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 | 121 | { |
15562c43 | 122 | struct gfs2_sbd *sdp = gl->gl_name.ln_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 | { |
15562c43 | 195 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
bc015cb8 | 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, |
d6a53727 | 223 | const struct lm_lockname *name) |
b3b94faa DT |
224 | { |
225 | struct gfs2_glock *gl; | |
bc015cb8 | 226 | struct hlist_bl_node *h; |
b3b94faa | 227 | |
bc015cb8 | 228 | hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) { |
b3b94faa DT |
229 | if (!lm_name_equal(&gl->gl_name, name)) |
230 | continue; | |
e66cf161 | 231 | if (lockref_get_not_dead(&gl->gl_lockref)) |
bc015cb8 | 232 | return gl; |
b3b94faa DT |
233 | } |
234 | ||
235 | return NULL; | |
236 | } | |
237 | ||
6802e340 SW |
238 | /** |
239 | * may_grant - check if its ok to grant a new lock | |
240 | * @gl: The glock | |
241 | * @gh: The lock request which we wish to grant | |
242 | * | |
243 | * Returns: true if its ok to grant the lock | |
244 | */ | |
245 | ||
246 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) | |
247 | { | |
248 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); | |
249 | if ((gh->gh_state == LM_ST_EXCLUSIVE || | |
250 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) | |
251 | return 0; | |
252 | if (gl->gl_state == gh->gh_state) | |
253 | return 1; | |
254 | if (gh->gh_flags & GL_EXACT) | |
255 | return 0; | |
209806ab SW |
256 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
257 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) | |
258 | return 1; | |
259 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) | |
260 | return 1; | |
261 | } | |
6802e340 SW |
262 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
263 | return 1; | |
264 | return 0; | |
265 | } | |
266 | ||
267 | static void gfs2_holder_wake(struct gfs2_holder *gh) | |
268 | { | |
269 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
4e857c58 | 270 | smp_mb__after_atomic(); |
6802e340 SW |
271 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); |
272 | } | |
273 | ||
d5341a92 SW |
274 | /** |
275 | * do_error - Something unexpected has happened during a lock request | |
276 | * | |
277 | */ | |
278 | ||
279 | static inline void do_error(struct gfs2_glock *gl, const int ret) | |
280 | { | |
281 | struct gfs2_holder *gh, *tmp; | |
282 | ||
283 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
284 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
285 | continue; | |
286 | if (ret & LM_OUT_ERROR) | |
287 | gh->gh_error = -EIO; | |
288 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) | |
289 | gh->gh_error = GLR_TRYFAILED; | |
290 | else | |
291 | continue; | |
292 | list_del_init(&gh->gh_list); | |
293 | trace_gfs2_glock_queue(gh, 0); | |
294 | gfs2_holder_wake(gh); | |
295 | } | |
296 | } | |
297 | ||
6802e340 SW |
298 | /** |
299 | * do_promote - promote as many requests as possible on the current queue | |
300 | * @gl: The glock | |
301 | * | |
813e0c46 SW |
302 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
303 | * if a type specific operation is underway. | |
6802e340 SW |
304 | */ |
305 | ||
306 | static int do_promote(struct gfs2_glock *gl) | |
55ba474d HH |
307 | __releases(&gl->gl_spin) |
308 | __acquires(&gl->gl_spin) | |
6802e340 SW |
309 | { |
310 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
311 | struct gfs2_holder *gh, *tmp; | |
312 | int ret; | |
313 | ||
314 | restart: | |
315 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
316 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
317 | continue; | |
318 | if (may_grant(gl, gh)) { | |
319 | if (gh->gh_list.prev == &gl->gl_holders && | |
320 | glops->go_lock) { | |
321 | spin_unlock(&gl->gl_spin); | |
322 | /* FIXME: eliminate this eventually */ | |
323 | ret = glops->go_lock(gh); | |
324 | spin_lock(&gl->gl_spin); | |
325 | if (ret) { | |
813e0c46 SW |
326 | if (ret == 1) |
327 | return 2; | |
6802e340 SW |
328 | gh->gh_error = ret; |
329 | list_del_init(&gh->gh_list); | |
63997775 | 330 | trace_gfs2_glock_queue(gh, 0); |
6802e340 SW |
331 | gfs2_holder_wake(gh); |
332 | goto restart; | |
333 | } | |
334 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 335 | trace_gfs2_promote(gh, 1); |
6802e340 SW |
336 | gfs2_holder_wake(gh); |
337 | goto restart; | |
338 | } | |
339 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 340 | trace_gfs2_promote(gh, 0); |
6802e340 SW |
341 | gfs2_holder_wake(gh); |
342 | continue; | |
343 | } | |
344 | if (gh->gh_list.prev == &gl->gl_holders) | |
345 | return 1; | |
d5341a92 | 346 | do_error(gl, 0); |
6802e340 SW |
347 | break; |
348 | } | |
349 | return 0; | |
350 | } | |
351 | ||
6802e340 SW |
352 | /** |
353 | * find_first_waiter - find the first gh that's waiting for the glock | |
354 | * @gl: the glock | |
355 | */ | |
356 | ||
357 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) | |
358 | { | |
359 | struct gfs2_holder *gh; | |
360 | ||
361 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
362 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
363 | return gh; | |
364 | } | |
365 | return NULL; | |
366 | } | |
367 | ||
368 | /** | |
369 | * state_change - record that the glock is now in a different state | |
370 | * @gl: the glock | |
371 | * @new_state the new state | |
372 | * | |
373 | */ | |
374 | ||
375 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
376 | { | |
377 | int held1, held2; | |
378 | ||
379 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
380 | held2 = (new_state != LM_ST_UNLOCKED); | |
381 | ||
382 | if (held1 != held2) { | |
e66cf161 | 383 | GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); |
6802e340 | 384 | if (held2) |
e66cf161 | 385 | gl->gl_lockref.count++; |
6802e340 | 386 | else |
e66cf161 | 387 | gl->gl_lockref.count--; |
6802e340 | 388 | } |
7b5e3d5f SW |
389 | if (held1 && held2 && list_empty(&gl->gl_holders)) |
390 | clear_bit(GLF_QUEUED, &gl->gl_flags); | |
6802e340 | 391 | |
7cf8dcd3 BP |
392 | if (new_state != gl->gl_target) |
393 | /* shorten our minimum hold time */ | |
394 | gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR, | |
395 | GL_GLOCK_MIN_HOLD); | |
6802e340 SW |
396 | gl->gl_state = new_state; |
397 | gl->gl_tchange = jiffies; | |
398 | } | |
399 | ||
400 | static void gfs2_demote_wake(struct gfs2_glock *gl) | |
401 | { | |
402 | gl->gl_demote_state = LM_ST_EXCLUSIVE; | |
403 | clear_bit(GLF_DEMOTE, &gl->gl_flags); | |
4e857c58 | 404 | smp_mb__after_atomic(); |
6802e340 SW |
405 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); |
406 | } | |
407 | ||
408 | /** | |
409 | * finish_xmote - The DLM has replied to one of our lock requests | |
410 | * @gl: The glock | |
411 | * @ret: The status from the DLM | |
412 | * | |
413 | */ | |
414 | ||
415 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) | |
416 | { | |
417 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
418 | struct gfs2_holder *gh; | |
419 | unsigned state = ret & LM_OUT_ST_MASK; | |
813e0c46 | 420 | int rv; |
6802e340 SW |
421 | |
422 | spin_lock(&gl->gl_spin); | |
63997775 | 423 | trace_gfs2_glock_state_change(gl, state); |
6802e340 SW |
424 | state_change(gl, state); |
425 | gh = find_first_waiter(gl); | |
426 | ||
427 | /* Demote to UN request arrived during demote to SH or DF */ | |
428 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && | |
429 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) | |
430 | gl->gl_target = LM_ST_UNLOCKED; | |
431 | ||
432 | /* Check for state != intended state */ | |
433 | if (unlikely(state != gl->gl_target)) { | |
434 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { | |
435 | /* move to back of queue and try next entry */ | |
436 | if (ret & LM_OUT_CANCELED) { | |
437 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) | |
438 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
439 | gh = find_first_waiter(gl); | |
440 | gl->gl_target = gh->gh_state; | |
441 | goto retry; | |
442 | } | |
443 | /* Some error or failed "try lock" - report it */ | |
444 | if ((ret & LM_OUT_ERROR) || | |
445 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
446 | gl->gl_target = gl->gl_state; | |
447 | do_error(gl, ret); | |
448 | goto out; | |
449 | } | |
450 | } | |
451 | switch(state) { | |
452 | /* Unlocked due to conversion deadlock, try again */ | |
453 | case LM_ST_UNLOCKED: | |
454 | retry: | |
455 | do_xmote(gl, gh, gl->gl_target); | |
456 | break; | |
457 | /* Conversion fails, unlock and try again */ | |
458 | case LM_ST_SHARED: | |
459 | case LM_ST_DEFERRED: | |
460 | do_xmote(gl, gh, LM_ST_UNLOCKED); | |
461 | break; | |
462 | default: /* Everything else */ | |
d77d1b58 | 463 | pr_err("wanted %u got %u\n", gl->gl_target, state); |
