blob: a38e38f7b6fc37ae2e2b9ca5af0e59d7c5652856 [file] [log] [blame]
David Teiglandb3b94fa2006-01-16 16:50:04 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
Bob Petersoncf45b752008-01-31 10:31:39 -06003 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
David Teiglandb3b94fa2006-01-16 16:50:04 +00004 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
Steven Whitehousee9fc2aa2006-09-01 11:05:15 -04007 * of the GNU General Public License version 2.
David Teiglandb3b94fa2006-01-16 16:50:04 +00008 */
9
Joe Perchesd77d1b52014-03-06 12:10:45 -080010#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
David Teiglandb3b94fa2006-01-16 16:50:04 +000012#include <linux/sched.h>
13#include <linux/slab.h>
14#include <linux/spinlock.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000015#include <linux/buffer_head.h>
16#include <linux/delay.h>
17#include <linux/sort.h>
18#include <linux/jhash.h>
Steven Whitehoused0dc80d2006-03-29 14:36:49 -050019#include <linux/kallsyms.h>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050020#include <linux/gfs2_ondisk.h>
Steven Whitehouse24264432006-09-11 21:40:30 -040021#include <linux/list.h>
Steven Whitehousefee852e2007-01-17 15:33:23 +000022#include <linux/wait.h>
akpm@linux-foundation.org95d97b72007-03-05 23:10:39 -080023#include <linux/module.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000024#include <asm/uaccess.h>
Robert Peterson7c52b162007-03-16 10:26:37 +000025#include <linux/seq_file.h>
26#include <linux/debugfs.h>
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +010027#include <linux/kthread.h>
28#include <linux/freezer.h>
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050029#include <linux/workqueue.h>
30#include <linux/jiffies.h>
Steven Whitehousebc015cb2011-01-19 09:30:01 +000031#include <linux/rcupdate.h>
32#include <linux/rculist_bl.h>
33#include <linux/bit_spinlock.h>
Steven Whitehousea2457692012-01-20 10:38:36 +000034#include <linux/percpu.h>
Steven Whitehouse4506a512013-02-01 20:36:03 +000035#include <linux/list_sort.h>
Steven Whitehousee66cf162013-10-15 15:18:08 +010036#include <linux/lockref.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000037
38#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050039#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000040#include "glock.h"
41#include "glops.h"
42#include "inode.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000043#include "lops.h"
44#include "meta_io.h"
45#include "quota.h"
46#include "super.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050047#include "util.h"
Steven Whitehouse813e0c42008-11-18 13:38:48 +000048#include "bmap.h"
Steven Whitehouse63997772009-06-12 08:49:20 +010049#define CREATE_TRACE_POINTS
50#include "trace_gfs2.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000051
Steven Whitehouse6802e342008-05-21 17:03:22 +010052struct gfs2_glock_iter {
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +010053 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 */
Robert Peterson7c52b162007-03-16 10:26:37 +000058};
59
David Teiglandb3b94fa2006-01-16 16:50:04 +000060typedef void (*glock_examiner) (struct gfs2_glock * gl);
61
Steven Whitehouse6802e342008-05-21 17:03:22 +010062static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050063
Robert Peterson7c52b162007-03-16 10:26:37 +000064static struct dentry *gfs2_root;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050065static struct workqueue_struct *glock_workqueue;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -050066struct workqueue_struct *gfs2_delete_workqueue;
Steven Whitehouse97cc1022008-11-20 13:39:47 +000067static LIST_HEAD(lru_list);
68static atomic_t lru_count = ATOMIC_INIT(0);
Julia Lawalleb8374e2008-12-25 15:35:27 +010069static DEFINE_SPINLOCK(lru_lock);
Adrian Bunk08bc2db2006-04-28 10:59:12 -040070
Steven Whitehouseb6397892006-09-12 10:10:01 -040071#define GFS2_GL_HASH_SHIFT 15
Steven Whitehouse087efdd2006-09-09 16:59:11 -040072#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
73#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
74
Steven Whitehousebc015cb2011-01-19 09:30:01 +000075static struct hlist_bl_head gl_hash_table[GFS2_GL_HASH_SIZE];
Robert Peterson04b933f2007-03-23 17:05:15 -050076static struct dentry *gfs2_root;
Steven Whitehouse087efdd2006-09-09 16:59:11 -040077
David Teiglandb3b94fa2006-01-16 16:50:04 +000078/**
David Teiglandb3b94fa2006-01-16 16:50:04 +000079 * 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
Steven Whitehouseb8547852006-09-07 13:12:27 -040085static unsigned int gl_hash(const struct gfs2_sbd *sdp,
86 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +000087{
88 unsigned int h;
89
Steven Whitehousecd915492006-09-04 12:49:07 -040090 h = jhash(&name->ln_number, sizeof(u64), 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +000091 h = jhash(&name->ln_type, sizeof(unsigned int), h);
Steven Whitehouseb8547852006-09-07 13:12:27 -040092 h = jhash(&sdp, sizeof(struct gfs2_sbd *), h);
David Teiglandb3b94fa2006-01-16 16:50:04 +000093 h &= GFS2_GL_HASH_MASK;
94
95 return h;
96}
97
Steven Whitehousebc015cb2011-01-19 09:30:01 +000098static inline void spin_lock_bucket(unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +000099{
Christoph Hellwig1879fd62011-04-25 14:01:36 -0400100 hlist_bl_lock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000101}
David Teiglandb3b94fa2006-01-16 16:50:04 +0000102
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000103static inline void spin_unlock_bucket(unsigned int hash)
104{
Christoph Hellwig1879fd62011-04-25 14:01:36 -0400105 hlist_bl_unlock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000106}
107
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000108static void gfs2_glock_dealloc(struct rcu_head *rcu)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000109{
110 struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000111
David Teiglanddba2d702012-11-14 13:46:53 -0500112 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000113 kmem_cache_free(gfs2_glock_aspace_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500114 } else {
David Teigland4e2f8842012-11-14 13:47:37 -0500115 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000116 kmem_cache_free(gfs2_glock_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500117 }
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000118}
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000119
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000120void gfs2_glock_free(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000121{
122 struct gfs2_sbd *sdp = gl->gl_sbd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000123
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000124 call_rcu(&gl->gl_rcu, gfs2_glock_dealloc);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000125 if (atomic_dec_and_test(&sdp->sd_glock_disposal))
126 wake_up(&sdp->sd_glock_wait);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000127}
128
129/**
130 * gfs2_glock_hold() - increment reference count on glock
131 * @gl: The glock to hold
132 *
133 */
134
Steven Whitehousee66cf162013-10-15 15:18:08 +0100135static void gfs2_glock_hold(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000136{
Steven Whitehousee66cf162013-10-15 15:18:08 +0100137 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
138 lockref_get(&gl->gl_lockref);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000139}
140
141/**
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500142 * 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
148static 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;
Steven Whitehousef42ab082011-04-14 16:50:31 +0100154 if (!list_empty(&gl->gl_holders))
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500155 return 0;
156 if (glops->go_demote_ok)
157 return glops->go_demote_ok(gl);
158 return 1;
159}
160
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000161
Steven Whitehouse29687a22011-03-30 16:33:25 +0100162void 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);
Steven Whitehouse627c10b2011-04-14 14:09:52 +0100172 set_bit(GLF_LRU, &gl->gl_flags);
Steven Whitehouse29687a22011-03-30 16:33:25 +0100173 spin_unlock(&lru_lock);
174}
175
Bob Peterson8f6cb402015-01-05 13:25:10 -0500176static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
Steven Whitehousef42ab082011-04-14 16:50:31 +0100177{
Bob Peterson8f6cb402015-01-05 13:25:10 -0500178 spin_lock(&lru_lock);
Steven Whitehousef42ab082011-04-14 16:50:31 +0100179 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
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500187/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000188 * gfs2_glock_put() - Decrement reference count on glock
189 * @gl: The glock to put
190 *
191 */
192
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000193void gfs2_glock_put(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000194{
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000195 struct gfs2_sbd *sdp = gl->gl_sbd;
196 struct address_space *mapping = gfs2_glock2aspace(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000197
Steven Whitehousee66cf162013-10-15 15:18:08 +0100198 if (lockref_put_or_lock(&gl->gl_lockref))
199 return;
200
201 lockref_mark_dead(&gl->gl_lockref);
202
Bob Peterson8f6cb402015-01-05 13:25:10 -0500203 gfs2_glock_remove_from_lru(gl);
Steven Whitehousee66cf162013-10-15 15:18:08 +0100204 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);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000212}
213
214/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000215 * 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
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400222static struct gfs2_glock *search_bucket(unsigned int hash,
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400223 const struct gfs2_sbd *sdp,
Steven Whitehoused6a53722006-08-30 11:16:23 -0400224 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000225{
226 struct gfs2_glock *gl;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000227 struct hlist_bl_node *h;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000228
