blob: c8420f7e4db604da3663da61c5ae4556b6439783 [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
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000013#include <linux/buffer_head.h>
14#include <linux/delay.h>
15#include <linux/sort.h>
16#include <linux/jhash.h>
Steven Whitehoused0dc80d2006-03-29 14:36:49 -050017#include <linux/kallsyms.h>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050018#include <linux/gfs2_ondisk.h>
Steven Whitehouse24264432006-09-11 21:40:30 -040019#include <linux/list.h>
Steven Whitehousefee852e2007-01-17 15:33:23 +000020#include <linux/wait.h>
akpm@linux-foundation.org95d97b72007-03-05 23:10:39 -080021#include <linux/module.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000022#include <asm/uaccess.h>
Robert Peterson7c52b162007-03-16 10:26:37 +000023#include <linux/seq_file.h>
24#include <linux/debugfs.h>
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +010025#include <linux/kthread.h>
26#include <linux/freezer.h>
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050027#include <linux/workqueue.h>
28#include <linux/jiffies.h>
Steven Whitehousebc015cb2011-01-19 09:30:01 +000029#include <linux/rcupdate.h>
30#include <linux/rculist_bl.h>
31#include <linux/bit_spinlock.h>
Steven Whitehousea2457692012-01-20 10:38:36 +000032#include <linux/percpu.h>
Steven Whitehouse4506a5192013-02-01 20:36:03 +000033#include <linux/list_sort.h>
Steven Whitehousee66cf162013-10-15 15:18:08 +010034#include <linux/lockref.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000035
36#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050037#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000038#include "glock.h"
39#include "glops.h"
40#include "inode.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000041#include "lops.h"
42#include "meta_io.h"
43#include "quota.h"
44#include "super.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050045#include "util.h"
Steven Whitehouse813e0c42008-11-18 13:38:48 +000046#include "bmap.h"
Steven Whitehouse63997772009-06-12 08:49:20 +010047#define CREATE_TRACE_POINTS
48#include "trace_gfs2.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000049
Steven Whitehouse6802e342008-05-21 17:03:22 +010050struct gfs2_glock_iter {
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +010051 int hash; /* hash bucket index */
52 unsigned nhash; /* Index within current bucket */
53 struct gfs2_sbd *sdp; /* incore superblock */
54 struct gfs2_glock *gl; /* current glock struct */
55 loff_t last_pos; /* last position */
Robert Peterson7c52b162007-03-16 10:26:37 +000056};
57
David Teiglandb3b94fa2006-01-16 16:50:04 +000058typedef void (*glock_examiner) (struct gfs2_glock * gl);
59
Steven Whitehouse6802e342008-05-21 17:03:22 +010060static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050061
Robert Peterson7c52b162007-03-16 10:26:37 +000062static struct dentry *gfs2_root;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050063static struct workqueue_struct *glock_workqueue;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -050064struct workqueue_struct *gfs2_delete_workqueue;
Steven Whitehouse97cc10252008-11-20 13:39:47 +000065static LIST_HEAD(lru_list);
66static atomic_t lru_count = ATOMIC_INIT(0);
Julia Lawalleb8374e2008-12-25 15:35:27 +010067static DEFINE_SPINLOCK(lru_lock);
Adrian Bunk08bc2db2006-04-28 10:59:12 -040068
Steven Whitehouseb6397892006-09-12 10:10:01 -040069#define GFS2_GL_HASH_SHIFT 15
Steven Whitehouse087efdd2006-09-09 16:59:11 -040070#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
71#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
72
Steven Whitehousebc015cb2011-01-19 09:30:01 +000073static struct hlist_bl_head gl_hash_table[GFS2_GL_HASH_SIZE];
Robert Peterson04b933f2007-03-23 17:05:15 -050074static struct dentry *gfs2_root;
Steven Whitehouse087efdd2006-09-09 16:59:11 -040075
David Teiglandb3b94fa2006-01-16 16:50:04 +000076/**
David Teiglandb3b94fa2006-01-16 16:50:04 +000077 * gl_hash() - Turn glock number into hash bucket number
78 * @lock: The glock number
79 *
80 * Returns: The number of the corresponding hash bucket
81 */
82
Steven Whitehouseb8547852006-09-07 13:12:27 -040083static unsigned int gl_hash(const struct gfs2_sbd *sdp,
84 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +000085{
86 unsigned int h;
87
Steven Whitehousecd915492006-09-04 12:49:07 -040088 h = jhash(&name->ln_number, sizeof(u64), 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +000089 h = jhash(&name->ln_type, sizeof(unsigned int), h);
