198 | return error; | |
1199 | } | |
1200 | ||
1201 | /** | |
1202 | * gfs2_glock_nq_m - acquire multiple glocks | |
1203 | * @num_gh: the number of structures | |
1204 | * @ghs: an array of struct gfs2_holder structures | |
1205 | * | |
b3b94faa DT |
1206 | * |
1207 | * Returns: 0 on success (all glocks acquired), | |
1208 | * errno on failure (no glocks acquired) | |
1209 | */ | |
1210 | ||
1211 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1212 | { | |
eaf5bd3c SW |
1213 | struct gfs2_holder *tmp[4]; |
1214 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1215 | int error = 0; |
1216 | ||
eaf5bd3c SW |
1217 | switch(num_gh) { |
1218 | case 0: | |
b3b94faa | 1219 | return 0; |
eaf5bd3c | 1220 | case 1: |
b3b94faa DT |
1221 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1222 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1223 | default: |
1224 | if (num_gh <= 4) | |
b3b94faa | 1225 | break; |
eaf5bd3c SW |
1226 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1227 | if (!pph) | |
1228 | return -ENOMEM; | |
b3b94faa DT |
1229 | } |
1230 | ||
eaf5bd3c | 1231 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1232 | |
eaf5bd3c SW |
1233 | if (pph != tmp) |
1234 | kfree(pph); | |
b3b94faa DT |
1235 | |
1236 | return error; | |
1237 | } | |
1238 | ||
1239 | /** | |
1240 | * gfs2_glock_dq_m - release multiple glocks | |
1241 | * @num_gh: the number of structures | |
1242 | * @ghs: an array of struct gfs2_holder structures | |
1243 | * | |
1244 | */ | |
1245 | ||
1246 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1247 | { | |
fa1bbdea BP |
1248 | while (num_gh--) |
1249 | gfs2_glock_dq(&ghs[num_gh]); | |
b3b94faa DT |
1250 | } |
1251 | ||
f057f6cd | 1252 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
da755fdb | 1253 | { |
c4f68a13 BM |
1254 | unsigned long delay = 0; |
1255 | unsigned long holdtime; | |
1256 | unsigned long now = jiffies; | |
b3b94faa | 1257 | |
f057f6cd | 1258 | gfs2_glock_hold(gl); |
7cf8dcd3 BP |
1259 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
1260 | if (test_bit(GLF_QUEUED, &gl->gl_flags) && | |
1261 | gl->gl_name.ln_type == LM_TYPE_INODE) { | |
7b5e3d5f SW |
1262 | if (time_before(now, holdtime)) |
1263 | delay = holdtime - now; | |
1264 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) | |
7cf8dcd3 | 1265 | delay = gl->gl_hold_time; |
7b5e3d5f | 1266 | } |
b3b94faa | 1267 | |
6802e340 | 1268 | spin_lock(&gl->gl_spin); |
81ffbf65 | 1269 | handle_callback(gl, state, delay, true); |
6802e340 | 1270 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1271 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1272 | gfs2_glock_put(gl); | |
b3b94faa DT |
1273 | } |
1274 | ||
0809f6ec SW |
1275 | /** |
1276 | * gfs2_should_freeze - Figure out if glock should be frozen | |
1277 | * @gl: The glock in question | |
1278 | * | |
1279 | * Glocks are not frozen if (a) the result of the dlm operation is | |
1280 | * an error, (b) the locking operation was an unlock operation or | |
1281 | * (c) if there is a "noexp" flagged request anywhere in the queue | |
1282 | * | |
1283 | * Returns: 1 if freezing should occur, 0 otherwise | |
1284 | */ | |
1285 | ||
1286 | static int gfs2_should_freeze(const struct gfs2_glock *gl) | |
1287 | { | |
1288 | const struct gfs2_holder *gh; | |
1289 | ||
1290 | if (gl->gl_reply & ~LM_OUT_ST_MASK) | |
1291 | return 0; | |
1292 | if (gl->gl_target == LM_ST_UNLOCKED) | |
1293 | return 0; | |
1294 | ||
1295 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
1296 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1297 | continue; | |
1298 | if (LM_FLAG_NOEXP & gh->gh_flags) | |
1299 | return 0; | |
1300 | } | |
1301 | ||
1302 | return 1; | |
1303 | } | |
1304 | ||
b3b94faa | 1305 | /** |
f057f6cd SW |
1306 | * gfs2_glock_complete - Callback used by locking |
1307 | * @gl: Pointer to the glock | |
1308 | * @ret: The return value from the dlm | |
b3b94faa | 1309 | * |
47a25380 SW |
1310 | * The gl_reply field is under the gl_spin lock so that it is ok |
1311 | * to use a bitfield shared with other glock state fields. | |
b3b94faa DT |
1312 | */ |
1313 | ||