6802e340 SW |
464 | GLOCK_BUG_ON(gl, 1); |
465 | } | |
466 | spin_unlock(&gl->gl_spin); | |
6802e340 SW |
467 | return; |
468 | } | |
469 | ||
470 | /* Fast path - we got what we asked for */ | |
471 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) | |
472 | gfs2_demote_wake(gl); | |
473 | if (state != LM_ST_UNLOCKED) { | |
474 | if (glops->go_xmote_bh) { | |
6802e340 SW |
475 | spin_unlock(&gl->gl_spin); |
476 | rv = glops->go_xmote_bh(gl, gh); | |
6802e340 SW |
477 | spin_lock(&gl->gl_spin); |
478 | if (rv) { | |
479 | do_error(gl, rv); | |
480 | goto out; | |
481 | } | |
482 | } | |
813e0c46 SW |
483 | rv = do_promote(gl); |
484 | if (rv == 2) | |
485 | goto out_locked; | |
6802e340 SW |
486 | } |
487 | out: | |
488 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
813e0c46 | 489 | out_locked: |
6802e340 | 490 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
491 | } |
492 | ||
6802e340 SW |
493 | /** |
494 | * do_xmote - Calls the DLM to change the state of a lock | |
495 | * @gl: The lock state | |
496 | * @gh: The holder (only for promotes) | |
497 | * @target: The target lock state | |
498 | * | |
499 | */ | |
500 | ||
501 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) | |
55ba474d HH |
502 | __releases(&gl->gl_spin) |
503 | __acquires(&gl->gl_spin) | |
6802e340 SW |
504 | { |
505 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
15562c43 | 506 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
6802e340 SW |
507 | unsigned int lck_flags = gh ? gh->gh_flags : 0; |
508 | int ret; | |
509 | ||
510 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | | |
511 | LM_FLAG_PRIORITY); | |
921169ca SW |
512 | GLOCK_BUG_ON(gl, gl->gl_state == target); |
513 | GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target); | |
6802e340 SW |
514 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && |
515 | glops->go_inval) { | |
516 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
517 | do_error(gl, 0); /* Fail queued try locks */ | |
518 | } | |
47a25380 | 519 | gl->gl_req = target; |
a245769f SW |
520 | set_bit(GLF_BLOCKING, &gl->gl_flags); |
521 | if ((gl->gl_req == LM_ST_UNLOCKED) || | |
522 | (gl->gl_state == LM_ST_EXCLUSIVE) || | |
523 | (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB))) | |
524 | clear_bit(GLF_BLOCKING, &gl->gl_flags); | |
6802e340 | 525 | spin_unlock(&gl->gl_spin); |
06dfc306 BP |
526 | if (glops->go_sync) |
527 | glops->go_sync(gl); | |
6802e340 SW |
528 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
529 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); | |
530 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
531 | ||
532 | gfs2_glock_hold(gl); | |
921169ca SW |
533 | if (sdp->sd_lockstruct.ls_ops->lm_lock) { |
534 | /* lock_dlm */ | |
535 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags); | |
dba2d70c | 536 | if (ret) { |
d77d1b58 | 537 | pr_err("lm_lock ret %d\n", ret); |
dba2d70c DT |
538 | GLOCK_BUG_ON(gl, 1); |
539 | } | |
921169ca SW |
540 | } else { /* lock_nolock */ |
541 | finish_xmote(gl, target); | |
6802e340 SW |
542 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
543 | gfs2_glock_put(gl); | |
6802e340 | 544 | } |
921169ca | 545 | |
6802e340 SW |
546 | spin_lock(&gl->gl_spin); |
547 | } | |
548 | ||
549 | /** | |
550 | * find_first_holder - find the first "holder" gh | |
551 | * @gl: the glock | |
552 | */ | |
553 | ||
554 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) | |
555 | { | |
556 | struct gfs2_holder *gh; | |
557 | ||
558 | if (!list_empty(&gl->gl_holders)) { | |
559 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
560 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
561 | return gh; | |
562 | } | |
563 | return NULL; | |
564 | } | |
565 | ||
566 | /** | |
567 | * run_queue - do all outstanding tasks related to a glock | |
568 | * @gl: The glock in question | |
569 | * @nonblock: True if we must not block in run_queue | |
570 | * | |
571 | */ | |
572 | ||
573 | static void run_queue(struct gfs2_glock *gl, const int nonblock) | |
55ba474d HH |
574 | __releases(&gl->gl_spin) |
575 | __acquires(&gl->gl_spin) | |
6802e340 SW |
576 | { |
577 | struct gfs2_holder *gh = NULL; | |
813e0c46 | 578 | int ret; |
6802e340 SW |
579 | |
580 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
581 | return; | |
582 | ||
583 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); | |
584 | ||
585 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && | |
586 | gl->gl_demote_state != gl->gl_state) { | |
587 | if (find_first_holder(gl)) | |
d8348de0 | 588 | goto out_unlock; |
6802e340 SW |
589 | if (nonblock) |
590 | goto out_sched; | |
591 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); | |
265d529c | 592 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
6802e340 SW |
593 | gl->gl_target = gl->gl_demote_state; |
594 | } else { | |
595 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
596 | gfs2_demote_wake(gl); | |
813e0c46 SW |
597 | ret = do_promote(gl); |
598 | if (ret == 0) | |
d8348de0 | 599 | goto out_unlock; |
813e0c46 | 600 | if (ret == 2) |
a228df63 | 601 | goto out; |
6802e340 SW |
602 | gh = find_first_waiter(gl); |
603 | gl->gl_target = gh->gh_state; | |
604 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
605 | do_error(gl, 0); /* Fail queued try locks */ | |
606 | } | |
607 | do_xmote(gl, gh, gl->gl_target); | |
a228df63 | 608 | out: |
6802e340 SW |
609 | return; |
610 | ||
611 | out_sched: | |
7e71c55e | 612 | clear_bit(GLF_LOCK, &gl->gl_flags); |
4e857c58 | 613 | smp_mb__after_atomic(); |
e66cf161 | 614 | gl->gl_lockref.count++; |
6802e340 | 615 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 616 | gl->gl_lockref.count--; |
7e71c55e SW |
617 | return; |
618 | ||
d8348de0 | 619 | out_unlock: |
6802e340 | 620 | clear_bit(GLF_LOCK, &gl->gl_flags); |
4e857c58 | 621 | smp_mb__after_atomic(); |
7e71c55e | 622 | return; |
6802e340 SW |
623 | } |
624 | ||
b94a170e BM |
625 | static void delete_work_func(struct work_struct *work) |
626 | { | |
627 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete); | |
15562c43 | 628 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
044b9414 | 629 | struct gfs2_inode *ip; |
b94a170e | 630 | struct inode *inode; |
044b9414 SW |
631 | u64 no_addr = gl->gl_name.ln_number; |
632 | ||
633 | ip = gl->gl_object; | |
634 | /* Note: Unsafe to dereference ip as we don't hold right refs/locks */ | |
b94a170e | 635 | |
b94a170e | 636 | if (ip) |
4667a0ec | 637 | inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1); |
044b9414 SW |
638 | else |
639 | inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED); | |
640 | if (inode && !IS_ERR(inode)) { | |
641 | d_prune_aliases(inode); | |
642 | iput(inode); | |
b94a170e BM |
643 | } |
644 | gfs2_glock_put(gl); | |
645 | } | |
646 | ||
c4f68a13 BM |
647 | static void glock_work_func(struct work_struct *work) |
648 | { | |
6802e340 | 649 | unsigned long delay = 0; |
c4f68a13 | 650 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
26bb7505 | 651 | int drop_ref = 0; |
c4f68a13 | 652 | |
26bb7505 | 653 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) { |
6802e340 | 654 | finish_xmote(gl, gl->gl_reply); |
26bb7505 SW |
655 | drop_ref = 1; |
656 | } | |
c4f68a13 | 657 | spin_lock(&gl->gl_spin); |
f90e5b5b | 658 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
265d529c SW |
659 | gl->gl_state != LM_ST_UNLOCKED && |
660 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { | |
6802e340 | 661 | unsigned long holdtime, now = jiffies; |
f90e5b5b | 662 | |
7cf8dcd3 | 663 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
6802e340 SW |
664 | if (time_before(now, holdtime)) |
665 | delay = holdtime - now; | |
f90e5b5b BP |
666 | |
667 | if (!delay) { | |
668 | clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags); | |
669 | set_bit(GLF_DEMOTE, &gl->gl_flags); | |
670 | } | |
6802e340 SW |
671 | } |
672 | run_queue(gl, 0); | |
c4f68a13 | 673 | spin_unlock(&gl->gl_spin); |
7cf8dcd3 | 674 | if (!delay) |
6802e340 | 675 | gfs2_glock_put(gl); |
7cf8dcd3 BP |
676 | else { |
677 | if (gl->gl_name.ln_type != LM_TYPE_INODE) | |
678 | delay = 0; | |
679 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
680 | gfs2_glock_put(gl); | |
681 | } | |
26bb7505 SW |
682 | if (drop_ref) |
683 | gfs2_glock_put(gl); | |
c4f68a13 BM |
684 | } |
685 | ||
b3b94faa DT |
686 | /** |
687 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
688 | * @sdp: The GFS2 superblock | |
689 | * @number: the lock number | |
690 | * @glops: The glock_operations to use | |
691 | * @create: If 0, don't create the glock if it doesn't exist | |
692 | * @glp: the glock is returned here | |
693 | * | |
694 | * This does not lock a glock, just finds/creates structures for one. | |