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000229 hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000230 if (!lm_name_equal(&gl->gl_name, name))
231 continue;
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400232 if (gl->gl_sbd != sdp)
233 continue;
Steven Whitehousee66cf162013-10-15 15:18:08 +0100234 if (lockref_get_not_dead(&gl->gl_lockref))
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000235 return gl;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000236 }
237
238 return NULL;
239}
240
241/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100242 * 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
249static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh)
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500250{
Steven Whitehouse6802e342008-05-21 17:03:22 +0100251 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;
Steven Whitehouse209806a2008-07-07 10:07:28 +0100259 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 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100265 if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY))
266 return 1;
267 return 0;
268}
269
270static void gfs2_holder_wake(struct gfs2_holder *gh)
271{
272 clear_bit(HIF_WAIT, &gh->gh_iflags);
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100273 smp_mb__after_atomic();
Steven Whitehouse6802e342008-05-21 17:03:22 +0100274 wake_up_bit(&gh->gh_iflags, HIF_WAIT);
275}
276
277/**
Steven Whitehoused5341a92010-07-23 14:05:51 +0100278 * do_error - Something unexpected has happened during a lock request
279 *
280 */
281
282static 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
301/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100302 * do_promote - promote as many requests as possible on the current queue
303 * @gl: The glock
304 *
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000305 * Returns: 1 if there is a blocked holder at the head of the list, or 2
306 * if a type specific operation is underway.
Steven Whitehouse6802e342008-05-21 17:03:22 +0100307 */
308
309static int do_promote(struct gfs2_glock *gl)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700310__releases(&gl->gl_spin)
311__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100312{
313 const struct gfs2_glock_operations *glops = gl->gl_ops;
314 struct gfs2_holder *gh, *tmp;
315 int ret;
316
317restart:
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) {
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000329 if (ret == 1)
330 return 2;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100331 gh->gh_error = ret;
332 list_del_init(&gh->gh_list);
Steven Whitehouse63997772009-06-12 08:49:20 +0100333 trace_gfs2_glock_queue(gh, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100334 gfs2_holder_wake(gh);
335 goto restart;
336 }
337 set_bit(HIF_HOLDER, &gh->gh_iflags);
Steven Whitehouse63997772009-06-12 08:49:20 +0100338 trace_gfs2_promote(gh, 1);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100339 gfs2_holder_wake(gh);
340 goto restart;
341 }
342 set_bit(HIF_HOLDER, &gh->gh_iflags);
Steven Whitehouse63997772009-06-12 08:49:20 +0100343 trace_gfs2_promote(gh, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100344 gfs2_holder_wake(gh);
345 continue;
346 }
347 if (gh->gh_list.prev == &gl->gl_holders)
348 return 1;
Steven Whitehoused5341a92010-07-23 14:05:51 +0100349 do_error(gl, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100350 break;
351 }
352 return 0;
353}
354
355/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100356 * find_first_waiter - find the first gh that's waiting for the glock
357 * @gl: the glock
358 */
359
360static 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
378static 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) {
Steven Whitehousee66cf162013-10-15 15:18:08 +0100386 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
Steven Whitehouse6802e342008-05-21 17:03:22 +0100387 if (held2)
Steven Whitehousee66cf162013-10-15 15:18:08 +0100388 gl->gl_lockref.count++;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100389 else
Steven Whitehousee66cf162013-10-15 15:18:08 +0100390 gl->gl_lockref.count--;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100391 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100392 if (held1 && held2 && list_empty(&gl->gl_holders))
393 clear_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100394
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400395 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);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100399 gl->gl_state = new_state;
400 gl->gl_tchange = jiffies;
401}
402
403static 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);
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100407 smp_mb__after_atomic();
Steven Whitehouse6802e342008-05-21 17:03:22 +0100408 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
418static 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;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000423 int rv;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500424
425 spin_lock(&gl->gl_spin);
Steven Whitehouse63997772009-06-12 08:49:20 +0100426 trace_gfs2_glock_state_change(gl, state);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100427 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:
457retry:
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 */
Joe Perchesd77d1b52014-03-06 12:10:45 -0800466 pr_err("wanted %u got %u\n", gl->gl_target, state);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100467 GLOCK_BUG_ON(gl, 1);
468 }
469 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100470 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) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100478 spin_unlock(&gl->gl_spin);
479 rv = glops->go_xmote_bh(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100480 spin_lock(&gl->gl_spin);
481 if (rv) {
482 do_error(gl, rv);
483 goto out;
484 }
485 }
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000486 rv = do_promote(gl);
487 if (rv == 2)
488 goto out_locked;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100489 }
490out:
491 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000492out_locked:
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500493 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500494}
495
Steven Whitehouse6802e342008-05-21 17:03:22 +0100496/**
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
504static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700505__releases(&gl->gl_spin)
506__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100507{
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);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000515 GLOCK_BUG_ON(gl, gl->gl_state == target);
516 GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100517 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 }
Steven Whitehouse47a25382010-11-30 15:49:31 +0000522 gl->gl_req = target;
Steven Whitehousea2457692012-01-20 10:38:36 +0000523 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);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100528 spin_unlock(&gl->gl_spin);
Bob Peterson06dfc302012-10-24 14:41:05 -0400529 if (glops->go_sync)
530 glops->go_sync(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100531 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);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000536 if (sdp->sd_lockstruct.ls_ops->lm_lock) {
537 /* lock_dlm */
538 ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
David Teiglanddba2d702012-11-14 13:46:53 -0500539 if (ret) {
Joe Perchesd77d1b52014-03-06 12:10:45 -0800540 pr_err("lm_lock ret %d\n", ret);
David Teiglanddba2d702012-11-14 13:46:53 -0500541 GLOCK_BUG_ON(gl, 1);
542 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000543 } else { /* lock_nolock */
544 finish_xmote(gl, target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100545 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
546 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100547 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000548
Steven Whitehouse6802e342008-05-21 17:03:22 +0100549 spin_lock(&gl->gl_spin);
550}
551
552/**
553 * find_first_holder - find the first "holder" gh
554 * @gl: the glock
555 */
556
557static 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
576static void run_queue(struct gfs2_glock *gl, const int nonblock)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700577__releases(&gl->gl_spin)
578__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100579{
580 struct gfs2_holder *gh = NULL;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000581 int ret;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100582
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))
Steven Whitehoused8348de2009-02-05 10:12:38 +0000591 goto out_unlock;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100592 if (nonblock)
593 goto out_sched;
594 set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100595 GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100596 gl->gl_target = gl->gl_demote_state;
597 } else {
598 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
599 gfs2_demote_wake(gl);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000600 ret = do_promote(gl);
601 if (ret == 0)
Steven Whitehoused8348de2009-02-05 10:12:38 +0000602 goto out_unlock;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000603 if (ret == 2)
Steven Whitehousea228df62009-04-07 14:01:34 +0100604 goto out;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100605 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);
Steven Whitehousea228df62009-04-07 14:01:34 +0100611out:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100612 return;
613
614out_sched:
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100615 clear_bit(GLF_LOCK, &gl->gl_flags);
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100616 smp_mb__after_atomic();
Steven Whitehousee66cf162013-10-15 15:18:08 +0100617 gl->gl_lockref.count++;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100618 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