Steven Whitehouseb8547852006-09-07 13:12:27 -040090 h = jhash(&sdp, sizeof(struct gfs2_sbd *), h);
David Teiglandb3b94fa2006-01-16 16:50:04 +000091 h &= GFS2_GL_HASH_MASK;
92
93 return h;
94}
95
Steven Whitehousebc015cb2011-01-19 09:30:01 +000096static inline void spin_lock_bucket(unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +000097{
Christoph Hellwig1879fd62011-04-25 14:01:36 -040098 hlist_bl_lock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +000099}
David Teiglandb3b94fa2006-01-16 16:50:04 +0000100
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000101static inline void spin_unlock_bucket(unsigned int hash)
102{
Christoph Hellwig1879fd62011-04-25 14:01:36 -0400103 hlist_bl_unlock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000104}
105
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000106static void gfs2_glock_dealloc(struct rcu_head *rcu)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000107{
108 struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000109
David Teiglanddba2d702012-11-14 13:46:53 -0500110 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000111 kmem_cache_free(gfs2_glock_aspace_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500112 } else {
David Teigland4e2f8842012-11-14 13:47:37 -0500113 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000114 kmem_cache_free(gfs2_glock_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500115 }
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000116}
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000117
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000118void gfs2_glock_free(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000119{
120 struct gfs2_sbd *sdp = gl->gl_sbd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000121
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000122 call_rcu(&gl->gl_rcu, gfs2_glock_dealloc);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000123 if (atomic_dec_and_test(&sdp->sd_glock_disposal))
124 wake_up(&sdp->sd_glock_wait);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000125}
126
127/**
128 * gfs2_glock_hold() - increment reference count on glock
129 * @gl: The glock to hold
130 *
131 */
132
Steven Whitehousee66cf162013-10-15 15:18:08 +0100133static void gfs2_glock_hold(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000134{
Steven Whitehousee66cf162013-10-15 15:18:08 +0100135 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
136 lockref_get(&gl->gl_lockref);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000137}
138
139/**
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500140 * demote_ok - Check to see if it's ok to unlock a glock
141 * @gl: the glock
142 *
143 * Returns: 1 if it's ok
144 */
145
146static int demote_ok(const struct gfs2_glock *gl)
147{
148 const struct gfs2_glock_operations *glops = gl->gl_ops;
149
150 if (gl->gl_state == LM_ST_UNLOCKED)
151 return 0;
Steven Whitehousef42ab082011-04-14 16:50:31 +0100152 if (!list_empty(&gl->gl_holders))
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500153 return 0;
154 if (glops->go_demote_ok)
155 return glops->go_demote_ok(gl);
156 return 1;
157}
158
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000159
Steven Whitehouse29687a22011-03-30 16:33:25 +0100160void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
161{
162 spin_lock(&lru_lock);
163
164 if (!list_empty(&gl->gl_lru))
165 list_del_init(&gl->gl_lru);
166 else
167 atomic_inc(&lru_count);
168
169 list_add_tail(&gl->gl_lru, &lru_list);
Steven Whitehouse627c10b2011-04-14 14:09:52 +0100170 set_bit(GLF_LRU, &gl->gl_flags);
Steven Whitehouse29687a22011-03-30 16:33:25 +0100171 spin_unlock(&lru_lock);
172}
173
Steven Whitehouse4043b882012-01-16 15:46:21 +0000174static void __gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
Steven Whitehousef42ab082011-04-14 16:50:31 +0100175{
Steven Whitehousef42ab082011-04-14 16:50:31 +0100176 if (!list_empty(&gl->gl_lru)) {
177 list_del_init(&gl->gl_lru);
178 atomic_dec(&lru_count);
179 clear_bit(GLF_LRU, &gl->gl_flags);
180 }
Steven Whitehouse4043b882012-01-16 15:46:21 +0000181}
182
183static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
184{
185 spin_lock(&lru_lock);
186 __gfs2_glock_remove_from_lru(gl);
Steven Whitehousef42ab082011-04-14 16:50:31 +0100187 spin_unlock(&lru_lock);
188}
189
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500190/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000191 * gfs2_glock_put() - Decrement reference count on glock
192 * @gl: The glock to put
193 *
194 */
195