695 | * | |
696 | * Returns: errno | |
697 | */ | |
698 | ||
cd915493 | 699 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 | 700 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
701 | struct gfs2_glock **glp) |
702 | { | |
009d8518 | 703 | struct super_block *s = sdp->sd_vfs; |
15562c43 BP |
704 | struct lm_lockname name = { .ln_number = number, |
705 | .ln_type = glops->go_type, | |
706 | .ln_sbd = sdp }; | |
b3b94faa | 707 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 708 | unsigned int hash = gl_hash(sdp, &name); |
009d8518 | 709 | struct address_space *mapping; |
bc015cb8 | 710 | struct kmem_cache *cachep; |
b3b94faa | 711 | |
bc015cb8 | 712 | rcu_read_lock(); |
15562c43 | 713 | gl = search_bucket(hash, &name); |
bc015cb8 | 714 | rcu_read_unlock(); |
b3b94faa | 715 | |
64d576ba SW |
716 | *glp = gl; |
717 | if (gl) | |
b3b94faa | 718 | return 0; |
64d576ba SW |
719 | if (!create) |
720 | return -ENOENT; | |
b3b94faa | 721 | |
009d8518 | 722 | if (glops->go_flags & GLOF_ASPACE) |
bc015cb8 | 723 | cachep = gfs2_glock_aspace_cachep; |
009d8518 | 724 | else |
bc015cb8 | 725 | cachep = gfs2_glock_cachep; |
fe0bbd29 | 726 | gl = kmem_cache_alloc(cachep, GFP_NOFS); |
b3b94faa DT |
727 | if (!gl) |
728 | return -ENOMEM; | |
729 | ||
dba2d70c | 730 | memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); |
dba2d70c DT |
731 | |
732 | if (glops->go_flags & GLOF_LVB) { | |
fe0bbd29 | 733 | gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_NOFS); |
4e2f8849 | 734 | if (!gl->gl_lksb.sb_lvbptr) { |
dba2d70c DT |
735 | kmem_cache_free(cachep, gl); |
736 | return -ENOMEM; | |
737 | } | |
dba2d70c DT |
738 | } |
739 | ||
8f05228e | 740 | atomic_inc(&sdp->sd_glock_disposal); |
ec45d9f5 | 741 | gl->gl_flags = 0; |
b3b94faa | 742 | gl->gl_name = name; |
e66cf161 | 743 | gl->gl_lockref.count = 1; |
b3b94faa | 744 | gl->gl_state = LM_ST_UNLOCKED; |
6802e340 | 745 | gl->gl_target = LM_ST_UNLOCKED; |
c4f68a13 | 746 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
37b2fa6a | 747 | gl->gl_hash = hash; |
b3b94faa | 748 | gl->gl_ops = glops; |
a245769f SW |
749 | gl->gl_dstamp = ktime_set(0, 0); |
750 | preempt_disable(); | |
751 | /* We use the global stats to estimate the initial per-glock stats */ | |
752 | gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type]; | |
753 | preempt_enable(); | |
754 | gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0; | |
755 | gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0; | |
c4f68a13 | 756 | gl->gl_tchange = jiffies; |
ec45d9f5 | 757 | gl->gl_object = NULL; |
7cf8dcd3 | 758 | gl->gl_hold_time = GL_GLOCK_DFT_HOLD; |
c4f68a13 | 759 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
b94a170e | 760 | INIT_WORK(&gl->gl_delete, delete_work_func); |
b3b94faa | 761 | |
009d8518 SW |
762 | mapping = gfs2_glock2aspace(gl); |
763 | if (mapping) { | |
764 | mapping->a_ops = &gfs2_meta_aops; | |
765 | mapping->host = s->s_bdev->bd_inode; | |
766 | mapping->flags = 0; | |
767 | mapping_set_gfp_mask(mapping, GFP_NOFS); | |
252aa6f5 | 768 | mapping->private_data = NULL; |
009d8518 | 769 | mapping->writeback_index = 0; |
b3b94faa DT |
770 | } |
771 | ||
bc015cb8 | 772 | spin_lock_bucket(hash); |
15562c43 | 773 | tmp = search_bucket(hash, &name); |
b3b94faa | 774 | if (tmp) { |
bc015cb8 | 775 | spin_unlock_bucket(hash); |
4e2f8849 | 776 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 777 | kmem_cache_free(cachep, gl); |
fc0e38da | 778 | atomic_dec(&sdp->sd_glock_disposal); |
b3b94faa DT |
779 | gl = tmp; |
780 | } else { | |
bc015cb8 SW |
781 | hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]); |
782 | spin_unlock_bucket(hash); | |
b3b94faa DT |
783 | } |
784 | ||
785 | *glp = gl; | |
786 | ||
787 | return 0; | |
b3b94faa DT |
788 | } |
789 | ||
790 | /** | |
791 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
792 | * @gl: the glock | |
793 | * @state: the state we're requesting | |
794 | * @flags: the modifier flags | |
795 | * @gh: the holder structure | |
796 | * | |
797 | */ | |
798 | ||
190562bd | 799 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
800 | struct gfs2_holder *gh) |
801 | { | |
802 | INIT_LIST_HEAD(&gh->gh_list); | |
803 | gh->gh_gl = gl; | |
d29c0afe | 804 | gh->gh_ip = _RET_IP_; |
b1e058da | 805 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
806 | gh->gh_state = state; |
807 | gh->gh_flags = flags; | |
808 | gh->gh_error = 0; | |
809 | gh->gh_iflags = 0; | |
b3b94faa DT |
810 | gfs2_glock_hold(gl); |
811 | } | |
812 | ||
813 | /** | |
814 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
815 | * @state: the state we're requesting | |
816 | * @flags: the modifier flags | |
817 | * @gh: the holder structure | |
818 | * | |
819 | * Don't mess with the glock. | |
820 | * | |
821 | */ | |
822 | ||
190562bd | 823 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
824 | { |
825 | gh->gh_state = state; | |
579b78a4 | 826 | gh->gh_flags = flags; |
3b8249f6 | 827 | gh->gh_iflags = 0; |
d29c0afe | 828 | gh->gh_ip = _RET_IP_; |
30badc95 | 829 | put_pid(gh->gh_owner_pid); |
1a0eae88 | 830 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
831 | } |
832 | ||
833 | /** | |
834 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
835 | * @gh: the holder structure | |
836 | * | |
837 | */ | |
838 | ||
839 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
840 | { | |
b1e058da | 841 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
842 | gfs2_glock_put(gh->gh_gl); |
843 | gh->gh_gl = NULL; | |
d0dc80db | 844 | gh->gh_ip = 0; |
b3b94faa DT |
845 | } |
846 | ||
07a79049 BP |
847 | /** |
848 | * gfs2_glock_wait - wait on a glock acquisition | |
849 | * @gh: the glock holder | |
850 | * | |
851 | * Returns: 0 on success | |
852 | */ | |
853 | ||
854 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
da755fdb | 855 | { |
7cf8dcd3 BP |
856 | unsigned long time1 = jiffies; |
857 | ||
6802e340 | 858 | might_sleep(); |
74316201 | 859 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE); |
7cf8dcd3 BP |
860 | if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */ |
861 | /* Lengthen the minimum hold time. */ | |
862 | gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time + | |
863 | GL_GLOCK_HOLD_INCR, | |
864 | GL_GLOCK_MAX_HOLD); | |
07a79049 | 865 | return gh->gh_error; |
da755fdb SW |
866 | } |
867 | ||
b3b94faa | 868 | /** |
6802e340 SW |
869 | * handle_callback - process a demote request |
870 | * @gl: the glock | |
871 | * @state: the state the caller wants us to change to | |
b3b94faa | 872 | * |
6802e340 SW |
873 | * There are only two requests that we are going to see in actual |
874 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
875 | */ |
876 | ||
6802e340 | 877 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
81ffbf65 | 878 | unsigned long delay, bool remote) |
b3b94faa | 879 | { |
6802e340 | 880 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 881 | |
6802e340 SW |
882 | set_bit(bit, &gl->gl_flags); |
883 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
884 | gl->gl_demote_state = state; | |
885 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
886 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
887 | gl->gl_demote_state != state) { | |
888 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 889 | } |
b94a170e | 890 | if (gl->gl_ops->go_callback) |
81ffbf65 | 891 | gl->gl_ops->go_callback(gl, remote); |
7bd8b2eb | 892 | trace_gfs2_demote_rq(gl, remote); |
b3b94faa DT |
893 | } |
894 | ||
6802e340 | 895 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 | 896 | { |
5e69069c | 897 | struct va_format vaf; |
7c52b166 RP |
898 | va_list args; |
899 | ||
900 | va_start(args, fmt); | |
5e69069c | 901 | |
6802e340 | 902 | if (seq) { |
1bb49303 | 903 | seq_vprintf(seq, fmt, args); |
6802e340 | 904 | } else { |
5e69069c JP |
905 | vaf.fmt = fmt; |
906 | vaf.va = &args; | |
907 | ||
d77d1b58 | 908 | pr_err("%pV", &vaf); |
6802e340 | 909 | } |
5e69069c | 910 | |
7c52b166 RP |
911 | va_end(args); |
912 | } | |
913 | ||
b3b94faa DT |
914 | /** |
915 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
916 | * @gh: the holder structure to add | |
917 | * | |
6802e340 SW |
918 | * Eventually we should move the recursive locking trap to a |
919 | * debugging option or something like that. This is the fast | |
920 | * path and needs to have the minimum number of distractions. | |
921 | * | |
b3b94faa DT |
922 | */ |
923 | ||
6802e340 | 924 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
925 | __releases(&gl->gl_spin) |
926 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
927 | { |
928 | struct gfs2_glock *gl = gh->gh_gl; | |
15562c43 | 929 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
6802e340 SW |