Steven Whitehousee66cf162013-10-15 15:18:08 +0100619 gl->gl_lockref.count--;
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100620 return;
621
Steven Whitehoused8348de2009-02-05 10:12:38 +0000622out_unlock:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100623 clear_bit(GLF_LOCK, &gl->gl_flags);
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100624 smp_mb__after_atomic();
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100625 return;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100626}
627
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500628static 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;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000632 struct gfs2_inode *ip;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500633 struct inode *inode;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000634 u64 no_addr = gl->gl_name.ln_number;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500635
Steven Whitehouse044b9412010-11-03 20:01:07 +0000636 ip = gl->gl_object;
637 /* Note: Unsafe to dereference ip as we don't hold right refs/locks */
638
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500639 if (ip)
Steven Whitehouse4667a0e2011-04-18 14:18:09 +0100640 inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1);
Steven Whitehouse044b9412010-11-03 20:01:07 +0000641 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);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500646 }
647 gfs2_glock_put(gl);
648}
649
Steven Whitehouse6802e342008-05-21 17:03:22 +0100650static void glock_work_func(struct work_struct *work)
651{
652 unsigned long delay = 0;
653 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000654 int drop_ref = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100655
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000656 if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100657 finish_xmote(gl, gl->gl_reply);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000658 drop_ref = 1;
659 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100660 spin_lock(&gl->gl_spin);
Bob Petersonf90e5b52011-05-24 10:44:42 -0400661 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100662 gl->gl_state != LM_ST_UNLOCKED &&
663 gl->gl_demote_state != LM_ST_EXCLUSIVE) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100664 unsigned long holdtime, now = jiffies;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400665
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400666 holdtime = gl->gl_tchange + gl->gl_hold_time;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100667 if (time_before(now, holdtime))
668 delay = holdtime - now;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400669
670 if (!delay) {
671 clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
672 set_bit(GLF_DEMOTE, &gl->gl_flags);
673 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100674 }
675 run_queue(gl, 0);
676 spin_unlock(&gl->gl_spin);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400677 if (!delay)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100678 gfs2_glock_put(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400679 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 }
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000685 if (drop_ref)
686 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100687}
688
David Teiglandb3b94fa2006-01-16 16:50:04 +0000689/**
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
Steven Whitehousecd915492006-09-04 12:49:07 -0400702int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400703 const struct gfs2_glock_operations *glops, int create,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000704 struct gfs2_glock **glp)
705{
Steven Whitehouse009d8512009-12-08 12:12:13 +0000706 struct super_block *s = sdp->sd_vfs;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400707 struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type };
David Teiglandb3b94fa2006-01-16 16:50:04 +0000708 struct gfs2_glock *gl, *tmp;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400709 unsigned int hash = gl_hash(sdp, &name);
Steven Whitehouse009d8512009-12-08 12:12:13 +0000710 struct address_space *mapping;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000711 struct kmem_cache *cachep;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000712
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000713 rcu_read_lock();
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400714 gl = search_bucket(hash, sdp, &name);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000715 rcu_read_unlock();
David Teiglandb3b94fa2006-01-16 16:50:04 +0000716
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000717 *glp = gl;
718 if (gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000719 return 0;
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000720 if (!create)
721 return -ENOENT;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000722
Steven Whitehouse009d8512009-12-08 12:12:13 +0000723 if (glops->go_flags & GLOF_ASPACE)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000724 cachep = gfs2_glock_aspace_cachep;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000725 else
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000726 cachep = gfs2_glock_cachep;
Steven Whitehousefe0bbd22014-06-23 14:50:20 +0100727 gl = kmem_cache_alloc(cachep, GFP_NOFS);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000728 if (!gl)
729 return -ENOMEM;
730
David Teiglanddba2d702012-11-14 13:46:53 -0500731 memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
David Teiglanddba2d702012-11-14 13:46:53 -0500732
733 if (glops->go_flags & GLOF_LVB) {
Steven Whitehousefe0bbd22014-06-23 14:50:20 +0100734 gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_NOFS);
David Teigland4e2f8842012-11-14 13:47:37 -0500735 if (!gl->gl_lksb.sb_lvbptr) {
David Teiglanddba2d702012-11-14 13:46:53 -0500736 kmem_cache_free(cachep, gl);
737 return -ENOMEM;
738 }
David Teiglanddba2d702012-11-14 13:46:53 -0500739 }
740
Steven Whitehouse8f052282010-01-29 15:21:27 +0000741 atomic_inc(&sdp->sd_glock_disposal);
Steven Whitehousea2457692012-01-20 10:38:36 +0000742 gl->gl_sbd = sdp;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400743 gl->gl_flags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000744 gl->gl_name = name;
Steven Whitehousee66cf162013-10-15 15:18:08 +0100745 gl->gl_lockref.count = 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000746 gl->gl_state = LM_ST_UNLOCKED;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100747 gl->gl_target = LM_ST_UNLOCKED;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500748 gl->gl_demote_state = LM_ST_EXCLUSIVE;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400749 gl->gl_hash = hash;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000750 gl->gl_ops = glops;
Steven Whitehousea2457692012-01-20 10:38:36 +0000751 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;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500758 gl->gl_tchange = jiffies;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400759 gl->gl_object = NULL;
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400760 gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500761 INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500762 INIT_WORK(&gl->gl_delete, delete_work_func);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000763
Steven Whitehouse009d8512009-12-08 12:12:13 +0000764 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);
Rafael Aquini252aa6f2012-12-11 16:02:35 -0800770 mapping->private_data = NULL;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000771 mapping->writeback_index = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000772 }
773
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000774 spin_lock_bucket(hash);
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400775 tmp = search_bucket(hash, sdp, &name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000776 if (tmp) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000777 spin_unlock_bucket(hash);
David Teigland4e2f8842012-11-14 13:47:37 -0500778 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000779 kmem_cache_free(cachep, gl);
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000780 atomic_dec(&sdp->sd_glock_disposal);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000781 gl = tmp;
782 } else {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000783 hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]);
784 spin_unlock_bucket(hash);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000785 }
786
787 *glp = gl;
788
789 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000790}
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
Steven Whitehouse190562b2006-04-20 16:57:23 -0400801void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000802 struct gfs2_holder *gh)
803{
804 INIT_LIST_HEAD(&gh->gh_list);
805 gh->gh_gl = gl;
Fabian Frederickd29c0af2014-10-03 20:15:36 +0200806 gh->gh_ip = _RET_IP_;
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800807 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000808 gh->gh_state = state;
809 gh->gh_flags = flags;
810 gh->gh_error = 0;
811 gh->gh_iflags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000812 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
Steven Whitehouse190562b2006-04-20 16:57:23 -0400825void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000826{
827 gh->gh_state = state;
Steven Whitehouse579b78a2006-04-26 14:58:26 -0400828 gh->gh_flags = flags;
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000829 gh->gh_iflags = 0;
Fabian Frederickd29c0af2014-10-03 20:15:36 +0200830 gh->gh_ip = _RET_IP_;
Markus Elfring30badc92014-11-18 11:31:23 +0100831 put_pid(gh->gh_owner_pid);
Bob Peterson1a0eae82010-04-14 11:58:16 -0400832 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000833}
834
835/**
836 * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
837 * @gh: the holder structure
838 *
839 */
840
841void gfs2_holder_uninit(struct gfs2_holder *gh)
842{