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000196void gfs2_glock_put(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000197{
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000198 struct gfs2_sbd *sdp = gl->gl_sbd;
199 struct address_space *mapping = gfs2_glock2aspace(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000200
Steven Whitehousee66cf162013-10-15 15:18:08 +0100201 if (lockref_put_or_lock(&gl->gl_lockref))
202 return;
203
204 lockref_mark_dead(&gl->gl_lockref);
205
206 spin_lock(&lru_lock);
207 __gfs2_glock_remove_from_lru(gl);
208 spin_unlock(&lru_lock);
209 spin_unlock(&gl->gl_lockref.lock);
210 spin_lock_bucket(gl->gl_hash);
211 hlist_bl_del_rcu(&gl->gl_list);
212 spin_unlock_bucket(gl->gl_hash);
213 GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
214 GLOCK_BUG_ON(gl, mapping && mapping->nrpages);
215 trace_gfs2_glock_put(gl);
216 sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000217}
218
219/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000220 * search_bucket() - Find struct gfs2_glock by lock number
221 * @bucket: the bucket to search
222 * @name: The lock name
223 *
224 * Returns: NULL, or the struct gfs2_glock with the requested number
225 */
226
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400227static struct gfs2_glock *search_bucket(unsigned int hash,
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400228 const struct gfs2_sbd *sdp,
Steven Whitehoused6a53722006-08-30 11:16:23 -0400229 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000230{
231 struct gfs2_glock *gl;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000232 struct hlist_bl_node *h;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000233
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000234 hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000235 if (!lm_name_equal(&gl->gl_name, name))
236 continue;
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400237 if (gl->gl_sbd != sdp)
238 continue;
Steven Whitehousee66cf162013-10-15 15:18:08 +0100239 if (lockref_get_not_dead(&gl->gl_lockref))
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000240 return gl;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000241 }
242
243 return NULL;
244}
245
246/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100247 * may_grant - check if its ok to grant a new lock
248 * @gl: The glock
249 * @gh: The lock request which we wish to grant
250 *
251 * Returns: true if its ok to grant the lock
252 */
253
254static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh)
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500255{
Steven Whitehouse6802e342008-05-21 17:03:22 +0100256 const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list);
257 if ((gh->gh_state == LM_ST_EXCLUSIVE ||
258 gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head)
259 return 0;
260 if (gl->gl_state == gh->gh_state)
261 return 1;
262 if (gh->gh_flags & GL_EXACT)
263 return 0;
Steven Whitehouse209806a2008-07-07 10:07:28 +0100264 if (gl->gl_state == LM_ST_EXCLUSIVE) {
265 if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED)
266 return 1;
267 if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED)
268 return 1;
269 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100270 if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY))
271 return 1;
272 return 0;
273}
274
275static void gfs2_holder_wake(struct gfs2_holder *gh)
276{
277 clear_bit(HIF_WAIT, &gh->gh_iflags);
278 smp_mb__after_clear_bit();
279 wake_up_bit(&gh->gh_iflags, HIF_WAIT);
280}
281
282/**
Steven Whitehoused5341a92010-07-23 14:05:51 +0100283 * do_error - Something unexpected has happened during a lock request
284 *
285 */
286
287static inline void do_error(struct gfs2_glock *gl, const int ret)
288{
289 struct gfs2_holder *gh, *tmp;
290
291 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
292 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
293 continue;
294 if (ret & LM_OUT_ERROR)
295 gh->gh_error = -EIO;
296 else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
297 gh->gh_error = GLR_TRYFAILED;
298 else
299 continue;
300 list_del_init(&gh->gh_list);
301 trace_gfs2_glock_queue(gh, 0);
302 gfs2_holder_wake(gh);
303 }
304}
305
306/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100307 * do_promote - promote as many requests as possible on the current queue
308 * @gl: The glock
309 *
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000310 * Returns: 1 if there is a blocked holder at the head of the list, or 2
311 * if a type specific operation is underway.