930 | struct list_head *insert_pt = NULL; |
931 | struct gfs2_holder *gh2; | |
e5dc76b9 | 932 | int try_futile = 0; |
b3b94faa | 933 | |
b1e058da | 934 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
935 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
936 | BUG(); | |
190562bd | 937 | |
6802e340 SW |
938 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
939 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
e5dc76b9 | 940 | try_futile = !may_grant(gl, gh); |
6802e340 SW |
941 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
942 | goto fail; | |
943 | } | |
944 | ||
945 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
946 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
947 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
948 | goto trap_recursive; | |
e5dc76b9 BP |
949 | if (try_futile && |
950 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
6802e340 SW |
951 | fail: |
952 | gh->gh_error = GLR_TRYFAILED; | |
953 | gfs2_holder_wake(gh); | |
954 | return; | |
b4c20166 | 955 | } |
6802e340 SW |
956 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
957 | continue; | |
958 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
959 | insert_pt = &gh2->gh_list; | |
960 | } | |
7b5e3d5f | 961 | set_bit(GLF_QUEUED, &gl->gl_flags); |
edae38a6 | 962 | trace_gfs2_glock_queue(gh, 1); |
a245769f SW |
963 | gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT); |
964 | gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT); | |
6802e340 SW |
965 | if (likely(insert_pt == NULL)) { |
966 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
967 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
968 | goto do_cancel; | |
969 | return; | |
970 | } | |
971 | list_add_tail(&gh->gh_list, insert_pt); | |
972 | do_cancel: | |
973 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
974 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
975 | spin_unlock(&gl->gl_spin); | |
048bca22 | 976 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
f057f6cd | 977 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
6802e340 | 978 | spin_lock(&gl->gl_spin); |
b3b94faa | 979 | } |
6802e340 | 980 | return; |
b3b94faa | 981 | |
6802e340 | 982 | trap_recursive: |
fc554ed3 FF |
983 | pr_err("original: %pSR\n", (void *)gh2->gh_ip); |
984 | pr_err("pid: %d\n", pid_nr(gh2->gh_owner_pid)); | |
985 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 986 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); |
fc554ed3 FF |
987 | pr_err("new: %pSR\n", (void *)gh->gh_ip); |
988 | pr_err("pid: %d\n", pid_nr(gh->gh_owner_pid)); | |
989 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 990 | gh->gh_gl->gl_name.ln_type, gh->gh_state); |
8eae1ca0 | 991 | gfs2_dump_glock(NULL, gl); |
6802e340 | 992 | BUG(); |
b3b94faa DT |
993 | } |
994 | ||
995 | /** | |
996 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
997 | * @gh: the holder structure | |
998 | * | |
999 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1000 | * | |
1001 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1002 | */ | |
1003 | ||
1004 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1005 | { | |
1006 | struct gfs2_glock *gl = gh->gh_gl; | |
15562c43 | 1007 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
b3b94faa DT |
1008 | int error = 0; |
1009 | ||
6802e340 | 1010 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1011 | return -EIO; |
b3b94faa | 1012 | |
f42ab085 SW |
1013 | if (test_bit(GLF_LRU, &gl->gl_flags)) |
1014 | gfs2_glock_remove_from_lru(gl); | |
1015 | ||
b3b94faa DT |
1016 | spin_lock(&gl->gl_spin); |
1017 | add_to_queue(gh); | |
01b172b7 BP |
1018 | if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) && |
1019 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) { | |
0809f6ec | 1020 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
01b172b7 BP |
1021 | gl->gl_lockref.count++; |
1022 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1023 | gl->gl_lockref.count--; | |
1024 | } | |
6802e340 | 1025 | run_queue(gl, 1); |
b3b94faa DT |
1026 | spin_unlock(&gl->gl_spin); |
1027 | ||
6802e340 SW |
1028 | if (!(gh->gh_flags & GL_ASYNC)) |
1029 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1030 | |
b3b94faa DT |
1031 | return error; |
1032 | } | |
1033 | ||
1034 | /** | |
1035 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1036 | * @gh: the holder | |
1037 | * | |
1038 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1039 | */ | |
1040 | ||
1041 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1042 | { | |
6802e340 | 1043 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1044 | } |
1045 | ||
1046 | /** | |
1047 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1048 | * @gh: the glock holder | |
1049 | * | |
1050 | */ | |
1051 | ||
1052 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1053 | { | |
1054 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1055 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1056 | unsigned delay = 0; |
6802e340 | 1057 | int fast_path = 0; |
b3b94faa | 1058 | |
6802e340 | 1059 | spin_lock(&gl->gl_spin); |
b3b94faa | 1060 | if (gh->gh_flags & GL_NOCACHE) |
81ffbf65 | 1061 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
b3b94faa | 1062 | |
b3b94faa | 1063 | list_del_init(&gh->gh_list); |
6802e340 | 1064 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1065 | if (glops->go_unlock) { |
6802e340 | 1066 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1067 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1068 | glops->go_unlock(gh); |
3042a2cc | 1069 | spin_lock(&gl->gl_spin); |
6802e340 | 1070 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1071 | } |
6802e340 SW |
1072 | if (list_empty(&gl->gl_holders) && |
1073 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1074 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1075 | fast_path = 1; | |
b3b94faa | 1076 | } |
e7ccaf5f BP |
1077 | if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl) && |
1078 | (glops->go_flags & GLOF_LRU)) | |
4abb6ad9 BP |
1079 | gfs2_glock_add_to_lru(gl); |
1080 | ||
63997775 | 1081 | trace_gfs2_glock_queue(gh, 0); |
b3b94faa | 1082 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1083 | if (likely(fast_path)) |
1084 | return; | |
c4f68a13 BM |
1085 | |
1086 | gfs2_glock_hold(gl); | |
1087 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
7cf8dcd3 BP |
1088 | !test_bit(GLF_DEMOTE, &gl->gl_flags) && |
1089 | gl->gl_name.ln_type == LM_TYPE_INODE) | |
1090 | delay = gl->gl_hold_time; | |
c4f68a13 BM |
1091 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1092 | gfs2_glock_put(gl); | |
b3b94faa DT |
1093 | } |
1094 | ||
d93cfa98 AD |
1095 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1096 | { | |
1097 | struct gfs2_glock *gl = gh->gh_gl; | |
1098 | gfs2_glock_dq(gh); | |
81e1d450 | 1099 | might_sleep(); |
74316201 | 1100 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE); |
d93cfa98 AD |
1101 | } |
1102 | ||
b3b94faa DT |
1103 | /** |
1104 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1105 | * @gh: the holder structure | |
1106 | * | |
1107 | */ | |
1108 | ||
1109 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1110 | { | |
1111 | gfs2_glock_dq(gh); | |
1112 | gfs2_holder_uninit(gh); | |
1113 | } | |
1114 | ||
1115 | /** | |
1116 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1117 | * @sdp: the filesystem | |
1118 | * @number: the lock number | |
1119 | * @glops: the glock operations for the type of glock | |
1120 | * @state: the state to acquire the glock in | |
25985edc | 1121 | * @flags: modifier flags for the acquisition |
b3b94faa DT |
1122 | * @gh: the struct gfs2_holder |
1123 | * | |
1124 | * Returns: errno | |
1125 | */ | |
1126 | ||
cd915493 | 1127 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1128 | const struct gfs2_glock_operations *glops, |
1129 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1130 | { |
1131 | struct gfs2_glock *gl; | |
1132 | int error; | |
1133 | ||
1134 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1135 | if (!error) { | |
1136 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1137 | gfs2_glock_put(gl); | |
1138 | } | |
1139 | ||
1140 | return error; | |
1141 | } | |
1142 | ||
1143 | /** | |
1144 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1145 | * @arg_a: the first structure | |
1146 | * @arg_b: the second structure | |
1147 | * | |
1148 | */ | |
1149 | ||
1150 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1151 | { | |
a5e08a9e SW |
1152 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1153 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1154 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1155 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1156 | |