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800843 put_pid(gh->gh_owner_pid);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000844 gfs2_glock_put(gh->gh_gl);
845 gh->gh_gl = NULL;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500846 gh->gh_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000847}
848
Steven Whitehousefe64d512009-05-19 10:01:18 +0100849/**
Bob Peterson07a79042012-08-09 12:48:44 -0500850 * gfs2_glock_wait - wait on a glock acquisition
851 * @gh: the glock holder
852 *
853 * Returns: 0 on success
854 */
855
856int gfs2_glock_wait(struct gfs2_holder *gh)
Steven Whitehousefee852e2007-01-17 15:33:23 +0000857{
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400858 unsigned long time1 = jiffies;
859
Steven Whitehousefee852e2007-01-17 15:33:23 +0000860 might_sleep();
NeilBrown74316202014-07-07 15:16:04 +1000861 wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400862 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);
Bob Peterson07a79042012-08-09 12:48:44 -0500867 return gh->gh_error;
Abhijith Dasd93cfa92007-06-11 08:22:32 +0100868}
869
David Teiglandb3b94fa2006-01-16 16:50:04 +0000870/**
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000871 * handle_callback - process a demote request
David Teiglandb3b94fa2006-01-16 16:50:04 +0000872 * @gl: the glock
873 * @state: the state the caller wants us to change to
874 *
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000875 * There are only two requests that we are going to see in actual
876 * practise: LM_ST_SHARED and LM_ST_UNLOCKED
David Teiglandb3b94fa2006-01-16 16:50:04 +0000877 */
878
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500879static void handle_callback(struct gfs2_glock *gl, unsigned int state,
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100880 unsigned long delay, bool remote)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000881{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500882 int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE;
883
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500884 set_bit(bit, &gl->gl_flags);
885 if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000886 gl->gl_demote_state = state;
887 gl->gl_demote_time = jiffies;
Josef Whiter26caee52007-07-23 10:02:40 +0100888 } else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
889 gl->gl_demote_state != state) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100890 gl->gl_demote_state = LM_ST_UNLOCKED;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000891 }
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500892 if (gl->gl_ops->go_callback)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100893 gl->gl_ops->go_callback(gl, remote);
Steven Whitehouse7bd8b2e2013-04-10 10:32:05 +0100894 trace_gfs2_demote_rq(gl, remote);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000895}
896
Steven Whitehouse6802e342008-05-21 17:03:22 +0100897void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
Robert Peterson7c52b162007-03-16 10:26:37 +0000898{
Joe Perches5e690692010-11-09 16:35:20 -0800899 struct va_format vaf;
Robert Peterson7c52b162007-03-16 10:26:37 +0000900 va_list args;
901
902 va_start(args, fmt);
Joe Perches5e690692010-11-09 16:35:20 -0800903
Steven Whitehouse6802e342008-05-21 17:03:22 +0100904 if (seq) {
Steven Whitehouse1bb49302012-06-11 13:26:50 +0100905 seq_vprintf(seq, fmt, args);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100906 } else {
Joe Perches5e690692010-11-09 16:35:20 -0800907 vaf.fmt = fmt;
908 vaf.va = &args;
909
Joe Perchesd77d1b52014-03-06 12:10:45 -0800910 pr_err("%pV", &vaf);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100911 }
Joe Perches5e690692010-11-09 16:35:20 -0800912
Robert Peterson7c52b162007-03-16 10:26:37 +0000913 va_end(args);
914}
915
David Teiglandb3b94fa2006-01-16 16:50:04 +0000916/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000917 * add_to_queue - Add a holder to the wait queue (but look for recursion)
918 * @gh: the holder structure to add
919 *
Steven Whitehouse6802e342008-05-21 17:03:22 +0100920 * 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 *
David Teiglandb3b94fa2006-01-16 16:50:04 +0000924 */
925
Steven Whitehouse6802e342008-05-21 17:03:22 +0100926static inline void add_to_queue(struct gfs2_holder *gh)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700927__releases(&gl->gl_spin)
928__acquires(&gl->gl_spin)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000929{
930 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100931 struct gfs2_sbd *sdp = gl->gl_sbd;
932 struct list_head *insert_pt = NULL;
933 struct gfs2_holder *gh2;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500934 int try_futile = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000935
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800936 BUG_ON(gh->gh_owner_pid == NULL);
Steven Whitehousefee852e2007-01-17 15:33:23 +0000937 if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
938 BUG();
Steven Whitehouse190562b2006-04-20 16:57:23 -0400939
Steven Whitehouse6802e342008-05-21 17:03:22 +0100940 if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
941 if (test_bit(GLF_LOCK, &gl->gl_flags))
Bob Petersone5dc76b2012-08-09 12:48:46 -0500942 try_futile = !may_grant(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100943 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
944 goto fail;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000945 }
946
Steven Whitehouse6802e342008-05-21 17:03:22 +0100947 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;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500951 if (try_futile &&
952 !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100953fail:
954 gh->gh_error = GLR_TRYFAILED;
955 gfs2_holder_wake(gh);
956 return;
957 }
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 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100963 set_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouseedae38a2011-01-31 09:38:12 +0000964 trace_gfs2_glock_queue(gh, 1);
Steven Whitehousea2457692012-01-20 10:38:36 +0000965 gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
966 gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100967 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);
974do_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);
Steven Whitehouse048bca22008-05-23 14:46:04 +0100978 if (sdp->sd_lockstruct.ls_ops->lm_cancel)
Steven Whitehousef057f6c2009-01-12 10:43:39 +0000979 sdp->sd_lockstruct.ls_ops->lm_cancel(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100980 spin_lock(&gl->gl_spin);
981 }
982 return;
983
984trap_recursive:
Fabian Frederickfc554ed2014-03-05 22:06:42 +0800985 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",
Steven Whitehouse6802e342008-05-21 17:03:22 +0100988 gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
Fabian Frederickfc554ed2014-03-05 22:06:42 +0800989 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",
Steven Whitehouse6802e342008-05-21 17:03:22 +0100992 gh->gh_gl->gl_name.ln_type, gh->gh_state);
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +0100993 gfs2_dump_glock(NULL, gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100994 BUG();
David Teiglandb3b94fa2006-01-16 16:50:04 +0000995}
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
1006int 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
Steven Whitehouse6802e342008-05-21 17:03:22 +01001012 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001013 return -EIO;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001014
Steven Whitehousef42ab082011-04-14 16:50:31 +01001015 if (test_bit(GLF_LRU, &gl->gl_flags))
1016 gfs2_glock_remove_from_lru(gl);
1017
David Teiglandb3b94fa2006-01-16 16:50:04 +00001018 spin_lock(&gl->gl_spin);
1019 add_to_queue(gh);
Bob Peterson01b172b2014-03-12 10:32:20 -04001020 if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) &&
1021 test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) {
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001022 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Bob Peterson01b172b2014-03-12 10:32:20 -04001023 gl->gl_lockref.count++;
1024 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1025 gl->gl_lockref.count--;
1026 }
Steven Whitehouse6802e342008-05-21 17:03:22 +01001027 run_queue(gl, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001028 spin_unlock(&gl->gl_spin);
1029
Steven Whitehouse6802e342008-05-21 17:03:22 +01001030 if (!(gh->gh_flags & GL_ASYNC))
1031 error = gfs2_glock_wait(gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001032
David Teiglandb3b94fa2006-01-16 16:50:04 +00001033 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
1043int gfs2_glock_poll(struct gfs2_holder *gh)
1044{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001045 return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001046}
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
1054void gfs2_glock_dq(struct gfs2_holder *gh)
1055{
1056 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001057 const struct gfs2_glock_operations *glops = gl->gl_ops;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001058 unsigned delay = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001059 int fast_path = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001060
Steven Whitehouse6802e342008-05-21 17:03:22 +01001061 spin_lock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001062 if (gh->gh_flags & GL_NOCACHE)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001063 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001064
David Teiglandb3b94fa2006-01-16 16:50:04 +00001065 list_del_init(&gh->gh_list);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001066 if (find_first_holder(gl) == NULL) {
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001067 if (glops->go_unlock) {
Steven Whitehouse6802e342008-05-21 17:03:22 +01001068 GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags));
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001069 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001070 glops->go_unlock(gh);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001071 spin_lock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001072 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001073 }