f057f6cd | 1314 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
b3b94faa | 1315 | { |
f057f6cd | 1316 | struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; |
0809f6ec | 1317 | |
47a25380 | 1318 | spin_lock(&gl->gl_spin); |
f057f6cd | 1319 | gl->gl_reply = ret; |
0809f6ec | 1320 | |
e0c2a9aa | 1321 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) { |
0809f6ec | 1322 | if (gfs2_should_freeze(gl)) { |
f057f6cd | 1323 | set_bit(GLF_FROZEN, &gl->gl_flags); |
0809f6ec | 1324 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1325 | return; |
0809f6ec | 1326 | } |
b3b94faa | 1327 | } |
47a25380 | 1328 | |
e66cf161 | 1329 | gl->gl_lockref.count++; |
f057f6cd | 1330 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
e66cf161 SW |
1331 | spin_unlock(&gl->gl_spin); |
1332 | ||
f057f6cd SW |
1333 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1334 | gfs2_glock_put(gl); | |
b3b94faa DT |
1335 | } |
1336 | ||
4506a519 SW |
1337 | static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) |
1338 | { | |
1339 | struct gfs2_glock *gla, *glb; | |
1340 | ||
1341 | gla = list_entry(a, struct gfs2_glock, gl_lru); | |
1342 | glb = list_entry(b, struct gfs2_glock, gl_lru); | |
1343 | ||
1344 | if (gla->gl_name.ln_number > glb->gl_name.ln_number) | |
1345 | return 1; | |
1346 | if (gla->gl_name.ln_number < glb->gl_name.ln_number) | |
1347 | return -1; | |
1348 | ||
1349 | return 0; | |
1350 | } | |
1351 | ||
1352 | /** | |
1353 | * gfs2_dispose_glock_lru - Demote a list of glocks | |
1354 | * @list: The list to dispose of | |
1355 | * | |
1356 | * Disposing of glocks may involve disk accesses, so that here we sort | |
1357 | * the glocks by number (i.e. disk location of the inodes) so that if | |
1358 | * there are any such accesses, they'll be sent in order (mostly). | |
1359 | * | |
1360 | * Must be called under the lru_lock, but may drop and retake this | |
1361 | * lock. While the lru_lock is dropped, entries may vanish from the | |
1362 | * list, but no new entries will appear on the list (since it is | |
1363 | * private) | |
1364 | */ | |
1365 | ||
1366 | static void gfs2_dispose_glock_lru(struct list_head *list) | |
1367 | __releases(&lru_lock) | |
1368 | __acquires(&lru_lock) | |
1369 | { | |
1370 | struct gfs2_glock *gl; | |
1371 | ||
1372 | list_sort(NULL, list, glock_cmp); | |
1373 | ||
1374 | while(!list_empty(list)) { | |
1375 | gl = list_entry(list->next, struct gfs2_glock, gl_lru); | |
1376 | list_del_init(&gl->gl_lru); | |
e66cf161 | 1377 | if (!spin_trylock(&gl->gl_spin)) { |
94a09a39 | 1378 | add_back_to_lru: |
e66cf161 SW |
1379 | list_add(&gl->gl_lru, &lru_list); |
1380 | atomic_inc(&lru_count); | |
1381 | continue; | |
1382 | } | |
94a09a39 SW |
1383 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
1384 | spin_unlock(&gl->gl_spin); | |
1385 | goto add_back_to_lru; | |
1386 | } | |
4506a519 | 1387 | clear_bit(GLF_LRU, &gl->gl_flags); |
e66cf161 | 1388 | gl->gl_lockref.count++; |
4506a519 | 1389 | if (demote_ok(gl)) |
81ffbf65 | 1390 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
4506a519 | 1391 | WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); |
4506a519 | 1392 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 1393 | gl->gl_lockref.count--; |
4506a519 | 1394 | spin_unlock(&gl->gl_spin); |
94a09a39 | 1395 | cond_resched_lock(&lru_lock); |
4506a519 SW |
1396 | } |
1397 | } | |
1398 | ||
2a005855 SW |
1399 | /** |
1400 | * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote | |
1401 | * @nr: The number of entries to scan | |
1402 | * | |
4506a519 SW |
1403 | * This function selects the entries on the LRU which are able to |
1404 | * be demoted, and then kicks off the process by calling | |
1405 | * gfs2_dispose_glock_lru() above. | |
2a005855 | 1406 | */ |
b3b94faa | 1407 | |
1ab6c499 | 1408 | static long gfs2_scan_glock_lru(int nr) |
b3b94faa DT |
1409 | { |
1410 | struct gfs2_glock *gl; | |
97cc1025 | 1411 | LIST_HEAD(skipped); |
4506a519 | 1412 | LIST_HEAD(dispose); |
1ab6c499 | 1413 | long freed = 0; |
b3b94faa | 1414 | |
97cc1025 | 1415 | spin_lock(&lru_lock); |
1ab6c499 | 1416 | while ((nr-- >= 0) && !list_empty(&lru_list)) { |