1157 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1158 | return 1; |
1159 | if (a->ln_number < b->ln_number) | |
1160 | return -1; | |
1c0f4872 | 1161 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1162 | return 0; |
b3b94faa DT |
1163 | } |
1164 | ||
1165 | /** | |
1166 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1167 | * @num_gh: the number of structures | |
1168 | * @ghs: an array of struct gfs2_holder structures | |
1169 | * | |
1170 | * Returns: 0 on success (all glocks acquired), | |
1171 | * errno on failure (no glocks acquired) | |
1172 | */ | |
1173 | ||
1174 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1175 | struct gfs2_holder **p) | |
1176 | { | |
1177 | unsigned int x; | |
1178 | int error = 0; | |
1179 | ||
1180 | for (x = 0; x < num_gh; x++) | |
1181 | p[x] = &ghs[x]; | |
1182 | ||
1183 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1184 | ||
1185 | for (x = 0; x < num_gh; x++) { | |
1186 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1187 | ||
1188 | error = gfs2_glock_nq(p[x]); | |
1189 | if (error) { | |
1190 | while (x--) | |
1191 | gfs2_glock_dq(p[x]); | |
1192 | break; | |
1193 | } | |
1194 | } | |
1195 | ||
1196 | return error; | |
1197 | } | |
1198 | ||
1199 | /** | |
1200 | * gfs2_glock_nq_m - acquire multiple glocks | |
1201 | * @num_gh: the number of structures | |
1202 | * @ghs: an array of struct gfs2_holder structures | |
1203 | * | |
b3b94faa DT |
1204 | * |
1205 | * Returns: 0 on success (all glocks acquired), | |
1206 | * errno on failure (no glocks acquired) | |
1207 | */ | |
1208 | ||
1209 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1210 | { | |
eaf5bd3c SW |
1211 | struct gfs2_holder *tmp[4]; |
1212 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1213 | int error = 0; |
1214 | ||
eaf5bd3c SW |
1215 | switch(num_gh) { |
1216 | case 0: | |
b3b94faa | 1217 | return 0; |
eaf5bd3c | 1218 | case 1: |
b3b94faa DT |
1219 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1220 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1221 | default: |
1222 | if (num_gh <= 4) | |
b3b94faa | 1223 | break; |
eaf5bd3c SW |
1224 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1225 | if (!pph) | |
1226 | return -ENOMEM; | |
b3b94faa DT |
1227 | } |
1228 | ||
eaf5bd3c | 1229 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1230 | |
eaf5bd3c SW |
1231 | if (pph != tmp) |
1232 | kfree(pph); | |
b3b94faa DT |
1233 | |
1234 | return error; | |
1235 | } | |
1236 | ||
1237 | /** | |
1238 | * gfs2_glock_dq_m - release multiple glocks | |
1239 | * @num_gh: the number of structures | |
1240 | * @ghs: an array of struct gfs2_holder structures | |
1241 | * | |
1242 | */ | |
1243 | ||
1244 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1245 | { | |
fa1bbdea BP |
1246 | while (num_gh--) |
1247 | gfs2_glock_dq(&ghs[num_gh]); | |
b3b94faa DT |
1248 | } |
1249 | ||
f057f6cd | 1250 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
da755fdb | 1251 | { |
c4f68a13 BM |
1252 | unsigned long delay = 0; |
1253 | unsigned long holdtime; | |
1254 | unsigned long now = jiffies; | |
b3b94faa | 1255 | |
f057f6cd | 1256 | gfs2_glock_hold(gl); |
7cf8dcd3 BP |
1257 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
1258 | if (test_bit(GLF_QUEUED, &gl->gl_flags) && | |
1259 | gl->gl_name.ln_type == LM_TYPE_INODE) { | |
7b5e3d5f SW |
1260 | if (time_before(now, holdtime)) |
1261 | delay = holdtime - now; | |
1262 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) | |
7cf8dcd3 | 1263 | delay = gl->gl_hold_time; |
7b5e3d5f | 1264 | } |
b3b94faa | 1265 | |
6802e340 | 1266 | spin_lock(&gl->gl_spin); |
81ffbf65 | 1267 | handle_callback(gl, state, delay, true); |
6802e340 | 1268 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1269 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1270 | gfs2_glock_put(gl); | |
b3b94faa DT |
1271 | } |
1272 | ||
0809f6ec SW |
1273 | /** |
1274 | * gfs2_should_freeze - Figure out if glock should be frozen | |
1275 | * @gl: The glock in question | |
1276 | * | |
1277 | * Glocks are not frozen if (a) the result of the dlm operation is | |
1278 | * an error, (b) the locking operation was an unlock operation or | |
1279 | * (c) if there is a "noexp" flagged request anywhere in the queue | |
1280 | * | |
1281 | * Returns: 1 if freezing should occur, 0 otherwise | |
1282 | */ | |
1283 | ||
1284 | static int gfs2_should_freeze(const struct gfs2_glock *gl) | |
1285 | { | |
1286 | const struct gfs2_holder *gh; | |
1287 | ||
1288 | if (gl->gl_reply & ~LM_OUT_ST_MASK) | |
1289 | return 0; | |
1290 | if (gl->gl_target == LM_ST_UNLOCKED) | |
1291 | return 0; | |
1292 | ||
1293 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
1294 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1295 | continue; | |
1296 | if (LM_FLAG_NOEXP & gh->gh_flags) | |
1297 | return 0; | |
1298 | } | |
1299 | ||
1300 | return 1; | |
1301 | } | |
1302 | ||
b3b94faa | 1303 | /** |
f057f6cd SW |
1304 | * gfs2_glock_complete - Callback used by locking |
1305 | * @gl: Pointer to the glock | |
1306 | * @ret: The return value from the dlm | |
b3b94faa | 1307 | * |
47a25380 SW |
1308 | * The gl_reply field is under the gl_spin lock so that it is ok |
1309 | * to use a bitfield shared with other glock state fields. | |
b3b94faa DT |
1310 | */ |
1311 | ||
f057f6cd | 1312 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
b3b94faa | 1313 | { |
15562c43 | 1314 | struct lm_lockstruct *ls = &gl->gl_name.ln_sbd->sd_lockstruct; |
0809f6ec | 1315 | |
47a25380 | 1316 | spin_lock(&gl->gl_spin); |
f057f6cd | 1317 | gl->gl_reply = ret; |
0809f6ec | 1318 | |
e0c2a9aa | 1319 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) { |
0809f6ec | 1320 | if (gfs2_should_freeze(gl)) { |
f057f6cd | 1321 | set_bit(GLF_FROZEN, &gl->gl_flags); |
0809f6ec | 1322 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1323 | return; |
0809f6ec | 1324 | } |
b3b94faa | 1325 | } |
47a25380 | 1326 | |
e66cf161 | 1327 | gl->gl_lockref.count++; |
f057f6cd | 1328 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
e66cf161 SW |
1329 | spin_unlock(&gl->gl_spin); |
1330 | ||
f057f6cd SW |
1331 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1332 | gfs2_glock_put(gl); | |
b3b94faa DT |
1333 | } |
1334 | ||
4506a519 SW |
1335 | static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) |
1336 | { | |
1337 | struct gfs2_glock *gla, *glb; | |
1338 | ||
1339 | gla = list_entry(a, struct gfs2_glock, gl_lru); | |
1340 | glb = list_entry(b, struct gfs2_glock, gl_lru); | |
1341 | ||
1342 | if (gla->gl_name.ln_number > glb->gl_name.ln_number) | |
1343 | return 1; | |
1344 | if (gla->gl_name.ln_number < glb->gl_name.ln_number) | |
1345 | return -1; | |
1346 | ||
1347 | return 0; | |
1348 | } | |
1349 | ||
1350 | /** | |
1351 | * gfs2_dispose_glock_lru - Demote a list of glocks | |
1352 | * @list: The list to dispose of | |
1353 | * | |
1354 | * Disposing of glocks may involve disk accesses, so that here we sort | |
1355 | * the glocks by number (i.e. disk location of the inodes) so that if | |
1356 | * there are any such accesses, they'll be sent in order (mostly). | |
1357 | * | |
1358 | * Must be called under the lru_lock, but may drop and retake this | |
1359 | * lock. While the lru_lock is dropped, entries may vanish from the | |
1360 | * list, but no new entries will appear on the list (since it is | |
1361 | * private) | |
1362 | */ | |
1363 | ||
1364 | static void gfs2_dispose_glock_lru(struct list_head *list) | |
1365 | __releases(&lru_lock) | |
1366 | __acquires(&lru_lock) | |
1367 | { | |
1368 | struct gfs2_glock *gl; | |
1369 | ||
1370 | list_sort(NULL, list, glock_cmp); | |
1371 | ||
1372 | while(!list_empty(list)) { | |
1373 | gl = list_entry(list->next, struct gfs2_glock, gl_lru); | |
1374 | list_del_init(&gl->gl_lru); | |
e66cf161 | 1375 | if (!spin_trylock(&gl->gl_spin)) { |
94a09a39 | 1376 | add_back_to_lru: |
e66cf161 SW |
1377 | list_add(&gl->gl_lru, &lru_list); |
1378 | atomic_inc(&lru_count); | |
1379 | continue; | |
1380 | } | |
94a09a39 SW |
1381 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
1382 | spin_unlock(&gl->gl_spin); | |
1383 | goto add_back_to_lru; | |
1384 | } | |
4506a519 | 1385 | clear_bit(GLF_LRU, &gl->gl_flags); |
e66cf161 | 1386 | gl->gl_lockref.count++; |
4506a519 | 1387 | if (demote_ok(gl)) |
81ffbf65 | 1388 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
4506a519 | 1389 | WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); |
4506a519 | 1390 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 1391 | gl->gl_lockref.count--; |
4506a519 | 1392 | spin_unlock(&gl->gl_spin); |
94a09a39 | 1393 | cond_resched_lock(&lru_lock); |
4506a519 SW |
1394 | } |
1395 | } | |
1396 | ||
2a005855 SW |
1397 | /** |
1398 | * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote | |
1399 | * @nr: The number of entries to scan | |
1400 | * | |
4506a519 SW |
1401 | * This function selects the entries on the LRU which are able to |
1402 | * be demoted, and then kicks off the process by calling | |
1403 | * gfs2_dispose_glock_lru() above. | |
2a005855 | 1404 | */ |
b3b94faa | 1405 | |
1ab6c499 | 1406 | static long gfs2_scan_glock_lru(int nr) |
b3b94faa DT |
1407 | { |
1408 | struct gfs2_glock *gl; | |
97cc1025 | 1409 | LIST_HEAD(skipped); |
4506a519 | 1410 | LIST_HEAD(dispose); |
1ab6c499 | 1411 | long freed = 0; |
b3b94faa | 1412 | |
97cc1025 | 1413 | spin_lock(&lru_lock); |
1ab6c499 | 1414 | while ((nr-- >= 0) && !list_empty(&lru_list)) { |
97cc1025 | 1415 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); |
97cc1025 SW |
1416 | |
1417 | /* Test for being demotable */ | |
94a09a39 | 1418 | if (!test_bit(GLF_LOCK, &gl->gl_flags)) { |
4506a519 SW |
1419 | list_move(&gl->gl_lru, &dispose); |
1420 | atomic_dec(&lru_count); | |
1ab6c499 | 1421 | freed++; |
2163b1e6 | 1422 | continue; |
97cc1025 | 1423 | } |
4506a519 SW |
1424 | |
1425 | list_move(&gl->gl_lru, &skipped); | |
b3b94faa | 1426 | } |
97cc1025 | 1427 | list_splice(&skipped, &lru_list); |
4506a519 SW |
1428 | if (!list_empty(&dispose)) |
1429 | gfs2_dispose_glock_lru(&dispose); | |
97cc1025 | 1430 | spin_unlock(&lru_lock); |
1ab6c499 DC |
1431 | |
1432 | return freed; | |
2a005855 SW |
1433 | } |
1434 | ||
1ab6c499 DC |
1435 | static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink, |
1436 | struct shrink_control *sc) | |
2a005855 | 1437 | { |
1ab6c499 DC |
1438 | if (!(sc->gfp_mask & __GFP_FS)) |
1439 | return SHRINK_STOP; | |
1440 | return gfs2_scan_glock_lru(sc->nr_to_scan); | |
1441 | } | |
2a005855 | 1442 | |
1ab6c499 DC |
1443 | static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink, |
1444 | struct shrink_control *sc) | |
1445 | { | |
55f841ce | 1446 | return vfs_pressure_ratio(atomic_read(&lru_count)); |
b3b94faa DT |
1447 | } |
1448 | ||
97cc1025 | 1449 | static struct shrinker glock_shrinker = { |
97cc1025 | 1450 | .seeks = DEFAULT_SEEKS, |
1ab6c499 DC |
1451 | .count_objects = gfs2_glock_shrink_count, |
1452 | .scan_objects = gfs2_glock_shrink_scan, | |
97cc1025 SW |
1453 | }; |
1454 | ||
b3b94faa DT |
1455 | /** |
1456 | * examine_bucket - Call a function for glock in a hash bucket | |
1457 | * @examiner: the function | |
1458 | * @sdp: the filesystem | |
1459 | * @bucket: the bucket | |
1460 | * | |
b3b94faa DT |
1461 | */ |
1462 | ||
bc015cb8 | 1463 | static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, |
37b2fa6a | 1464 | unsigned int hash) |
b3b94faa | 1465 | { |
bc015cb8 SW |
1466 | struct gfs2_glock *gl; |
1467 | struct hlist_bl_head *head = &gl_hash_table[hash]; | |
1468 | struct hlist_bl_node *pos; | |
b3b94faa | 1469 | |
bc015cb8 SW |
1470 | rcu_read_lock(); |
1471 | hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { | |
15562c43 | 1472 | if ((gl->gl_name.ln_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref)) |
24264434 | 1473 | examiner(gl); |
b3b94faa | 1474 | } |
bc015cb8 | 1475 | rcu_read_unlock(); |
8fbbfd21 | 1476 | cond_resched(); |
bc015cb8 SW |
1477 | } |
1478 | ||
1479 | static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp) | |
1480 | { | |
1481 | unsigned x; | |
1482 | ||
1483 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
1484 | examine_bucket(examiner, sdp, x); | |
b3b94faa DT |
1485 | } |
1486 | ||
f057f6cd SW |
1487 | |
1488 | /** | |
1489 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting | |
1490 | * @gl: The glock to thaw | |
1491 | * | |
f057f6cd SW |
1492 | */ |
1493 | ||
1494 | static void thaw_glock(struct gfs2_glock *gl) | |
1495 | { | |
1496 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
7286b31e | 1497 | goto out; |
f057f6cd | 1498 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
7286b31e SW |
1499 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) { |
1500 | out: | |
f057f6cd | 1501 | gfs2_glock_put(gl); |
7286b31e | 1502 | } |
f057f6cd SW |
1503 | } |
1504 | ||
b3b94faa DT |
1505 | /** |
1506 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1507 | * @gl: the glock to look at | |
1508 | * | |
1509 | */ | |
1510 | ||
1511 | static void clear_glock(struct gfs2_glock *gl) | |
1512 | { | |
f42ab085 | 1513 | gfs2_glock_remove_from_lru(gl); |
b3b94faa | 1514 | |
6802e340 | 1515 | spin_lock(&gl->gl_spin); |
c741c455 | 1516 | if (gl->gl_state != LM_ST_UNLOCKED) |
81ffbf65 | 1517 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
6802e340 | 1518 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1519 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1520 | gfs2_glock_put(gl); | |
b3b94faa DT |
1521 | } |
1522 | ||
f057f6cd SW |
1523 | /** |
1524 | * gfs2_glock_thaw - Thaw any frozen glocks | |
1525 | * @sdp: The super block | |
1526 | * | |
1527 | */ | |
1528 | ||
1529 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) | |
1530 | { | |
bc015cb8 SW |
1531 | glock_hash_walk(thaw_glock, sdp); |
1532 | } | |
f057f6cd | 1533 | |
ac3beb6a | 1534 | static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
bc015cb8 | 1535 | { |
bc015cb8 | 1536 | spin_lock(&gl->gl_spin); |
ac3beb6a | 1537 | gfs2_dump_glock(seq, gl); |
bc015cb8 | 1538 | spin_unlock(&gl->gl_spin); |
bc015cb8 SW |
1539 | } |
1540 | ||
1541 | static void dump_glock_func(struct gfs2_glock *gl) | |
1542 | { | |
1543 | dump_glock(NULL, gl); | |
f057f6cd SW |
1544 | } |
1545 | ||
b3b94faa DT |
1546 | /** |
1547 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1548 | * @sdp: the filesystem | |
1549 | * @wait: wait until it's all gone | |
1550 | * | |
1bdad606 | 1551 | * Called when unmounting the filesystem. |
b3b94faa DT |
1552 | */ |
1553 | ||
fefc03bf | 1554 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa | 1555 | { |
fb6791d1 | 1556 | set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags); |
222cb538 | 1557 | flush_workqueue(glock_workqueue); |
bc015cb8 | 1558 | glock_hash_walk(clear_glock, sdp); |
8f05228e SW |
1559 | flush_workqueue(glock_workqueue); |
1560 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); | |
bc015cb8 | 1561 | glock_hash_walk(dump_glock_func, sdp); |
b3b94faa DT |
1562 | } |
1563 | ||
813e0c46 SW |
1564 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1565 | { | |
1566 | struct gfs2_glock *gl = ip->i_gl; | |
1567 | int ret; | |
1568 | ||
1569 | ret = gfs2_truncatei_resume(ip); | |
15562c43 | 1570 | gfs2_assert_withdraw(gl->gl_name.ln_sbd, ret == 0); |
813e0c46 SW |
1571 | |
1572 | spin_lock(&gl->gl_spin); | |
1573 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1574 | run_queue(gl, 1); | |
1575 | spin_unlock(&gl->gl_spin); | |
1576 | } | |
1577 | ||
6802e340 | 1578 | static const char *state2str(unsigned state) |
04b933f2 | 1579 | { |
6802e340 SW |
1580 | switch(state) { |
1581 | case LM_ST_UNLOCKED: | |
1582 | return "UN"; | |
1583 | case LM_ST_SHARED: | |
1584 | return "SH"; | |
1585 | case LM_ST_DEFERRED: | |
1586 | return "DF"; | |
1587 | case LM_ST_EXCLUSIVE: | |
1588 | return "EX"; | |
1589 | } | |
1590 | return "??"; | |
1591 | } | |
1592 | ||
1593 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1594 | { | |
1595 | char *p = buf; | |
1596 | if (flags & LM_FLAG_TRY) | |
1597 | *p++ = 't'; | |
1598 | if (flags & LM_FLAG_TRY_1CB) | |
1599 | *p++ = 'T'; | |
1600 | if (flags & LM_FLAG_NOEXP) | |
1601 | *p++ = 'e'; | |
1602 | if (flags & LM_FLAG_ANY) | |
f057f6cd | 1603 | *p++ = 'A'; |
6802e340 SW |
1604 | if (flags & LM_FLAG_PRIORITY) |
1605 | *p++ = 'p'; | |
1606 | if (flags & GL_ASYNC) | |
1607 | *p++ = 'a'; | |
1608 | if (flags & GL_EXACT) | |
1609 | *p++ = 'E'; | |
6802e340 SW |
1610 | if (flags & GL_NOCACHE) |
1611 | *p++ = 'c'; | |
1612 | if (test_bit(HIF_HOLDER, &iflags)) | |
1613 | *p++ = 'H'; | |
1614 | if (test_bit(HIF_WAIT, &iflags)) | |
1615 | *p++ = 'W'; | |
1616 | if (test_bit(HIF_FIRST, &iflags)) | |
1617 | *p++ = 'F'; | |
1618 | *p = 0; | |
1619 | return buf; | |
04b933f2 RP |
1620 | } |
1621 | ||
b3b94faa DT |
1622 | /** |
1623 | * dump_holder - print information about a glock holder | |
6802e340 | 1624 | * @seq: the seq_file struct |
b3b94faa DT |
1625 | * @gh: the glock holder |
1626 | * | |
b3b94faa DT |
1627 | */ |
1628 | ||
ac3beb6a | 1629 | static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1630 | { |
6802e340 | 1631 | struct task_struct *gh_owner = NULL; |
6802e340 | 1632 | char flags_buf[32]; |
b3b94faa | 1633 | |
0b3a2c99 | 1634 | rcu_read_lock(); |
6802e340 | 1635 | if (gh->gh_owner_pid) |
b1e058da | 1636 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
cc18152e JP |
1637 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
1638 | state2str(gh->gh_state), | |
1639 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1640 | gh->gh_error, | |