Steven Whitehouse6802e342008-05-21 17:03:22 +0100312 */
313
314static int do_promote(struct gfs2_glock *gl)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700315__releases(&gl->gl_spin)
316__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100317{
318 const struct gfs2_glock_operations *glops = gl->gl_ops;
319 struct gfs2_holder *gh, *tmp;
320 int ret;
321
322restart:
323 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
324 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
325 continue;
326 if (may_grant(gl, gh)) {
327 if (gh->gh_list.prev == &gl->gl_holders &&
328 glops->go_lock) {
329 spin_unlock(&gl->gl_spin);
330 /* FIXME: eliminate this eventually */
331 ret = glops->go_lock(gh);
332 spin_lock(&gl->gl_spin);
333 if (ret) {
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000334 if (ret == 1)
335 return 2;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100336 gh->gh_error = ret;
337 list_del_init(&gh->gh_list);
Steven Whitehouse63997772009-06-12 08:49:20 +0100338 trace_gfs2_glock_queue(gh, 0);
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, 1);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100344 gfs2_holder_wake(gh);
345 goto restart;
346 }
347 set_bit(HIF_HOLDER, &gh->gh_iflags);
Steven Whitehouse63997772009-06-12 08:49:20 +0100348 trace_gfs2_promote(gh, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100349 gfs2_holder_wake(gh);
350 continue;
351 }
352 if (gh->gh_list.prev == &gl->gl_holders)
353 return 1;
Steven Whitehoused5341a92010-07-23 14:05:51 +0100354 do_error(gl, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100355 break;
356 }
357 return 0;
358}
359
360/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100361 * find_first_waiter - find the first gh that's waiting for the glock
362 * @gl: the glock
363 */
364
365static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
366{
367 struct gfs2_holder *gh;
368
369 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
370 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
371 return gh;
372 }
373 return NULL;
374}
375
376/**
377 * state_change - record that the glock is now in a different state
378 * @gl: the glock
379 * @new_state the new state
380 *
381 */
382
383static void state_change(struct gfs2_glock *gl, unsigned int new_state)
384{
385 int held1, held2;
386
387 held1 = (gl->gl_state != LM_ST_UNLOCKED);
388 held2 = (new_state != LM_ST_UNLOCKED);
389
390 if (held1 != held2) {
Steven Whitehousee66cf162013-10-15 15:18:08 +0100391 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
Steven Whitehouse6802e342008-05-21 17:03:22 +0100392 if (held2)
Steven Whitehousee66cf162013-10-15 15:18:08 +0100393 gl->gl_lockref.count++;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100394 else
Steven Whitehousee66cf162013-10-15 15:18:08 +0100395 gl->gl_lockref.count--;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100396 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100397 if (held1 && held2 && list_empty(&gl->gl_holders))
398 clear_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100399
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400400 if (new_state != gl->gl_target)
401 /* shorten our minimum hold time */
402 gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
403 GL_GLOCK_MIN_HOLD);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100404 gl->gl_state = new_state;
405 gl->gl_tchange = jiffies;
406}
407
408static void gfs2_demote_wake(struct gfs2_glock *gl)
409{
410 gl->gl_demote_state = LM_ST_EXCLUSIVE;
411 clear_bit(GLF_DEMOTE, &gl->gl_flags);
412 smp_mb__after_clear_bit();
413 wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
414}
415
416/**
417 * finish_xmote - The DLM has replied to one of our lock requests
418 * @gl: The glock
419 * @ret: The status from the DLM
420 *
421 */
422
423static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
424{
425 const struct gfs2_glock_operations *glops = gl->gl_ops;
426 struct gfs2_holder *gh;
427 unsigned state = ret & LM_OUT_ST_MASK;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000428 int rv;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500429
430 spin_lock(&gl->gl_spin);
Steven Whitehouse63997772009-06-12 08:49:20 +0100431 trace_gfs2_glock_state_change(gl, state);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100432 state_change(gl, state);
433 gh = find_first_waiter(gl);
434
435 /* Demote to UN request arrived during demote to SH or DF */
436 if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
437 state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
438 gl->gl_target = LM_ST_UNLOCKED;
439
440 /* Check for state != intended state */
441 if (unlikely(state != gl->gl_target)) {
442 if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
443 /* move to back of queue and try next entry */
444 if (ret & LM_OUT_CANCELED) {
445 if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
446 list_move_tail(&gh->gh_list, &gl->gl_holders);
447 gh = find_first_waiter(gl);
448 gl->gl_target = gh->gh_state;
449 goto retry;
450 }
451 /* Some error or failed "try lock" - report it */
452 if ((ret & LM_OUT_ERROR) ||
453 (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
454 gl->gl_target = gl->gl_state;
455 do_error(gl, ret);
456 goto out;
457 }
458 }
459 switch(state) {
460 /* Unlocked due to conversion deadlock, try again */
461 case LM_ST_UNLOCKED:
462retry:
463 do_xmote(gl, gh, gl->gl_target);
464 break;
465 /* Conversion fails, unlock and try again */
466 case LM_ST_SHARED:
467 case LM_ST_DEFERRED:
468 do_xmote(gl, gh, LM_ST_UNLOCKED);
469 break;
470 default: /* Everything else */
471 printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state);
472 GLOCK_BUG_ON(gl, 1);
473 }
474 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100475 return;
476 }
477
478 /* Fast path - we got what we asked for */
479 if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
480 gfs2_demote_wake(gl);
481 if (state != LM_ST_UNLOCKED) {