97cc1025 | 1417 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); |
97cc1025 SW |
1418 | |
1419 | /* Test for being demotable */ | |
94a09a39 | 1420 | if (!test_bit(GLF_LOCK, &gl->gl_flags)) { |
4506a519 SW |
1421 | list_move(&gl->gl_lru, &dispose); |
1422 | atomic_dec(&lru_count); | |
1ab6c499 | 1423 | freed++; |
2163b1e6 | 1424 | continue; |
97cc1025 | 1425 | } |
4506a519 SW |
1426 | |
1427 | list_move(&gl->gl_lru, &skipped); | |
b3b94faa | 1428 | } |
97cc1025 | 1429 | list_splice(&skipped, &lru_list); |
4506a519 SW |
1430 | if (!list_empty(&dispose)) |
1431 | gfs2_dispose_glock_lru(&dispose); | |
97cc1025 | 1432 | spin_unlock(&lru_lock); |
1ab6c499 DC |
1433 | |
1434 | return freed; | |
2a005855 SW |
1435 | } |
1436 | ||
1ab6c499 DC |
1437 | static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink, |
1438 | struct shrink_control *sc) | |
2a005855 | 1439 | { |
1ab6c499 DC |
1440 | if (!(sc->gfp_mask & __GFP_FS)) |
1441 | return SHRINK_STOP; | |
1442 | return gfs2_scan_glock_lru(sc->nr_to_scan); | |
1443 | } | |
2a005855 | 1444 | |
1ab6c499 DC |
1445 | static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink, |
1446 | struct shrink_control *sc) | |
1447 | { | |
55f841ce | 1448 | return vfs_pressure_ratio(atomic_read(&lru_count)); |
b3b94faa DT |
1449 | } |
1450 | ||
97cc1025 | 1451 | static struct shrinker glock_shrinker = { |
97cc1025 | 1452 | .seeks = DEFAULT_SEEKS, |
1ab6c499 DC |
1453 | .count_objects = gfs2_glock_shrink_count, |
1454 | .scan_objects = gfs2_glock_shrink_scan, | |
97cc1025 SW |
1455 | }; |
1456 | ||
b3b94faa DT |
1457 | /** |
1458 | * examine_bucket - Call a function for glock in a hash bucket | |
1459 | * @examiner: the function | |
1460 | * @sdp: the filesystem | |
1461 | * @bucket: the bucket | |
1462 | * | |
b3b94faa DT |
1463 | */ |
1464 | ||
bc015cb8 | 1465 | static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, |
37b2fa6a | 1466 | unsigned int hash) |
b3b94faa | 1467 | { |
bc015cb8 SW |
1468 | struct gfs2_glock *gl; |
1469 | struct hlist_bl_head *head = &gl_hash_table[hash]; | |
1470 | struct hlist_bl_node *pos; | |
b3b94faa | 1471 | |
bc015cb8 SW |
1472 | rcu_read_lock(); |
1473 | hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { | |
e66cf161 | 1474 | if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref)) |
24264434 | 1475 | examiner(gl); |
b3b94faa | 1476 | } |
bc015cb8 | 1477 | rcu_read_unlock(); |
8fbbfd21 | 1478 | cond_resched(); |
bc015cb8 SW |
1479 | } |
1480 | ||
1481 | static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp) | |
1482 | { | |
1483 | unsigned x; | |
1484 | ||
1485 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
1486 | examine_bucket(examiner, sdp, x); | |
b3b94faa DT |
1487 | } |
1488 | ||
f057f6cd SW |
1489 | |
1490 | /** | |
1491 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting | |
1492 | * @gl: The glock to thaw | |
1493 | * | |
f057f6cd SW |
1494 | */ |
1495 | ||
1496 | static void thaw_glock(struct gfs2_glock *gl) | |
1497 | { | |
1498 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
7286b31e | 1499 | goto out; |
f057f6cd | 1500 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
7286b31e SW |
1501 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) { |
1502 | out: | |
f057f6cd | 1503 | gfs2_glock_put(gl); |
7286b31e | 1504 | } |
f057f6cd SW |
1505 | } |
1506 | ||
b3b94faa DT |
1507 | /** |
1508 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1509 | * @gl: the glock to look at | |
1510 | * | |
1511 | */ | |
1512 | ||
1513 | static void clear_glock(struct gfs2_glock *gl) | |
1514 | { | |
f42ab085 | 1515 | gfs2_glock_remove_from_lru(gl); |
b3b94faa | 1516 | |
6802e340 | 1517 | spin_lock(&gl->gl_spin); |
c741c455 | 1518 | if (gl->gl_state != LM_ST_UNLOCKED) |
81ffbf65 | 1519 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
6802e340 | 1520 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1521 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1522 | gfs2_glock_put(gl); | |
b3b94faa DT |
1523 | } |
1524 | ||
f057f6cd SW |
1525 | /** |
1526 | * gfs2_glock_thaw - Thaw any frozen glocks | |
1527 | * @sdp: The super block | |
1528 | * | |