Steven Whitehouse6802e342008-05-21 17:03:22 +01001074 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;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001078 }
Bob Petersone7ccaf52015-06-12 13:15:54 -05001079 if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl) &&
1080 (glops->go_flags & GLOF_LRU))
Bob Peterson4abb6ad2012-08-09 12:48:43 -05001081 gfs2_glock_add_to_lru(gl);
1082
Steven Whitehouse63997772009-06-12 08:49:20 +01001083 trace_gfs2_glock_queue(gh, 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001084 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001085 if (likely(fast_path))
1086 return;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001087
1088 gfs2_glock_hold(gl);
1089 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001090 !test_bit(GLF_DEMOTE, &gl->gl_flags) &&
1091 gl->gl_name.ln_type == LM_TYPE_INODE)
1092 delay = gl->gl_hold_time;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001093 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1094 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001095}
1096
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001097void gfs2_glock_dq_wait(struct gfs2_holder *gh)
1098{
1099 struct gfs2_glock *gl = gh->gh_gl;
1100 gfs2_glock_dq(gh);
Bob Peterson81e1d452012-08-09 12:48:45 -05001101 might_sleep();
NeilBrown74316202014-07-07 15:16:04 +10001102 wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE);
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001103}
1104
David Teiglandb3b94fa2006-01-16 16:50:04 +00001105/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001106 * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
1107 * @gh: the holder structure
1108 *
1109 */
1110
1111void 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
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001123 * @flags: modifier flags for the acquisition
David Teiglandb3b94fa2006-01-16 16:50:04 +00001124 * @gh: the struct gfs2_holder
1125 *
1126 * Returns: errno
1127 */
1128
Steven Whitehousecd915492006-09-04 12:49:07 -04001129int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001130 const struct gfs2_glock_operations *glops,
1131 unsigned int state, int flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001132{
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
1152static int glock_compare(const void *arg_a, const void *arg_b)
1153{
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001154 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;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001158
1159 if (a->ln_number > b->ln_number)
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001160 return 1;
1161 if (a->ln_number < b->ln_number)
1162 return -1;
Steven Whitehouse1c0f4872007-01-22 12:10:39 -05001163 BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type);
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001164 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001165}
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
1176static 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 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001206 *
1207 * Returns: 0 on success (all glocks acquired),
1208 * errno on failure (no glocks acquired)
1209 */
1210
1211int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1212{
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001213 struct gfs2_holder *tmp[4];
1214 struct gfs2_holder **pph = tmp;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001215 int error = 0;
1216
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001217 switch(num_gh) {
1218 case 0:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001219 return 0;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001220 case 1:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001221 ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1222 return gfs2_glock_nq(ghs);
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001223 default:
1224 if (num_gh <= 4)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001225 break;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001226 pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS);
1227 if (!pph)
1228 return -ENOMEM;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001229 }
1230
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001231 error = nq_m_sync(num_gh, ghs, pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001232
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001233 if (pph != tmp)
1234 kfree(pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001235
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
1246void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1247{
Bob Petersonfa1bbde2011-03-10 11:41:57 -05001248 while (num_gh--)
1249 gfs2_glock_dq(&ghs[num_gh]);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001250}
1251
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001252void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
Steven Whitehouseda755fd2008-01-30 15:34:04 +00001253{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001254 unsigned long delay = 0;
1255 unsigned long holdtime;
1256 unsigned long now = jiffies;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001257
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001258 gfs2_glock_hold(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001259 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) {
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001262 if (time_before(now, holdtime))
1263 delay = holdtime - now;
1264 if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001265 delay = gl->gl_hold_time;
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001266 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001267
Steven Whitehouse6802e342008-05-21 17:03:22 +01001268 spin_lock(&gl->gl_spin);
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001269 handle_callback(gl, state, delay, true);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001270 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001271 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1272 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001273}
1274
1275/**
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001276 * 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
1286static 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
1305/**
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001306 * gfs2_glock_complete - Callback used by locking
1307 * @gl: Pointer to the glock
1308 * @ret: The return value from the dlm
David Teiglandb3b94fa2006-01-16 16:50:04 +00001309 *
Steven Whitehouse47a25382010-11-30 15:49:31 +00001310 * 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.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001312 */
1313
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001314void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001315{
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001316 struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001317
Steven Whitehouse47a25382010-11-30 15:49:31 +00001318 spin_lock(&gl->gl_spin);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001319 gl->gl_reply = ret;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001320
David Teiglande0c2a9a2012-01-09 17:18:05 -05001321 if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001322 if (gfs2_should_freeze(gl)) {
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001323 set_bit(GLF_FROZEN, &gl->gl_flags);
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001324 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001325 return;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001326 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001327 }
Steven Whitehouse47a25382010-11-30 15:49:31 +00001328
Steven Whitehousee66cf162013-10-15 15:18:08 +01001329 gl->gl_lockref.count++;
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001330 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001331 spin_unlock(&gl->gl_spin);
1332
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001333 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1334 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001335}
1336
Steven Whitehouse4506a512013-02-01 20:36:03 +00001337static 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
1366static 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);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001377 if (!spin_trylock(&gl->gl_spin)) {
Steven Whitehouse94a09a32014-06-23 14:43:32 +01001378add_back_to_lru:
Steven Whitehousee66cf162013-10-15 15:18:08 +01001379 list_add(&gl->gl_lru, &lru_list);
1380 atomic_inc(&lru_count);
1381 continue;
1382 }
Steven Whitehouse94a09a32014-06-23 14:43:32 +01001383 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
1384 spin_unlock(&gl->gl_spin);
1385 goto add_back_to_lru;
1386 }
Steven Whitehouse4506a512013-02-01 20:36:03 +00001387 clear_bit(GLF_LRU, &gl->gl_flags);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001388 gl->gl_lockref.count++;
Steven Whitehouse4506a512013-02-01 20:36:03 +00001389 if (demote_ok(gl))
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001390 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001391 WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
Steven Whitehouse4506a512013-02-01 20:36:03 +00001392 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
Steven Whitehousee66cf162013-10-15 15:18:08 +01001393 gl->gl_lockref.count--;
Steven Whitehouse4506a512013-02-01 20:36:03 +00001394 spin_unlock(&gl->gl_spin);
Steven Whitehouse94a09a32014-06-23 14:43:32 +01001395 cond_resched_lock(&lru_lock);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001396 }
1397}
1398
Steven Whitehouse2a005852012-12-14 12:28:30 +00001399/**
1400 * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote
1401 * @nr: The number of entries to scan
1402 *
Steven Whitehouse4506a512013-02-01 20:36:03 +00001403 * 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.