482 if (glops->go_xmote_bh) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100483 spin_unlock(&gl->gl_spin);
484 rv = glops->go_xmote_bh(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100485 spin_lock(&gl->gl_spin);
486 if (rv) {
487 do_error(gl, rv);
488 goto out;
489 }
490 }
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000491 rv = do_promote(gl);
492 if (rv == 2)
493 goto out_locked;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100494 }
495out:
496 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000497out_locked:
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500498 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500499}
500
Steven Whitehouse6802e342008-05-21 17:03:22 +0100501/**
502 * do_xmote - Calls the DLM to change the state of a lock
503 * @gl: The lock state
504 * @gh: The holder (only for promotes)
505 * @target: The target lock state
506 *
507 */
508
509static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700510__releases(&gl->gl_spin)
511__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100512{
513 const struct gfs2_glock_operations *glops = gl->gl_ops;
514 struct gfs2_sbd *sdp = gl->gl_sbd;
515 unsigned int lck_flags = gh ? gh->gh_flags : 0;
516 int ret;
517
518 lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
519 LM_FLAG_PRIORITY);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000520 GLOCK_BUG_ON(gl, gl->gl_state == target);
521 GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100522 if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
523 glops->go_inval) {
524 set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
525 do_error(gl, 0); /* Fail queued try locks */
526 }
Steven Whitehouse47a25382010-11-30 15:49:31 +0000527 gl->gl_req = target;
Steven Whitehousea2457692012-01-20 10:38:36 +0000528 set_bit(GLF_BLOCKING, &gl->gl_flags);
529 if ((gl->gl_req == LM_ST_UNLOCKED) ||
530 (gl->gl_state == LM_ST_EXCLUSIVE) ||
531 (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
532 clear_bit(GLF_BLOCKING, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100533 spin_unlock(&gl->gl_spin);
Bob Peterson06dfc302012-10-24 14:41:05 -0400534 if (glops->go_sync)
535 glops->go_sync(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100536 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
537 glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
538 clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
539
540 gfs2_glock_hold(gl);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000541 if (sdp->sd_lockstruct.ls_ops->lm_lock) {
542 /* lock_dlm */
543 ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
David Teiglanddba2d702012-11-14 13:46:53 -0500544 if (ret) {
545 printk(KERN_ERR "GFS2: lm_lock ret %d\n", ret);
546 GLOCK_BUG_ON(gl, 1);
547 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000548 } else { /* lock_nolock */
549 finish_xmote(gl, target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100550 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
551 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100552 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000553
Steven Whitehouse6802e342008-05-21 17:03:22 +0100554 spin_lock(&gl->gl_spin);
555}
556
557/**
558 * find_first_holder - find the first "holder" gh
559 * @gl: the glock
560 */
561
562static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
563{
564 struct gfs2_holder *gh;
565
566 if (!list_empty(&gl->gl_holders)) {
567 gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
568 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
569 return gh;
570 }
571 return NULL;
572}
573
574/**
575 * run_queue - do all outstanding tasks related to a glock
576 * @gl: The glock in question
577 * @nonblock: True if we must not block in run_queue
578 *
579 */
580
581static void run_queue(struct gfs2_glock *gl, const int nonblock)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700582__releases(&gl->gl_spin)
583__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100584{
585 struct gfs2_holder *gh = NULL;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000586 int ret;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100587
588 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
589 return;
590
591 GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));
592
593 if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
594 gl->gl_demote_state != gl->gl_state) {
595 if (find_first_holder(gl))
Steven Whitehoused8348de2009-02-05 10:12:38 +0000596 goto out_unlock;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100597 if (nonblock)
598 goto out_sched;
599 set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100600 GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100601 gl->gl_target = gl->gl_demote_state;
602 } else {
603 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
604 gfs2_demote_wake(gl);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000605 ret = do_promote(gl);
606 if (ret == 0)
Steven Whitehoused8348de2009-02-05 10:12:38 +0000607 goto out_unlock;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000608 if (ret == 2)
Steven Whitehousea228df62009-04-07 14:01:34 +0100609 goto out;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100610 gh = find_first_waiter(gl);
611 gl->gl_target = gh->gh_state;
612 if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
613 do_error(gl, 0); /* Fail queued try locks */
614 }
615 do_xmote(gl, gh, gl->gl_target);
Steven Whitehousea228df62009-04-07 14:01:34 +0100616out:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100617 return;
618
619out_sched:
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100620 clear_bit(GLF_LOCK, &gl->gl_flags);
621 smp_mb__after_clear_bit();
Steven Whitehousee66cf162013-10-15 15:18:08 +0100622 gl->gl_lockref.count++;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100623 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
Steven Whitehousee66cf162013-10-15 15:18:08 +0100624 gl->gl_lockref.count--;