1529 | */ | |
1530 | ||
1531 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) | |
1532 | { | |
bc015cb8 SW |
1533 | glock_hash_walk(thaw_glock, sdp); |
1534 | } | |
f057f6cd | 1535 | |
ac3beb6a | 1536 | static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
bc015cb8 | 1537 | { |
bc015cb8 | 1538 | spin_lock(&gl->gl_spin); |
ac3beb6a | 1539 | gfs2_dump_glock(seq, gl); |
bc015cb8 | 1540 | spin_unlock(&gl->gl_spin); |
bc015cb8 SW |
1541 | } |
1542 | ||
1543 | static void dump_glock_func(struct gfs2_glock *gl) | |
1544 | { | |
1545 | dump_glock(NULL, gl); | |
f057f6cd SW |
1546 | } |
1547 | ||
b3b94faa DT |
1548 | /** |
1549 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1550 | * @sdp: the filesystem | |
1551 | * @wait: wait until it's all gone | |
1552 | * | |
1bdad606 | 1553 | * Called when unmounting the filesystem. |
b3b94faa DT |
1554 | */ |
1555 | ||
fefc03bf | 1556 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa | 1557 | { |
fb6791d1 | 1558 | set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags); |
222cb538 | 1559 | flush_workqueue(glock_workqueue); |
bc015cb8 | 1560 | glock_hash_walk(clear_glock, sdp); |
8f05228e SW |
1561 | flush_workqueue(glock_workqueue); |
1562 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); | |
bc015cb8 | 1563 | glock_hash_walk(dump_glock_func, sdp); |
b3b94faa DT |
1564 | } |
1565 | ||
813e0c46 SW |
1566 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1567 | { | |
1568 | struct gfs2_glock *gl = ip->i_gl; | |
1569 | int ret; | |
1570 | ||
1571 | ret = gfs2_truncatei_resume(ip); | |
1572 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); | |
1573 | ||
1574 | spin_lock(&gl->gl_spin); | |
1575 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1576 | run_queue(gl, 1); | |
1577 | spin_unlock(&gl->gl_spin); | |
1578 | } | |
1579 | ||
6802e340 | 1580 | static const char *state2str(unsigned state) |
04b933f2 | 1581 | { |
6802e340 SW |
1582 | switch(state) { |
1583 | case LM_ST_UNLOCKED: | |
1584 | return "UN"; | |
1585 | case LM_ST_SHARED: | |
1586 | return "SH"; | |
1587 | case LM_ST_DEFERRED: | |
1588 | return "DF"; | |
1589 | case LM_ST_EXCLUSIVE: | |
1590 | return "EX"; | |
1591 | } | |
1592 | return "??"; | |
1593 | } | |
1594 | ||
1595 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1596 | { | |
1597 | char *p = buf; | |
1598 | if (flags & LM_FLAG_TRY) | |
1599 | *p++ = 't'; | |
1600 | if (flags & LM_FLAG_TRY_1CB) | |
1601 | *p++ = 'T'; | |
1602 | if (flags & LM_FLAG_NOEXP) | |
1603 | *p++ = 'e'; | |
1604 | if (flags & LM_FLAG_ANY) | |
f057f6cd | 1605 | *p++ = 'A'; |
6802e340 SW |
1606 | if (flags & LM_FLAG_PRIORITY) |
1607 | *p++ = 'p'; | |
1608 | if (flags & GL_ASYNC) | |
1609 | *p++ = 'a'; | |
1610 | if (flags & GL_EXACT) | |
1611 | *p++ = 'E'; | |
6802e340 SW |
1612 | if (flags & GL_NOCACHE) |
1613 | *p++ = 'c'; | |
1614 | if (test_bit(HIF_HOLDER, &iflags)) | |
1615 | *p++ = 'H'; | |
1616 | if (test_bit(HIF_WAIT, &iflags)) | |
1617 | *p++ = 'W'; | |
1618 | if (test_bit(HIF_FIRST, &iflags)) | |
1619 | *p++ = 'F'; | |
1620 | *p = 0; | |
1621 | return buf; | |
04b933f2 RP |
1622 | } |
1623 | ||
b3b94faa DT |
1624 | /** |
1625 | * dump_holder - print information about a glock holder | |
6802e340 | 1626 | * @seq: the seq_file struct |
b3b94faa DT |
1627 | * @gh: the glock holder |
1628 | * | |
b3b94faa DT |
1629 | */ |
1630 | ||
ac3beb6a | 1631 | static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1632 | { |
6802e340 | 1633 | struct task_struct *gh_owner = NULL; |
6802e340 | 1634 | char flags_buf[32]; |
b3b94faa | 1635 | |
0b3a2c99 | 1636 | rcu_read_lock(); |
6802e340 | 1637 | if (gh->gh_owner_pid) |
b1e058da | 1638 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
cc18152e JP |
1639 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
1640 | state2str(gh->gh_state), | |
1641 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1642 | gh->gh_error, | |
1643 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1644 | gh_owner ? gh_owner->comm : "(ended)", | |
1645 | (void *)gh->gh_ip); | |
0b3a2c99 | 1646 | rcu_read_unlock(); |
b3b94faa DT |
1647 | } |
1648 | ||