Steven Whitehouse2a005852012-12-14 12:28:30 +00001406 */
David Teiglandb3b94fa2006-01-16 16:50:04 +00001407
Dave Chinner1ab6c492013-08-28 10:18:09 +10001408static long gfs2_scan_glock_lru(int nr)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001409{
1410 struct gfs2_glock *gl;
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001411 LIST_HEAD(skipped);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001412 LIST_HEAD(dispose);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001413 long freed = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001414
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001415 spin_lock(&lru_lock);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001416 while ((nr-- >= 0) && !list_empty(&lru_list)) {
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001417 gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001418
1419 /* Test for being demotable */
Steven Whitehouse94a09a32014-06-23 14:43:32 +01001420 if (!test_bit(GLF_LOCK, &gl->gl_flags)) {
Steven Whitehouse4506a512013-02-01 20:36:03 +00001421 list_move(&gl->gl_lru, &dispose);
1422 atomic_dec(&lru_count);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001423 freed++;
Steven Whitehouse2163b1e2009-06-25 16:30:26 +01001424 continue;
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001425 }
Steven Whitehouse4506a512013-02-01 20:36:03 +00001426
1427 list_move(&gl->gl_lru, &skipped);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001428 }
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001429 list_splice(&skipped, &lru_list);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001430 if (!list_empty(&dispose))
1431 gfs2_dispose_glock_lru(&dispose);
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001432 spin_unlock(&lru_lock);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001433
1434 return freed;
Steven Whitehouse2a005852012-12-14 12:28:30 +00001435}
1436
Dave Chinner1ab6c492013-08-28 10:18:09 +10001437static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
1438 struct shrink_control *sc)
Steven Whitehouse2a005852012-12-14 12:28:30 +00001439{
Dave Chinner1ab6c492013-08-28 10:18:09 +10001440 if (!(sc->gfp_mask & __GFP_FS))
1441 return SHRINK_STOP;
1442 return gfs2_scan_glock_lru(sc->nr_to_scan);
1443}
Steven Whitehouse2a005852012-12-14 12:28:30 +00001444
Dave Chinner1ab6c492013-08-28 10:18:09 +10001445static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
1446 struct shrink_control *sc)
1447{
Glauber Costa55f841c2013-08-28 10:17:53 +10001448 return vfs_pressure_ratio(atomic_read(&lru_count));
David Teiglandb3b94fa2006-01-16 16:50:04 +00001449}
1450
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001451static struct shrinker glock_shrinker = {
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001452 .seeks = DEFAULT_SEEKS,
Dave Chinner1ab6c492013-08-28 10:18:09 +10001453 .count_objects = gfs2_glock_shrink_count,
1454 .scan_objects = gfs2_glock_shrink_scan,
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001455};
1456
David Teiglandb3b94fa2006-01-16 16:50:04 +00001457/**
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 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001463 */
1464
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001465static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp,
Steven Whitehouse37b2fa62006-09-08 13:35:56 -04001466 unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001467{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001468 struct gfs2_glock *gl;
1469 struct hlist_bl_head *head = &gl_hash_table[hash];
1470 struct hlist_bl_node *pos;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001471
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001472 rcu_read_lock();
1473 hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) {
Steven Whitehousee66cf162013-10-15 15:18:08 +01001474 if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref))
Steven Whitehouse24264432006-09-11 21:40:30 -04001475 examiner(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001476 }
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001477 rcu_read_unlock();
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001478 cond_resched();
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001479}
1480
1481static 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);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001487}
1488
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001489
1490/**
1491 * thaw_glock - thaw out a glock which has an unprocessed reply waiting
1492 * @gl: The glock to thaw
1493 *
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001494 */
1495
1496static void thaw_glock(struct gfs2_glock *gl)
1497{
1498 if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
Steven Whitehouse7286b312013-08-20 09:35:09 +01001499 goto out;
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001500 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehouse7286b312013-08-20 09:35:09 +01001501 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) {
1502out:
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001503 gfs2_glock_put(gl);
Steven Whitehouse7286b312013-08-20 09:35:09 +01001504 }
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001505}
1506
David Teiglandb3b94fa2006-01-16 16:50:04 +00001507/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001508 * 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
1513static void clear_glock(struct gfs2_glock *gl)
1514{
Steven Whitehousef42ab082011-04-14 16:50:31 +01001515 gfs2_glock_remove_from_lru(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001516
Steven Whitehouse6802e342008-05-21 17:03:22 +01001517 spin_lock(&gl->gl_spin);
Steven Whitehousec741c452010-09-29 14:20:52 +01001518 if (gl->gl_state != LM_ST_UNLOCKED)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001519 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001520 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001521 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1522 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001523}
1524
1525/**
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001526 * gfs2_glock_thaw - Thaw any frozen glocks
1527 * @sdp: The super block
1528 *
1529 */
1530
1531void gfs2_glock_thaw(struct gfs2_sbd *sdp)
1532{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001533 glock_hash_walk(thaw_glock, sdp);
1534}
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001535
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001536static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001537{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001538 spin_lock(&gl->gl_spin);
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001539 gfs2_dump_glock(seq, gl);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001540 spin_unlock(&gl->gl_spin);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001541}
1542
1543static void dump_glock_func(struct gfs2_glock *gl)
1544{
1545 dump_glock(NULL, gl);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001546}
1547
1548/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001549 * gfs2_gl_hash_clear - Empty out the glock hash table
1550 * @sdp: the filesystem
1551 * @wait: wait until it's all gone
1552 *
Steven Whitehouse1bdad602008-06-03 14:09:53 +01001553 * Called when unmounting the filesystem.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001554 */
1555
Steven Whitehousefefc03b2008-12-19 15:32:06 +00001556void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001557{
David Teiglandfb6791d2012-11-13 10:58:56 -05001558 set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
Bob Peterson222cb532013-04-25 12:49:17 -04001559 flush_workqueue(glock_workqueue);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001560 glock_hash_walk(clear_glock, sdp);
Steven Whitehouse8f052282010-01-29 15:21:27 +00001561 flush_workqueue(glock_workqueue);
1562 wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001563 glock_hash_walk(dump_glock_func, sdp);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001564}
1565
Steven Whitehouse813e0c42008-11-18 13:38:48 +00001566void 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
Steven Whitehouse6802e342008-05-21 17:03:22 +01001580static const char *state2str(unsigned state)
Robert Peterson04b933f2007-03-23 17:05:15 -05001581{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001582 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}
Robert Peterson04b933f2007-03-23 17:05:15 -05001594
Steven Whitehouse6802e342008-05-21 17:03:22 +01001595static 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)