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100625 return;
626
Steven Whitehoused8348de2009-02-05 10:12:38 +0000627out_unlock:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100628 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100629 smp_mb__after_clear_bit();
630 return;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100631}
632
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500633static void delete_work_func(struct work_struct *work)
634{
635 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete);
636 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000637 struct gfs2_inode *ip;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500638 struct inode *inode;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000639 u64 no_addr = gl->gl_name.ln_number;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500640
Steven Whitehouse044b9412010-11-03 20:01:07 +0000641 ip = gl->gl_object;
642 /* Note: Unsafe to dereference ip as we don't hold right refs/locks */
643
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500644 if (ip)
Steven Whitehouse4667a0e2011-04-18 14:18:09 +0100645 inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1);
Steven Whitehouse044b9412010-11-03 20:01:07 +0000646 else
647 inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED);
648 if (inode && !IS_ERR(inode)) {
649 d_prune_aliases(inode);
650 iput(inode);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500651 }
652 gfs2_glock_put(gl);
653}
654
Steven Whitehouse6802e342008-05-21 17:03:22 +0100655static void glock_work_func(struct work_struct *work)
656{
657 unsigned long delay = 0;
658 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000659 int drop_ref = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100660
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000661 if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100662 finish_xmote(gl, gl->gl_reply);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000663 drop_ref = 1;
664 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100665 spin_lock(&gl->gl_spin);
Bob Petersonf90e5b52011-05-24 10:44:42 -0400666 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100667 gl->gl_state != LM_ST_UNLOCKED &&
668 gl->gl_demote_state != LM_ST_EXCLUSIVE) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100669 unsigned long holdtime, now = jiffies;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400670
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400671 holdtime = gl->gl_tchange + gl->gl_hold_time;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100672 if (time_before(now, holdtime))
673 delay = holdtime - now;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400674
675 if (!delay) {
676 clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
677 set_bit(GLF_DEMOTE, &gl->gl_flags);
678 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100679 }
680 run_queue(gl, 0);
681 spin_unlock(&gl->gl_spin);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400682 if (!delay)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100683 gfs2_glock_put(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400684 else {
685 if (gl->gl_name.ln_type != LM_TYPE_INODE)
686 delay = 0;
687 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
688 gfs2_glock_put(gl);
689 }
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000690 if (drop_ref)
691 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100692}
693
David Teiglandb3b94fa2006-01-16 16:50:04 +0000694/**
695 * gfs2_glock_get() - Get a glock, or create one if one doesn't exist
696 * @sdp: The GFS2 superblock
697 * @number: the lock number
698 * @glops: The glock_operations to use
699 * @create: If 0, don't create the glock if it doesn't exist
700 * @glp: the glock is returned here
701 *
702 * This does not lock a glock, just finds/creates structures for one.
703 *
704 * Returns: errno
705 */
706
Steven Whitehousecd915492006-09-04 12:49:07 -0400707int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400708 const struct gfs2_glock_operations *glops, int create,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000709 struct gfs2_glock **glp)
710{
Steven Whitehouse009d8512009-12-08 12:12:13 +0000711 struct super_block *s = sdp->sd_vfs;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400712 struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type };
David Teiglandb3b94fa2006-01-16 16:50:04 +0000713 struct gfs2_glock *gl, *tmp;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400714 unsigned int hash = gl_hash(sdp, &name);
Steven Whitehouse009d8512009-12-08 12:12:13 +0000715 struct address_space *mapping;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000716 struct kmem_cache *cachep;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000717
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000718 rcu_read_lock();
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400719 gl = search_bucket(hash, sdp, &name);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000720 rcu_read_unlock();
David Teiglandb3b94fa2006-01-16 16:50:04 +0000721
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000722 *glp = gl;
723 if (gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000724 return 0;
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000725 if (!create)
726 return -ENOENT;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000727
Steven Whitehouse009d8512009-12-08 12:12:13 +0000728 if (glops->go_flags & GLOF_ASPACE)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000729 cachep = gfs2_glock_aspace_cachep;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000730 else
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000731 cachep = gfs2_glock_cachep;
732 gl = kmem_cache_alloc(cachep, GFP_KERNEL);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000733 if (!gl)
734 return -ENOMEM;
735
David Teiglanddba2d702012-11-14 13:46:53 -0500736 memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