627c10b7 | 1649 | static const char *gflags2str(char *buf, const struct gfs2_glock *gl) |
6802e340 | 1650 | { |
627c10b7 | 1651 | const unsigned long *gflags = &gl->gl_flags; |
6802e340 | 1652 | char *p = buf; |
627c10b7 | 1653 | |
6802e340 SW |
1654 | if (test_bit(GLF_LOCK, gflags)) |
1655 | *p++ = 'l'; | |
6802e340 SW |
1656 | if (test_bit(GLF_DEMOTE, gflags)) |
1657 | *p++ = 'D'; | |
1658 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1659 | *p++ = 'd'; | |
1660 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1661 | *p++ = 'p'; | |
1662 | if (test_bit(GLF_DIRTY, gflags)) | |
1663 | *p++ = 'y'; | |
1664 | if (test_bit(GLF_LFLUSH, gflags)) | |
1665 | *p++ = 'f'; | |
1666 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1667 | *p++ = 'i'; | |
1668 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1669 | *p++ = 'r'; | |
f057f6cd | 1670 | if (test_bit(GLF_INITIAL, gflags)) |
d8348de0 | 1671 | *p++ = 'I'; |
f057f6cd SW |
1672 | if (test_bit(GLF_FROZEN, gflags)) |
1673 | *p++ = 'F'; | |
7b5e3d5f SW |
1674 | if (test_bit(GLF_QUEUED, gflags)) |
1675 | *p++ = 'q'; | |
627c10b7 SW |
1676 | if (test_bit(GLF_LRU, gflags)) |
1677 | *p++ = 'L'; | |
1678 | if (gl->gl_object) | |
1679 | *p++ = 'o'; | |
a245769f SW |
1680 | if (test_bit(GLF_BLOCKING, gflags)) |
1681 | *p++ = 'b'; | |
6802e340 SW |
1682 | *p = 0; |
1683 | return buf; | |
b3b94faa DT |
1684 | } |
1685 | ||
1686 | /** | |
8eae1ca0 | 1687 | * gfs2_dump_glock - print information about a glock |
6802e340 | 1688 | * @seq: The seq_file struct |
b3b94faa | 1689 | * @gl: the glock |
6802e340 SW |
1690 | * |
1691 | * The file format is as follows: | |
1692 | * One line per object, capital letters are used to indicate objects | |
1693 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1694 | * other objects are indented by a single space and follow the glock to | |
1695 | * which they are related. Fields are indicated by lower case letters | |
1696 | * followed by a colon and the field value, except for strings which are in | |
1697 | * [] so that its possible to see if they are composed of spaces for | |
1698 | * example. The field's are n = number (id of the object), f = flags, | |
1699 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa | 1700 | * |
b3b94faa DT |
1701 | */ |
1702 | ||
ac3beb6a | 1703 | void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1704 | { |
6802e340 SW |
1705 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1706 | unsigned long long dtime; | |
1707 | const struct gfs2_holder *gh; | |
1708 | char gflags_buf[32]; | |
b3b94faa | 1709 | |
6802e340 SW |
1710 | dtime = jiffies - gl->gl_demote_time; |
1711 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1712 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1713 | dtime = 0; | |
7cf8dcd3 | 1714 | 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 |
1715 | state2str(gl->gl_state), |
1716 | gl->gl_name.ln_type, | |
1717 | (unsigned long long)gl->gl_name.ln_number, | |
627c10b7 | 1718 | gflags2str(gflags_buf, gl), |
6802e340 SW |
1719 | state2str(gl->gl_target), |
1720 | state2str(gl->gl_demote_state), dtime, | |
6802e340 | 1721 | atomic_read(&gl->gl_ail_count), |
f42ab085 | 1722 | atomic_read(&gl->gl_revokes), |
e66cf161 | 1723 | (int)gl->gl_lockref.count, gl->gl_hold_time); |
b3b94faa | 1724 | |
ac3beb6a SW |
1725 | list_for_each_entry(gh, &gl->gl_holders, gh_list) |
1726 | dump_holder(seq, gh); | |
1727 | ||
6802e340 | 1728 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
ac3beb6a | 1729 | glops->go_dump(seq, gl); |
b3b94faa DT |
1730 | } |
1731 | ||
a245769f SW |
1732 | static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr) |
1733 | { | |
1734 | struct gfs2_glock *gl = iter_ptr; | |
1735 | ||
1736 | seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n", | |
1737 | gl->gl_name.ln_type, | |
1738 | (unsigned long long)gl->gl_name.ln_number, | |
1739 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTT], | |
1740 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR], | |
1741 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB], | |
1742 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB], | |