1641 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1642 | gh_owner ? gh_owner->comm : "(ended)", | |
1643 | (void *)gh->gh_ip); | |
0b3a2c99 | 1644 | rcu_read_unlock(); |
b3b94faa DT |
1645 | } |
1646 | ||
627c10b7 | 1647 | static const char *gflags2str(char *buf, const struct gfs2_glock *gl) |
6802e340 | 1648 | { |
627c10b7 | 1649 | const unsigned long *gflags = &gl->gl_flags; |
6802e340 | 1650 | char *p = buf; |
627c10b7 | 1651 | |
6802e340 SW |
1652 | if (test_bit(GLF_LOCK, gflags)) |
1653 | *p++ = 'l'; | |
6802e340 SW |
1654 | if (test_bit(GLF_DEMOTE, gflags)) |
1655 | *p++ = 'D'; | |
1656 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1657 | *p++ = 'd'; | |
1658 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1659 | *p++ = 'p'; | |
1660 | if (test_bit(GLF_DIRTY, gflags)) | |
1661 | *p++ = 'y'; | |
1662 | if (test_bit(GLF_LFLUSH, gflags)) | |
1663 | *p++ = 'f'; | |
1664 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1665 | *p++ = 'i'; | |
1666 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1667 | *p++ = 'r'; | |
f057f6cd | 1668 | if (test_bit(GLF_INITIAL, gflags)) |
d8348de0 | 1669 | *p++ = 'I'; |
f057f6cd SW |
1670 | if (test_bit(GLF_FROZEN, gflags)) |
1671 | *p++ = 'F'; | |
7b5e3d5f SW |
1672 | if (test_bit(GLF_QUEUED, gflags)) |
1673 | *p++ = 'q'; | |
627c10b7 SW |
1674 | if (test_bit(GLF_LRU, gflags)) |
1675 | *p++ = 'L'; | |
1676 | if (gl->gl_object) | |
1677 | *p++ = 'o'; | |
a245769f SW |
1678 | if (test_bit(GLF_BLOCKING, gflags)) |
1679 | *p++ = 'b'; | |
6802e340 SW |
1680 | *p = 0; |
1681 | return buf; | |
b3b94faa DT |
1682 | } |
1683 | ||
1684 | /** | |
8eae1ca0 | 1685 | * gfs2_dump_glock - print information about a glock |
6802e340 | 1686 | * @seq: The seq_file struct |
b3b94faa | 1687 | * @gl: the glock |
6802e340 SW |
1688 | * |
1689 | * The file format is as follows: | |
1690 | * One line per object, capital letters are used to indicate objects | |
1691 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1692 | * other objects are indented by a single space and follow the glock to | |
1693 | * which they are related. Fields are indicated by lower case letters | |
1694 | * followed by a colon and the field value, except for strings which are in | |
1695 | * [] so that its possible to see if they are composed of spaces for | |
1696 | * example. The field's are n = number (id of the object), f = flags, | |
1697 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa | 1698 | * |
b3b94faa DT |
1699 | */ |
1700 | ||
ac3beb6a | 1701 | void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1702 | { |
6802e340 SW |
1703 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1704 | unsigned long long dtime; | |
1705 | const struct gfs2_holder *gh; | |
1706 | char gflags_buf[32]; | |
b3b94faa | 1707 | |
6802e340 SW |
1708 | dtime = jiffies - gl->gl_demote_time; |
1709 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1710 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1711 | dtime = 0; | |
7cf8dcd3 | 1712 | 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 |
1713 | state2str(gl->gl_state), |
1714 | gl->gl_name.ln_type, | |
1715 | (unsigned long long)gl->gl_name.ln_number, | |
627c10b7 | 1716 | gflags2str(gflags_buf, gl), |
6802e340 SW |
1717 | state2str(gl->gl_target), |
1718 | state2str(gl->gl_demote_state), dtime, | |
6802e340 | 1719 | atomic_read(&gl->gl_ail_count), |
f42ab085 | 1720 | atomic_read(&gl->gl_revokes), |
e66cf161 | 1721 | (int)gl->gl_lockref.count, gl->gl_hold_time); |
b3b94faa | 1722 | |
ac3beb6a SW |
1723 | list_for_each_entry(gh, &gl->gl_holders, gh_list) |
1724 | dump_holder(seq, gh); | |
1725 | ||
6802e340 | 1726 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
ac3beb6a | 1727 | glops->go_dump(seq, gl); |
b3b94faa DT |
1728 | } |
1729 | ||
a245769f SW |
1730 | static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr) |
1731 | { | |
1732 | struct gfs2_glock *gl = iter_ptr; | |
1733 | ||
1734 | seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n", | |
1735 | gl->gl_name.ln_type, | |
1736 | (unsigned long long)gl->gl_name.ln_number, | |
1737 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTT], | |
1738 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR], | |
1739 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB], | |
1740 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB], | |
1741 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRT], | |
1742 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR], | |
1743 | (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT], | |
1744 | (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]); | |
1745 | return 0; | |
1746 | } | |
1747 | ||
1748 | static const char *gfs2_gltype[] = { | |
1749 | "type", | |
1750 | "reserved", | |
1751 | "nondisk", | |
1752 | "inode", | |
1753 | "rgrp", | |
1754 | "meta", | |
1755 | "iopen", | |
1756 | "flock", | |
1757 | "plock", | |
1758 | "quota", | |
1759 | "journal", | |
1760 | }; | |
1761 | ||
1762 | static const char *gfs2_stype[] = { | |
1763 | [GFS2_LKS_SRTT] = "srtt", | |
1764 | [GFS2_LKS_SRTTVAR] = "srttvar", | |
1765 | [GFS2_LKS_SRTTB] = "srttb", | |
1766 | [GFS2_LKS_SRTTVARB] = "srttvarb", | |
1767 | [GFS2_LKS_SIRT] = "sirt", | |
1768 | [GFS2_LKS_SIRTVAR] = "sirtvar", | |
1769 | [GFS2_LKS_DCOUNT] = "dlm", | |
1770 | [GFS2_LKS_QCOUNT] = "queue", | |
1771 | }; | |
1772 | ||
1773 | #define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype)) | |
1774 | ||
1775 | static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr) | |
1776 | { | |
81648d04 AG |
1777 | struct gfs2_sbd *sdp = seq->private; |
1778 | loff_t pos = *(loff_t *)iter_ptr; | |
1779 | unsigned index = pos >> 3; | |
1780 | unsigned subindex = pos & 0x07; | |
a245769f SW |
1781 | s64 value; |
1782 | int i; | |
1783 | ||
1784 | if (index == 0 && subindex != 0) | |
1785 | return 0; | |
6802e340 | 1786 | |
a245769f SW |
1787 | seq_printf(seq, "%-10s %8s:", gfs2_gltype[index], |
1788 | (index == 0) ? "cpu": gfs2_stype[subindex]); | |
b3b94faa | 1789 | |
a245769f SW |
1790 | for_each_possible_cpu(i) { |
1791 | const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i); | |
1792 | if (index == 0) { | |
1793 | value = i; | |
1794 | } else { | |
1795 | value = lkstats->lkstats[index - 1].stats[subindex]; | |
1796 | } | |
1797 | seq_printf(seq, " %15lld", (long long)value); | |
1798 | } | |
1799 | seq_putc(seq, '\n'); | |
1800 | return 0; | |
1801 | } | |
8fbbfd21 | 1802 | |
85d1da67 SW |
1803 | int __init gfs2_glock_init(void) |
1804 | { | |
1805 | unsigned i; | |
1806 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
bc015cb8 | 1807 | INIT_HLIST_BL_HEAD(&gl_hash_table[i]); |
087efdd3 | 1808 | } |
8fbbfd21 | 1809 | |
d2115778 | 1810 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
58a69cb4 | 1811 | WQ_HIGHPRI | WQ_FREEZABLE, 0); |
dfc4616d DC |
1812 | if (!glock_workqueue) |
1813 | return -ENOMEM; | |
d2115778 | 1814 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
58a69cb4 | 1815 | WQ_MEM_RECLAIM | WQ_FREEZABLE, |
d2115778 | 1816 | 0); |
dfc4616d | 1817 | if (!gfs2_delete_workqueue) { |
b94a170e | 1818 | destroy_workqueue(glock_workqueue); |
dfc4616d | 1819 | return -ENOMEM; |
b94a170e | 1820 | } |
97cc1025 SW |
1821 | |
1822 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1823 | |
85d1da67 SW |
1824 | return 0; |
1825 | } | |
1826 | ||
8fbbfd21 SW |
1827 | void gfs2_glock_exit(void) |
1828 | { | |
97cc1025 | 1829 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1830 | destroy_workqueue(glock_workqueue); |
b94a170e | 1831 | destroy_workqueue(gfs2_delete_workqueue); |
8fbbfd21 SW |
1832 | } |
1833 | ||
bc015cb8 SW |
1834 | static inline struct gfs2_glock *glock_hash_chain(unsigned hash) |
1835 | { | |
1836 | return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]), | |
1837 | struct gfs2_glock, gl_list); | |
1838 | } | |
1839 | ||
1840 | static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl) | |
1841 | { | |
7e32d026 | 1842 | return hlist_bl_entry(rcu_dereference(gl->gl_list.next), |
bc015cb8 SW |
1843 | struct gfs2_glock, gl_list); |
1844 | } | |
1845 | ||
6802e340 | 1846 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1847 | { |
7b08fc62 SW |
1848 | struct gfs2_glock *gl; |
1849 | ||
bc015cb8 SW |
1850 | do { |
1851 | gl = gi->gl; | |
1852 | if (gl) { | |
1853 | gi->gl = glock_hash_next(gl); | |
ba1ddcb6 | 1854 | gi->nhash++; |
bc015cb8 | 1855 | } else { |
ba1ddcb6 SW |
1856 | if (gi->hash >= GFS2_GL_HASH_SIZE) { |
1857 | rcu_read_unlock(); | |
1858 | return 1; | |
1859 | } | |
bc015cb8 | 1860 | gi->gl = glock_hash_chain(gi->hash); |
ba1ddcb6 | 1861 | gi->nhash = 0; |
bc015cb8 SW |
1862 | } |
1863 | while (gi->gl == NULL) { | |
1864 | gi->hash++; | |