David Teiglanddba2d702012-11-14 13:46:53 -0500737
738 if (glops->go_flags & GLOF_LVB) {
David Teigland4e2f8842012-11-14 13:47:37 -0500739 gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_KERNEL);
740 if (!gl->gl_lksb.sb_lvbptr) {
David Teiglanddba2d702012-11-14 13:46:53 -0500741 kmem_cache_free(cachep, gl);
742 return -ENOMEM;
743 }
David Teiglanddba2d702012-11-14 13:46:53 -0500744 }
745
Steven Whitehouse8f052282010-01-29 15:21:27 +0000746 atomic_inc(&sdp->sd_glock_disposal);
Steven Whitehousea2457692012-01-20 10:38:36 +0000747 gl->gl_sbd = sdp;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400748 gl->gl_flags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000749 gl->gl_name = name;
Steven Whitehousee66cf162013-10-15 15:18:08 +0100750 gl->gl_lockref.count = 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000751 gl->gl_state = LM_ST_UNLOCKED;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100752 gl->gl_target = LM_ST_UNLOCKED;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500753 gl->gl_demote_state = LM_ST_EXCLUSIVE;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400754 gl->gl_hash = hash;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000755 gl->gl_ops = glops;
Steven Whitehousea2457692012-01-20 10:38:36 +0000756 gl->gl_dstamp = ktime_set(0, 0);
757 preempt_disable();
758 /* We use the global stats to estimate the initial per-glock stats */
759 gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type];
760 preempt_enable();
761 gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0;
762 gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500763 gl->gl_tchange = jiffies;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400764 gl->gl_object = NULL;
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400765 gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500766 INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500767 INIT_WORK(&gl->gl_delete, delete_work_func);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000768
Steven Whitehouse009d8512009-12-08 12:12:13 +0000769 mapping = gfs2_glock2aspace(gl);
770 if (mapping) {
771 mapping->a_ops = &gfs2_meta_aops;
772 mapping->host = s->s_bdev->bd_inode;
773 mapping->flags = 0;
774 mapping_set_gfp_mask(mapping, GFP_NOFS);
Rafael Aquini252aa6f2012-12-11 16:02:35 -0800775 mapping->private_data = NULL;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000776 mapping->backing_dev_info = s->s_bdi;
777 mapping->writeback_index = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000778 }
779
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000780 spin_lock_bucket(hash);
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400781 tmp = search_bucket(hash, sdp, &name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000782 if (tmp) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000783 spin_unlock_bucket(hash);
David Teigland4e2f8842012-11-14 13:47:37 -0500784 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000785 kmem_cache_free(cachep, gl);
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000786 atomic_dec(&sdp->sd_glock_disposal);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000787 gl = tmp;
788 } else {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000789 hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]);
790 spin_unlock_bucket(hash);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000791 }
792
793 *glp = gl;
794
795 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000796}
797
798/**
799 * gfs2_holder_init - initialize a struct gfs2_holder in the default way
800 * @gl: the glock
801 * @state: the state we're requesting
802 * @flags: the modifier flags
803 * @gh: the holder structure
804 *
805 */
806
Steven Whitehouse190562b2006-04-20 16:57:23 -0400807void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000808 struct gfs2_holder *gh)
809{
810 INIT_LIST_HEAD(&gh->gh_list);
811 gh->gh_gl = gl;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500812 gh->gh_ip = (unsigned long)__builtin_return_address(0);
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800813 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000814 gh->gh_state = state;
815 gh->gh_flags = flags;
816 gh->gh_error = 0;
817 gh->gh_iflags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000818 gfs2_glock_hold(gl);
819}
820
821/**
822 * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it
823 * @state: the state we're requesting
824 * @flags: the modifier flags
825 * @gh: the holder structure
826 *
827 * Don't mess with the glock.
828 *
829 */
830
Steven Whitehouse190562b2006-04-20 16:57:23 -0400831void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000832{
833 gh->gh_state = state;
Steven Whitehouse579b78a2006-04-26 14:58:26 -0400834 gh->gh_flags = flags;
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000835 gh->gh_iflags = 0;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500836 gh->gh_ip = (unsigned long)__builtin_return_address(0);
Bob Peterson1a0eae82010-04-14 11:58:16 -0400837 if (gh->gh_owner_pid)
838 put_pid(gh->gh_owner_pid);
839 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000840}
841
842/**
843 * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
844 * @gh: the holder structure
845 *
846 */
847
848void gfs2_holder_uninit(struct gfs2_holder *gh)
849{
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800850 put_pid(gh->gh_owner_pid);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000851 gfs2_glock_put(gh->gh_gl);
852 gh->gh_gl = NULL;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500853 gh->gh_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000854}
855
Steven Whitehousefe64d512009-05-19 10:01:18 +0100856/**
857 * gfs2_glock_holder_wait
858 * @word: unused
859 *
860 * This function and gfs2_glock_demote_wait both show up in the WCHAN
861 * field. Thus I've separated these otherwise identical functions in
862 * order to be more informative to the user.