1743 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRT], | |
1744 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR], | |
1745 | (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT], | |
1746 | (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]); | |
1747 | return 0; | |
1748 | } | |
1749 | ||
1750 | static const char *gfs2_gltype[] = { | |
1751 | "type", | |
1752 | "reserved", | |
1753 | "nondisk", | |
1754 | "inode", | |
1755 | "rgrp", | |
1756 | "meta", | |
1757 | "iopen", | |
1758 | "flock", | |
1759 | "plock", | |
1760 | "quota", | |
1761 | "journal", | |
1762 | }; | |
1763 | ||
1764 | static const char *gfs2_stype[] = { | |
1765 | [GFS2_LKS_SRTT] = "srtt", | |
1766 | [GFS2_LKS_SRTTVAR] = "srttvar", | |
1767 | [GFS2_LKS_SRTTB] = "srttb", | |
1768 | [GFS2_LKS_SRTTVARB] = "srttvarb", | |
1769 | [GFS2_LKS_SIRT] = "sirt", | |
1770 | [GFS2_LKS_SIRTVAR] = "sirtvar", | |
1771 | [GFS2_LKS_DCOUNT] = "dlm", | |
1772 | [GFS2_LKS_QCOUNT] = "queue", | |
1773 | }; | |
1774 | ||
1775 | #define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype)) | |
1776 | ||
1777 | static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr) | |
1778 | { | |
1779 | struct gfs2_glock_iter *gi = seq->private; | |
1780 | struct gfs2_sbd *sdp = gi->sdp; | |
1781 | unsigned index = gi->hash >> 3; | |
1782 | unsigned subindex = gi->hash & 0x07; | |
1783 | s64 value; | |
1784 | int i; | |
1785 | ||
1786 | if (index == 0 && subindex != 0) | |
1787 | return 0; | |
6802e340 | 1788 | |
a245769f SW |
1789 | seq_printf(seq, "%-10s %8s:", gfs2_gltype[index], |
1790 | (index == 0) ? "cpu": gfs2_stype[subindex]); | |
b3b94faa | 1791 | |
a245769f SW |
1792 | for_each_possible_cpu(i) { |
1793 | const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i); | |
1794 | if (index == 0) { | |
1795 | value = i; | |
1796 | } else { | |
1797 | value = lkstats->lkstats[index - 1].stats[subindex]; | |
1798 | } | |
1799 | seq_printf(seq, " %15lld", (long long)value); | |
1800 | } | |
1801 | seq_putc(seq, '\n'); | |
1802 | return 0; | |
1803 | } | |
8fbbfd21 | 1804 | |
85d1da67 SW |
1805 | int __init gfs2_glock_init(void) |
1806 | { | |
1807 | unsigned i; | |
1808 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
bc015cb8 | 1809 | INIT_HLIST_BL_HEAD(&gl_hash_table[i]); |
087efdd3 | 1810 | } |
8fbbfd21 | 1811 | |
d2115778 | 1812 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
58a69cb4 | 1813 | WQ_HIGHPRI | WQ_FREEZABLE, 0); |
dfc4616d DC |
1814 | if (!glock_workqueue) |
1815 | return -ENOMEM; | |
d2115778 | 1816 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
58a69cb4 | 1817 | WQ_MEM_RECLAIM | WQ_FREEZABLE, |
d2115778 | 1818 | 0); |
dfc4616d | 1819 | if (!gfs2_delete_workqueue) { |
b94a170e | 1820 | destroy_workqueue(glock_workqueue); |
dfc4616d | 1821 | return -ENOMEM; |
b94a170e | 1822 | } |
97cc1025 SW |
1823 | |
1824 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1825 | |
85d1da67 SW |
1826 | return 0; |
1827 | } | |
1828 | ||
8fbbfd21 SW |
1829 | void gfs2_glock_exit(void) |
1830 | { | |
97cc1025 | 1831 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1832 | destroy_workqueue(glock_workqueue); |
b94a170e | 1833 | destroy_workqueue(gfs2_delete_workqueue); |
8fbbfd21 SW |
1834 | } |
1835 | ||
bc015cb8 SW |
1836 | static inline struct gfs2_glock *glock_hash_chain(unsigned hash) |
1837 | { | |
1838 | return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]), | |
1839 | struct gfs2_glock, gl_list); | |
1840 | } | |
1841 | ||
1842 | static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl) | |
1843 | { | |
7e32d026 | 1844 | return hlist_bl_entry(rcu_dereference(gl->gl_list.next), |
bc015cb8 SW |
1845 | struct gfs2_glock, gl_list); |
1846 | } | |
1847 | ||
6802e340 | 1848 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1849 | { |
7b08fc62 SW |
1850 | struct gfs2_glock *gl; |
1851 | ||
bc015cb8 SW |
1852 | do { |
1853 | gl = gi->gl; | |
1854 | if (gl) { | |
1855 | gi->gl = glock_hash_next(gl); | |
ba1ddcb6 | 1856 | gi->nhash++; |
bc015cb8 | 1857 | } else { |
ba1ddcb6 SW |
1858 | if (gi->hash >= GFS2_GL_HASH_SIZE) { |
1859 | rcu_read_unlock(); | |
1860 | return 1; | |
1861 | } | |