1865 | if (gi->hash >= GFS2_GL_HASH_SIZE) { | |
1866 | rcu_read_unlock(); | |
1867 | return 1; | |
1868 | } | |
1869 | gi->gl = glock_hash_chain(gi->hash); | |
ba1ddcb6 | 1870 | gi->nhash = 0; |
bc015cb8 SW |
1871 | } |
1872 | /* Skip entries for other sb and dead entries */ | |
15562c43 | 1873 | } while (gi->sdp != gi->gl->gl_name.ln_sbd || |
e3c4269d | 1874 | __lockref_is_dead(&gi->gl->gl_lockref)); |
a947e033 | 1875 | |
7c52b166 RP |
1876 | return 0; |
1877 | } | |
1878 | ||
6802e340 | 1879 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1880 | { |
6802e340 | 1881 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1882 | loff_t n = *pos; |
1883 | ||
ba1ddcb6 SW |
1884 | if (gi->last_pos <= *pos) |
1885 | n = gi->nhash + (*pos - gi->last_pos); | |
1886 | else | |
1887 | gi->hash = 0; | |
1888 | ||
1889 | gi->nhash = 0; | |
bc015cb8 | 1890 | rcu_read_lock(); |
7c52b166 | 1891 | |
6802e340 | 1892 | do { |
bc015cb8 | 1893 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1894 | return NULL; |
6802e340 | 1895 | } while (n--); |
7c52b166 | 1896 | |
ba1ddcb6 | 1897 | gi->last_pos = *pos; |
6802e340 | 1898 | return gi->gl; |
7c52b166 RP |
1899 | } |
1900 | ||
6802e340 | 1901 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1902 | loff_t *pos) |
1903 | { | |
6802e340 | 1904 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1905 | |
1906 | (*pos)++; | |
ba1ddcb6 | 1907 | gi->last_pos = *pos; |
bc015cb8 | 1908 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1909 | return NULL; |
7c52b166 | 1910 | |
6802e340 | 1911 | return gi->gl; |
7c52b166 RP |
1912 | } |
1913 | ||
6802e340 | 1914 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1915 | { |
6802e340 | 1916 | struct gfs2_glock_iter *gi = seq->private; |
bc015cb8 SW |
1917 | |
1918 | if (gi->gl) | |
1919 | rcu_read_unlock(); | |
1920 | gi->gl = NULL; | |
7c52b166 RP |
1921 | } |
1922 | ||
6802e340 | 1923 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1924 | { |
ac3beb6a SW |
1925 | dump_glock(seq, iter_ptr); |
1926 | return 0; | |
7c52b166 RP |
1927 | } |
1928 | ||
a245769f SW |
1929 | static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos) |
1930 | { | |
81648d04 | 1931 | preempt_disable(); |
a245769f SW |
1932 | if (*pos >= GFS2_NR_SBSTATS) |
1933 | return NULL; | |
81648d04 | 1934 | return pos; |
a245769f SW |
1935 | } |
1936 | ||
1937 | static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr, | |
1938 | loff_t *pos) | |
1939 | { | |
a245769f | 1940 | (*pos)++; |
81648d04 | 1941 | if (*pos >= GFS2_NR_SBSTATS) |
a245769f | 1942 | return NULL; |
81648d04 | 1943 | return pos; |
a245769f SW |
1944 | } |
1945 | ||
1946 | static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr) | |
1947 | { | |
1948 | preempt_enable(); | |
1949 | } | |
1950 | ||
4ef29002 | 1951 | static const struct seq_operations gfs2_glock_seq_ops = { |
7c52b166 RP |
1952 | .start = gfs2_glock_seq_start, |
1953 | .next = gfs2_glock_seq_next, | |
1954 | .stop = gfs2_glock_seq_stop, | |
1955 | .show = gfs2_glock_seq_show, | |
1956 | }; | |
1957 | ||
a245769f SW |
1958 | static const struct seq_operations gfs2_glstats_seq_ops = { |
1959 | .start = gfs2_glock_seq_start, | |
1960 | .next = gfs2_glock_seq_next, | |
1961 | .stop = gfs2_glock_seq_stop, | |
1962 | .show = gfs2_glstats_seq_show, | |
1963 | }; | |
1964 | ||
1965 | static const struct seq_operations gfs2_sbstats_seq_ops = { | |
1966 | .start = gfs2_sbstats_seq_start, | |
1967 | .next = gfs2_sbstats_seq_next, | |
1968 | .stop = gfs2_sbstats_seq_stop, | |
1969 | .show = gfs2_sbstats_seq_show, | |
1970 | }; | |
1971 | ||
0fe2f1e9 SW |
1972 | #define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL) |
1973 | ||
a245769f | 1974 | static int gfs2_glocks_open(struct inode *inode, struct file *file) |
7c52b166 | 1975 | { |
6802e340 SW |
1976 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
1977 | sizeof(struct gfs2_glock_iter)); | |
1978 | if (ret == 0) { | |
1979 | struct seq_file *seq = file->private_data; | |
1980 | struct gfs2_glock_iter *gi = seq->private; | |
1981 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 1982 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 1983 | if (seq->buf) |
0fe2f1e9 | 1984 | seq->size = GFS2_SEQ_GOODSIZE; |
6802e340 SW |
1985 | } |
1986 | return ret; | |
7c52b166 RP |
1987 | } |
1988 | ||
a245769f SW |
1989 | static int gfs2_glstats_open(struct inode *inode, struct file *file) |
1990 | { | |
1991 | int ret = seq_open_private(file, &gfs2_glstats_seq_ops, | |
1992 | sizeof(struct gfs2_glock_iter)); | |
1993 | if (ret == 0) { | |
1994 | struct seq_file *seq = file->private_data; | |
1995 | struct gfs2_glock_iter *gi = seq->private; | |
1996 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 1997 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 1998 | if (seq->buf) |
0fe2f1e9 | 1999 | seq->size = GFS2_SEQ_GOODSIZE; |
a245769f SW |
2000 | } |
2001 | return ret; | |
2002 | } | |
2003 | ||
2004 | static int gfs2_sbstats_open(struct inode *inode, struct file *file) | |
2005 | { | |
81648d04 | 2006 | int ret = seq_open(file, &gfs2_sbstats_seq_ops); |
a245769f SW |
2007 | if (ret == 0) { |
2008 | struct seq_file *seq = file->private_data; | |
81648d04 | 2009 | seq->private = inode->i_private; /* sdp */ |
a245769f SW |
2010 | } |
2011 | return ret; | |
2012 | } | |
2013 | ||
2014 | static const struct file_operations gfs2_glocks_fops = { | |
2015 | .owner = THIS_MODULE, | |
2016 | .open = gfs2_glocks_open, | |
2017 | .read = seq_read, | |
2018 | .llseek = seq_lseek, | |
2019 | .release = seq_release_private, | |
2020 | }; | |
2021 | ||
2022 | static const struct file_operations gfs2_glstats_fops = { | |
7c52b166 | 2023 | .owner = THIS_MODULE, |
a245769f SW |
2024 | .open = gfs2_glstats_open, |
2025 | .read = seq_read, | |
2026 | .llseek = seq_lseek, | |
2027 | .release = seq_release_private, | |
2028 | }; | |
2029 | ||
2030 | static const struct file_operations gfs2_sbstats_fops = { | |
2031 | .owner = THIS_MODULE, | |
2032 | .open = gfs2_sbstats_open, | |
7c52b166 RP |
2033 | .read = seq_read, |
2034 | .llseek = seq_lseek, | |
81648d04 | 2035 | .release = seq_release, |
7c52b166 RP |
2036 | }; |
2037 | ||
2038 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
2039 | { | |
7b4ddfa7 CS |
2040 | struct dentry *dent; |
2041 | ||
2042 | dent = debugfs_create_dir(sdp->sd_table_name, gfs2_root); | |
2043 | if (IS_ERR_OR_NULL(dent)) | |
2044 | goto fail; | |
2045 | sdp->debugfs_dir = dent; | |
2046 | ||
2047 | dent = debugfs_create_file("glocks", | |
2048 | S_IFREG | S_IRUGO, | |
2049 | sdp->debugfs_dir, sdp, | |
2050 | &gfs2_glocks_fops); | |
2051 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2052 | goto fail; |
7b4ddfa7 | 2053 | sdp->debugfs_dentry_glocks = dent; |
a245769f | 2054 | |
7b4ddfa7 CS |
2055 | dent = debugfs_create_file("glstats", |
2056 | S_IFREG | S_IRUGO, | |
2057 | sdp->debugfs_dir, sdp, | |
2058 | &gfs2_glstats_fops); | |
2059 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2060 | goto fail; |
7b4ddfa7 | 2061 | sdp->debugfs_dentry_glstats = dent; |
a245769f | 2062 | |
7b4ddfa7 CS |
2063 | dent = debugfs_create_file("sbstats", |
2064 | S_IFREG | S_IRUGO, | |
2065 | sdp->debugfs_dir, sdp, | |
2066 | &gfs2_sbstats_fops); | |
2067 | if (IS_ERR_OR_NULL(dent)) | |
a245769f | 2068 | goto fail; |
7b4ddfa7 | 2069 | sdp->debugfs_dentry_sbstats = dent; |
7c52b166 RP |
2070 | |
2071 | return 0; | |
a245769f SW |
2072 | fail: |
2073 | gfs2_delete_debugfs_file(sdp); | |
7b4ddfa7 | 2074 | return dent ? PTR_ERR(dent) : -ENOMEM; |
7c52b166 RP |
2075 | } |
2076 | ||
2077 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) | |
2078 | { | |
a245769f | 2079 | if (sdp->debugfs_dir) { |
5f882096 RP |
2080 | if (sdp->debugfs_dentry_glocks) { |
2081 | debugfs_remove(sdp->debugfs_dentry_glocks); | |
2082 | sdp->debugfs_dentry_glocks = NULL; | |
2083 | } | |
a245769f SW |
2084 | if (sdp->debugfs_dentry_glstats) { |
2085 | debugfs_remove(sdp->debugfs_dentry_glstats); | |
2086 | sdp->debugfs_dentry_glstats = NULL; | |
2087 | } | |
2088 | if (sdp->debugfs_dentry_sbstats) { | |
2089 | debugfs_remove(sdp->debugfs_dentry_sbstats); | |
2090 | sdp->debugfs_dentry_sbstats = NULL; | |
2091 | } | |
5f882096 RP |
2092 | debugfs_remove(sdp->debugfs_dir); |
2093 | sdp->debugfs_dir = NULL; | |
2094 | } | |
7c52b166 RP |
2095 | } |
2096 | ||
2097 | int gfs2_register_debugfs(void) | |
2098 | { | |
2099 | gfs2_root = debugfs_create_dir("gfs2", NULL); | |
7b4ddfa7 CS |
2100 | if (IS_ERR(gfs2_root)) |
2101 | return PTR_ERR(gfs2_root); | |
7c52b166 RP |
2102 | return gfs2_root ? 0 : -ENOMEM; |
2103 | } | |
2104 | ||
2105 | void gfs2_unregister_debugfs(void) | |
2106 | { | |
2107 | debugfs_remove(gfs2_root); | |
5f882096 | 2108 | gfs2_root = NULL; |
7c52b166 | 2109 | } |