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001605 *p++ = 'A';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001606 if (flags & LM_FLAG_PRIORITY)
1607 *p++ = 'p';
1608 if (flags & GL_ASYNC)
1609 *p++ = 'a';
1610 if (flags & GL_EXACT)
1611 *p++ = 'E';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001612 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;
Robert Peterson04b933f2007-03-23 17:05:15 -05001622}
1623
David Teiglandb3b94fa2006-01-16 16:50:04 +00001624/**
1625 * dump_holder - print information about a glock holder
Steven Whitehouse6802e342008-05-21 17:03:22 +01001626 * @seq: the seq_file struct
David Teiglandb3b94fa2006-01-16 16:50:04 +00001627 * @gh: the glock holder
1628 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001629 */
1630
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001631static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001632{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001633 struct task_struct *gh_owner = NULL;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001634 char flags_buf[32];
David Teiglandb3b94fa2006-01-16 16:50:04 +00001635
Tetsuo Handa0b3a2c92014-01-02 19:52:20 +09001636 rcu_read_lock();
Steven Whitehouse6802e342008-05-21 17:03:22 +01001637 if (gh->gh_owner_pid)
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -08001638 gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
Joe Perchescc181522010-11-05 16:12:36 -07001639 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);
Tetsuo Handa0b3a2c92014-01-02 19:52:20 +09001646 rcu_read_unlock();
David Teiglandb3b94fa2006-01-16 16:50:04 +00001647}
1648
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001649static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001650{
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001651 const unsigned long *gflags = &gl->gl_flags;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001652 char *p = buf;
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001653
Steven Whitehouse6802e342008-05-21 17:03:22 +01001654 if (test_bit(GLF_LOCK, gflags))
1655 *p++ = 'l';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001656 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';
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001670 if (test_bit(GLF_INITIAL, gflags))
Steven Whitehoused8348de2009-02-05 10:12:38 +00001671 *p++ = 'I';
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001672 if (test_bit(GLF_FROZEN, gflags))
1673 *p++ = 'F';
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001674 if (test_bit(GLF_QUEUED, gflags))
1675 *p++ = 'q';
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001676 if (test_bit(GLF_LRU, gflags))
1677 *p++ = 'L';
1678 if (gl->gl_object)
1679 *p++ = 'o';
Steven Whitehousea2457692012-01-20 10:38:36 +00001680 if (test_bit(GLF_BLOCKING, gflags))
1681 *p++ = 'b';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001682 *p = 0;
1683 return buf;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001684}
1685
1686/**
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001687 * gfs2_dump_glock - print information about a glock
Steven Whitehouse6802e342008-05-21 17:03:22 +01001688 * @seq: The seq_file struct
David Teiglandb3b94fa2006-01-16 16:50:04 +00001689 * @gl: the glock
Steven Whitehouse6802e342008-05-21 17:03:22 +01001690 *
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.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001700 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001701 */
1702
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001703void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001704{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001705 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];
David Teiglandb3b94fa2006-01-16 16:50:04 +00001709
Steven Whitehouse6802e342008-05-21 17:03:22 +01001710 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;
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001714 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",
Steven Whitehouse6802e342008-05-21 17:03:22 +01001715 state2str(gl->gl_state),
1716 gl->gl_name.ln_type,
1717 (unsigned long long)gl->gl_name.ln_number,
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001718 gflags2str(gflags_buf, gl),
Steven Whitehouse6802e342008-05-21 17:03:22 +01001719 state2str(gl->gl_target),
1720 state2str(gl->gl_demote_state), dtime,
Steven Whitehouse6802e342008-05-21 17:03:22 +01001721 atomic_read(&gl->gl_ail_count),
Steven Whitehousef42ab082011-04-14 16:50:31 +01001722 atomic_read(&gl->gl_revokes),
Steven Whitehousee66cf162013-10-15 15:18:08 +01001723 (int)gl->gl_lockref.count, gl->gl_hold_time);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001724
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001725 list_for_each_entry(gh, &gl->gl_holders, gh_list)
1726 dump_holder(seq, gh);
1727
Steven Whitehouse6802e342008-05-21 17:03:22 +01001728 if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001729 glops->go_dump(seq, gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001730}
1731
Steven Whitehousea2457692012-01-20 10:38:36 +00001732static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
1733{
1734 struct gfs2_glock *gl = iter_ptr;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001735
Steven Whitehousea2457692012-01-20 10:38:36 +00001736 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}
David Teiglandb3b94fa2006-01-16 16:50:04 +00001749
Steven Whitehousea2457692012-01-20 10:38:36 +00001750static 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
1764static 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
1777static 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;
1788
1789 seq_printf(seq, "%-10s %8s:", gfs2_gltype[index],
1790 (index == 0) ? "cpu": gfs2_stype[subindex]);
1791
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}
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001804
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001805int __init gfs2_glock_init(void)
1806{
1807 unsigned i;
1808 for(i = 0; i < GFS2_GL_HASH_SIZE; i++) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001809 INIT_HLIST_BL_HEAD(&gl_hash_table[i]);
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001810 }
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001811
Steven Whitehoused2115772010-11-03 19:58:53 +00001812 glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
Tejun Heo58a69cb2011-02-16 09:25:31 +01001813 WQ_HIGHPRI | WQ_FREEZABLE, 0);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001814 if (!glock_workqueue)
1815 return -ENOMEM;
Steven Whitehoused2115772010-11-03 19:58:53 +00001816 gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
Tejun Heo58a69cb2011-02-16 09:25:31 +01001817 WQ_MEM_RECLAIM | WQ_FREEZABLE,
Steven Whitehoused2115772010-11-03 19:58:53 +00001818 0);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001819 if (!gfs2_delete_workqueue) {
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001820 destroy_workqueue(glock_workqueue);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001821 return -ENOMEM;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001822 }
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001823
1824 register_shrinker(&glock_shrinker);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001825
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001826 return 0;
1827}
1828
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001829void gfs2_glock_exit(void)
1830{
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001831 unregister_shrinker(&glock_shrinker);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001832 destroy_workqueue(glock_workqueue);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001833 destroy_workqueue(gfs2_delete_workqueue);
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001834}
1835
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001836static 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
1842static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl)
1843{
Steven Whitehouse7e32d022011-03-15 08:32:14 +00001844 return hlist_bl_entry(rcu_dereference(gl->gl_list.next),
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001845 struct gfs2_glock, gl_list);
1846}
1847
Steven Whitehouse6802e342008-05-21 17:03:22 +01001848static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
Robert Peterson7c52b162007-03-16 10:26:37 +00001849{
Steven Whitehouse7b08fc62007-07-24 13:53:36 +01001850 struct gfs2_glock *gl;
1851
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001852 do {
1853 gl = gi->gl;
1854 if (gl) {
1855 gi->gl = glock_hash_next(gl);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001856 gi->nhash++;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001857 } else {