bc015cb8 | 1862 | gi->gl = glock_hash_chain(gi->hash); |
ba1ddcb6 | 1863 | gi->nhash = 0; |
bc015cb8 SW |
1864 | } |
1865 | while (gi->gl == NULL) { | |
1866 | gi->hash++; | |
1867 | if (gi->hash >= GFS2_GL_HASH_SIZE) { | |
1868 | rcu_read_unlock(); | |
1869 | return 1; | |
1870 | } | |
1871 | gi->gl = glock_hash_chain(gi->hash); | |
ba1ddcb6 | 1872 | gi->nhash = 0; |
bc015cb8 SW |
1873 | } |
1874 | /* Skip entries for other sb and dead entries */ | |
e3c4269d MN |
1875 | } while (gi->sdp != gi->gl->gl_sbd || |
1876 | __lockref_is_dead(&gi->gl->gl_lockref)); | |
a947e033 | 1877 | |
7c52b166 RP |
1878 | return 0; |
1879 | } | |
1880 | ||
6802e340 | 1881 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1882 | { |
6802e340 | 1883 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1884 | loff_t n = *pos; |
1885 | ||
ba1ddcb6 SW |
1886 | if (gi->last_pos <= *pos) |
1887 | n = gi->nhash + (*pos - gi->last_pos); | |
1888 | else | |
1889 | gi->hash = 0; | |
1890 | ||
1891 | gi->nhash = 0; | |
bc015cb8 | 1892 | rcu_read_lock(); |
7c52b166 | 1893 | |
6802e340 | 1894 | do { |
bc015cb8 | 1895 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1896 | return NULL; |
6802e340 | 1897 | } while (n--); |
7c52b166 | 1898 | |
ba1ddcb6 | 1899 | gi->last_pos = *pos; |
6802e340 | 1900 | return gi->gl; |
7c52b166 RP |
1901 | } |
1902 | ||
6802e340 | 1903 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1904 | loff_t *pos) |
1905 | { | |
6802e340 | 1906 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1907 | |
1908 | (*pos)++; | |
ba1ddcb6 | 1909 | gi->last_pos = *pos; |
bc015cb8 | 1910 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1911 | return NULL; |
7c52b166 | 1912 | |
6802e340 | 1913 | return gi->gl; |
7c52b166 RP |
1914 | } |
1915 | ||
6802e340 | 1916 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1917 | { |
6802e340 | 1918 | struct gfs2_glock_iter *gi = seq->private; |
bc015cb8 SW |
1919 | |
1920 | if (gi->gl) | |
1921 | rcu_read_unlock(); | |
1922 | gi->gl = NULL; | |
7c52b166 RP |
1923 | } |
1924 | ||
6802e340 | 1925 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1926 | { |
ac3beb6a SW |
1927 | dump_glock(seq, iter_ptr); |
1928 | return 0; | |
7c52b166 RP |
1929 | } |
1930 | ||
a245769f SW |
1931 | static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos) |
1932 | { | |
1933 | struct gfs2_glock_iter *gi = seq->private; | |
1934 | ||
1935 | gi->hash = *pos; | |
1936 | if (*pos >= GFS2_NR_SBSTATS) | |
1937 | return NULL; | |
1938 | preempt_disable(); | |
1939 | return SEQ_START_TOKEN; | |
1940 | } | |
1941 | ||
1942 | static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr, | |
1943 | loff_t *pos) | |
1944 | { | |
1945 | struct gfs2_glock_iter *gi = seq->private; | |
1946 | (*pos)++; | |
1947 | gi->hash++; | |
1948 | if (gi->hash >= GFS2_NR_SBSTATS) { | |
1949 | preempt_enable(); | |
1950 | return NULL; | |
1951 | } | |
1952 | return SEQ_START_TOKEN; | |
1953 | } | |
1954 | ||
1955 | static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr) | |
1956 | { | |
1957 | preempt_enable(); | |
1958 | } | |
1959 | ||
4ef29002 | 1960 | static const struct seq_operations gfs2_glock_seq_ops = { |
7c52b166 RP |
1961 | .start = gfs2_glock_seq_start, |
1962 | .next = gfs2_glock_seq_next, | |
1963 | .stop = gfs2_glock_seq_stop, | |
1964 | .show = gfs2_glock_seq_show, | |
1965 | }; | |
1966 | ||
a245769f SW |
1967 | static const struct seq_operations gfs2_glstats_seq_ops = { |
1968 | .start = gfs2_glock_seq_start, | |
1969 | .next = gfs2_glock_seq_next, | |
1970 | .stop = gfs2_glock_seq_stop, | |
1971 | .show = gfs2_glstats_seq_show, | |
1972 | }; | |
1973 | ||
1974 | static const struct seq_operations gfs2_sbstats_seq_ops = { | |
1975 | .start = gfs2_sbstats_seq_start, | |
1976 | .next = gfs2_sbstats_seq_next, | |
1977 | .stop = gfs2_sbstats_seq_stop, | |
1978 | .show = gfs2_sbstats_seq_show, | |
1979 | }; | |
1980 | ||
0fe2f1e9 SW |
1981 | #define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL) |
1982 | ||
a245769f | 1983 | static int gfs2_glocks_open(struct inode *inode, struct file *file) |
7c52b166 | 1984 | { |
6802e340 SW |
1985 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
1986 | sizeof(struct gfs2_glock_iter)); | |
1987 | if (ret == 0) { | |
1988 | struct seq_file *seq = file->private_data; | |
1989 | struct gfs2_glock_iter *gi = seq->private; | |
1990 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 1991 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 1992 | if (seq->buf) |
0fe2f1e9 | 1993 | seq->size = GFS2_SEQ_GOODSIZE; |
6802e340 SW |
1994 | } |
1995 | return ret; | |
7c52b166 RP |
1996 | } |
1997 | ||
a245769f SW |
1998 | static int gfs2_glstats_open(struct inode *inode, struct file *file) |
1999 | { | |
2000 | int ret = seq_open_private(file, &gfs2_glstats_seq_ops, | |
2001 | sizeof(struct gfs2_glock_iter)); | |
2002 | if (ret == 0) { | |
2003 | struct seq_file *seq = file->private_data; | |
2004 | struct gfs2_glock_iter *gi = seq->private; | |
2005 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 2006 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 2007 | if (seq->buf) |
0fe2f1e9 | 2008 | seq->size = GFS2_SEQ_GOODSIZE; |
a245769f SW |
2009 | } |
2010 | return ret; | |
2011 | } | |
2012 | ||
2013 | static int gfs2_sbstats_open(struct inode *inode, struct file *file) | |
2014 | { | |
2015 | int ret = seq_open_private(file, &gfs2_sbstats_seq_ops, | |
2016 | sizeof(struct gfs2_glock_iter)); | |
2017 | if (ret == 0) { | |
2018 | struct seq_file *seq = file->private_data; | |
2019 | struct gfs2_glock_iter *gi = seq->private; | |
2020 | gi->sdp = inode->i_private; | |
2021 | } | |
2022 | return ret; | |
2023 | } | |
2024 | ||
2025 | static const struct file_operations gfs2_glocks_fops = { | |
2026 | .owner = THIS_MODULE, | |
2027 | .open = gfs2_glocks_open, | |
2028 | .read = seq_read, | |
2029 | .llseek = seq_lseek, | |
2030 | .release = seq_release_private, | |
2031 | }; | |
2032 | ||
2033 | static const struct file_operations gfs2_glstats_fops = { | |
7c52b166 | 2034 | .owner = THIS_MODULE, |
a245769f SW |
2035 | .open = gfs2_glstats_open, |
2036 | .read = seq_read, | |
2037 | .llseek = seq_lseek, | |
2038 | .release = seq_release_private, | |
2039 | }; | |
2040 | ||
2041 | static const struct file_operations gfs2_sbstats_fops = { | |
2042 | .owner = THIS_MODULE, | |
2043 | .open = gfs2_sbstats_open, | |
7c52b166 RP |
2044 | .read = seq_read, |
2045 | .llseek = seq_lseek, | |
6802e340 | 2046 | .release = seq_release_private, |
7c52b166 RP |
2047 | }; |
2048 | ||
2049 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
2050 | { | |
7b4ddfa7 CS |
2051 | struct dentry *dent; |
2052 | ||
2053 | dent = debugfs_create_dir(sdp->sd_table_name, gfs2_root); | |
2054 | if (IS_ERR_OR_NULL(dent)) | |
2055 | goto fail; | |
2056 | sdp->debugfs_dir = dent; | |
2057 | ||
2058 | dent = debugfs_create_file("glocks", | |
2059 | S_IFREG | S_IRUGO, | |
2060 | sdp->debugfs_dir, sdp, | |
2061 | &gfs2_glocks_fops); | |
2062 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2063 | goto fail; |
7b4ddfa7 | 2064 | sdp->debugfs_dentry_glocks = dent; |
a245769f | 2065 | |
7b4ddfa7 CS |
2066 | dent = debugfs_create_file("glstats", |
2067 | S_IFREG | S_IRUGO, | |
2068 | sdp->debugfs_dir, sdp, | |
2069 | &gfs2_glstats_fops); | |
2070 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2071 | goto fail; |
7b4ddfa7 | 2072 | sdp->debugfs_dentry_glstats = dent; |
a245769f | 2073 | |
7b4ddfa7 CS |
2074 | dent = debugfs_create_file("sbstats", |
2075 | S_IFREG | S_IRUGO, | |
2076 | sdp->debugfs_dir, sdp, | |
2077 | &gfs2_sbstats_fops); | |
2078 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2079 | goto fail; |
7b4ddfa7 | 2080 | sdp->debugfs_dentry_sbstats = dent; |
7c52b166 RP |
2081 | |
2082 | return 0; | |
a245769f SW |
2083 | fail: |
2084 | gfs2_delete_debugfs_file(sdp); | |
7b4ddfa7 | 2085 | return dent ? PTR_ERR(dent) : -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); | |
7b4ddfa7 CS |
2111 | if (IS_ERR(gfs2_root)) |
2112 | return PTR_ERR(gfs2_root); | |
7c52b166 RP |
2113 | return gfs2_root ? 0 : -ENOMEM; |
2114 | } | |
2115 | ||
2116 | void gfs2_unregister_debugfs(void) | |
2117 | { | |
2118 | debugfs_remove(gfs2_root); | |
5f882096 | 2119 | gfs2_root = NULL; |
7c52b166 | 2120 | } |