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001858 if (gi->hash >= GFS2_GL_HASH_SIZE) {
1859 rcu_read_unlock();
1860 return 1;
1861 }
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001862 gi->gl = glock_hash_chain(gi->hash);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001863 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001864 }
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);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001872 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001873 }
1874 /* Skip entries for other sb and dead entries */
Michal Nazarewicze3c42692013-11-12 13:30:05 +01001875 } while (gi->sdp != gi->gl->gl_sbd ||
1876 __lockref_is_dead(&gi->gl->gl_lockref));
Abhijith Dasa947e032007-08-21 09:57:29 -05001877
Robert Peterson7c52b162007-03-16 10:26:37 +00001878 return 0;
1879}
1880
Steven Whitehouse6802e342008-05-21 17:03:22 +01001881static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
Robert Peterson7c52b162007-03-16 10:26:37 +00001882{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001883 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001884 loff_t n = *pos;
1885
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001886 if (gi->last_pos <= *pos)
1887 n = gi->nhash + (*pos - gi->last_pos);
1888 else
1889 gi->hash = 0;
1890
1891 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001892 rcu_read_lock();
Robert Peterson7c52b162007-03-16 10:26:37 +00001893
Steven Whitehouse6802e342008-05-21 17:03:22 +01001894 do {
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001895 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001896 return NULL;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001897 } while (n--);
Robert Peterson7c52b162007-03-16 10:26:37 +00001898
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001899 gi->last_pos = *pos;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001900 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001901}
1902
Steven Whitehouse6802e342008-05-21 17:03:22 +01001903static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
Robert Peterson7c52b162007-03-16 10:26:37 +00001904 loff_t *pos)
1905{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001906 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001907
1908 (*pos)++;
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001909 gi->last_pos = *pos;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001910 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001911 return NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001912
Steven Whitehouse6802e342008-05-21 17:03:22 +01001913 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001914}
1915
Steven Whitehouse6802e342008-05-21 17:03:22 +01001916static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001917{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001918 struct gfs2_glock_iter *gi = seq->private;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001919
1920 if (gi->gl)
1921 rcu_read_unlock();
1922 gi->gl = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001923}
1924
Steven Whitehouse6802e342008-05-21 17:03:22 +01001925static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001926{
Steven Whitehouseac3beb62014-01-16 10:31:13 +00001927 dump_glock(seq, iter_ptr);
1928 return 0;
Robert Peterson7c52b162007-03-16 10:26:37 +00001929}
1930
Steven Whitehousea2457692012-01-20 10:38:36 +00001931static 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
1942static 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
1955static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
1956{
1957 preempt_enable();
1958}
1959
Denis Cheng4ef29002007-07-31 18:31:11 +08001960static const struct seq_operations gfs2_glock_seq_ops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00001961 .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
Steven Whitehousea2457692012-01-20 10:38:36 +00001967static 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
1974static 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
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01001981#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
1982
Steven Whitehousea2457692012-01-20 10:38:36 +00001983static int gfs2_glocks_open(struct inode *inode, struct file *file)
Robert Peterson7c52b162007-03-16 10:26:37 +00001984{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001985 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;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01001991 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01001992 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01001993 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001994 }
1995 return ret;
Robert Peterson7c52b162007-03-16 10:26:37 +00001996}
1997
Steven Whitehousea2457692012-01-20 10:38:36 +00001998static 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;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002006 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01002007 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002008 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehousea2457692012-01-20 10:38:36 +00002009 }
2010 return ret;
2011}
2012
2013static 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
2025static const struct file_operations gfs2_glocks_fops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00002026 .owner = THIS_MODULE,
Steven Whitehousea2457692012-01-20 10:38:36 +00002027 .open = gfs2_glocks_open,
2028 .read = seq_read,
2029 .llseek = seq_lseek,
2030 .release = seq_release_private,
2031};
2032
2033static const struct file_operations gfs2_glstats_fops = {
2034 .owner = THIS_MODULE,
2035 .open = gfs2_glstats_open,
2036 .read = seq_read,
2037 .llseek = seq_lseek,
2038 .release = seq_release_private,
2039};
2040
2041static const struct file_operations gfs2_sbstats_fops = {
2042 .owner = THIS_MODULE,
2043 .open = gfs2_sbstats_open,
Robert Peterson7c52b162007-03-16 10:26:37 +00002044 .read = seq_read,
2045 .llseek = seq_lseek,
Steven Whitehouse6802e342008-05-21 17:03:22 +01002046 .release = seq_release_private,
Robert Peterson7c52b162007-03-16 10:26:37 +00002047};
2048
2049int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
2050{
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002051 struct dentry *dent;
Steven Whitehousea2457692012-01-20 10:38:36 +00002052
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002053 dent = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
2054 if (IS_ERR_OR_NULL(dent))
Steven Whitehousea2457692012-01-20 10:38:36 +00002055 goto fail;
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002056 sdp->debugfs_dir = dent;
Steven Whitehousea2457692012-01-20 10:38:36 +00002057
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002058 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))
Steven Whitehousea2457692012-01-20 10:38:36 +00002063 goto fail;
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002064 sdp->debugfs_dentry_glocks = dent;
2065
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))
2071 goto fail;
2072 sdp->debugfs_dentry_glstats = dent;
2073
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))
2079 goto fail;
2080 sdp->debugfs_dentry_sbstats = dent;
Robert Peterson7c52b162007-03-16 10:26:37 +00002081
2082 return 0;
Steven Whitehousea2457692012-01-20 10:38:36 +00002083fail:
2084 gfs2_delete_debugfs_file(sdp);
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002085 return dent ? PTR_ERR(dent) : -ENOMEM;
Robert Peterson7c52b162007-03-16 10:26:37 +00002086}
2087
2088void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
2089{
Steven Whitehousea2457692012-01-20 10:38:36 +00002090 if (sdp->debugfs_dir) {
Robert Peterson5f882092007-04-18 11:41:11 -05002091 if (sdp->debugfs_dentry_glocks) {
2092 debugfs_remove(sdp->debugfs_dentry_glocks);
2093 sdp->debugfs_dentry_glocks = NULL;
2094 }
Steven Whitehousea2457692012-01-20 10:38:36 +00002095 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 }
Robert Peterson5f882092007-04-18 11:41:11 -05002103 debugfs_remove(sdp->debugfs_dir);
2104 sdp->debugfs_dir = NULL;
2105 }
Robert Peterson7c52b162007-03-16 10:26:37 +00002106}
2107
2108int gfs2_register_debugfs(void)
2109{
2110 gfs2_root = debugfs_create_dir("gfs2", NULL);
Chengyu Song7b4ddfa2015-03-24 09:37:53 -05002111 if (IS_ERR(gfs2_root))
2112 return PTR_ERR(gfs2_root);
Robert Peterson7c52b162007-03-16 10:26:37 +00002113 return gfs2_root ? 0 : -ENOMEM;
2114}
2115
2116void gfs2_unregister_debugfs(void)
2117{
2118 debugfs_remove(gfs2_root);
Robert Peterson5f882092007-04-18 11:41:11 -05002119 gfs2_root = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00002120}