863 */
864
865static int gfs2_glock_holder_wait(void *word)
Steven Whitehousefee852e2007-01-17 15:33:23 +0000866{
867 schedule();
868 return 0;
869}
870
Steven Whitehousefe64d512009-05-19 10:01:18 +0100871static int gfs2_glock_demote_wait(void *word)
872{
873 schedule();
874 return 0;
875}
876
Bob Peterson07a79042012-08-09 12:48:44 -0500877/**
878 * gfs2_glock_wait - wait on a glock acquisition
879 * @gh: the glock holder
880 *
881 * Returns: 0 on success
882 */
883
884int gfs2_glock_wait(struct gfs2_holder *gh)
Steven Whitehousefee852e2007-01-17 15:33:23 +0000885{
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400886 unsigned long time1 = jiffies;
887
Steven Whitehousefee852e2007-01-17 15:33:23 +0000888 might_sleep();
Steven Whitehousefe64d512009-05-19 10:01:18 +0100889 wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400890 if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */
891 /* Lengthen the minimum hold time. */
892 gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time +
893 GL_GLOCK_HOLD_INCR,
894 GL_GLOCK_MAX_HOLD);
Bob Peterson07a79042012-08-09 12:48:44 -0500895 return gh->gh_error;
Abhijith Dasd93cfa92007-06-11 08:22:32 +0100896}
897
David Teiglandb3b94fa2006-01-16 16:50:04 +0000898/**
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000899 * handle_callback - process a demote request
David Teiglandb3b94fa2006-01-16 16:50:04 +0000900 * @gl: the glock
901 * @state: the state the caller wants us to change to
902 *
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000903 * There are only two requests that we are going to see in actual
904 * practise: LM_ST_SHARED and LM_ST_UNLOCKED
David Teiglandb3b94fa2006-01-16 16:50:04 +0000905 */
906
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500907static void handle_callback(struct gfs2_glock *gl, unsigned int state,
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100908 unsigned long delay, bool remote)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000909{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500910 int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE;
911
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500912 set_bit(bit, &gl->gl_flags);
913 if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000914 gl->gl_demote_state = state;
915 gl->gl_demote_time = jiffies;
Josef Whiter26caee52007-07-23 10:02:40 +0100916 } else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
917 gl->gl_demote_state != state) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100918 gl->gl_demote_state = LM_ST_UNLOCKED;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000919 }
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500920 if (gl->gl_ops->go_callback)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100921 gl->gl_ops->go_callback(gl, remote);
Steven Whitehouse7bd8b2e2013-04-10 10:32:05 +0100922 trace_gfs2_demote_rq(gl, remote);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000923}
924
Steven Whitehouse6802e342008-05-21 17:03:22 +0100925void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
Robert Peterson7c52b162007-03-16 10:26:37 +0000926{
Joe Perches5e690692010-11-09 16:35:20 -0800927 struct va_format vaf;
Robert Peterson7c52b162007-03-16 10:26:37 +0000928 va_list args;
929
930 va_start(args, fmt);
Joe Perches5e690692010-11-09 16:35:20 -0800931
Steven Whitehouse6802e342008-05-21 17:03:22 +0100932 if (seq) {
Steven Whitehouse1bb49302012-06-11 13:26:50 +0100933 seq_vprintf(seq, fmt, args);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100934 } else {
Joe Perches5e690692010-11-09 16:35:20 -0800935 vaf.fmt = fmt;
936 vaf.va = &args;
937
938 printk(KERN_ERR " %pV", &vaf);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100939 }
Joe Perches5e690692010-11-09 16:35:20 -0800940
Robert Peterson7c52b162007-03-16 10:26:37 +0000941 va_end(args);
942}
943
David Teiglandb3b94fa2006-01-16 16:50:04 +0000944/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000945 * add_to_queue - Add a holder to the wait queue (but look for recursion)
946 * @gh: the holder structure to add
947 *
Steven Whitehouse6802e342008-05-21 17:03:22 +0100948 * Eventually we should move the recursive locking trap to a
949 * debugging option or something like that. This is the fast
950 * path and needs to have the minimum number of distractions.
951 *
David Teiglandb3b94fa2006-01-16 16:50:04 +0000952 */
953
Steven Whitehouse6802e342008-05-21 17:03:22 +0100954static inline void add_to_queue(struct gfs2_holder *gh)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700955__releases(&gl->gl_spin)
956__acquires(&gl->gl_spin)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000957{
958 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100959 struct gfs2_sbd *sdp = gl->gl_sbd;
960 struct list_head *insert_pt = NULL;
961 struct gfs2_holder *gh2;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500962 int try_futile = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000963
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800964 BUG_ON(gh->gh_owner_pid == NULL);
Steven Whitehousefee852e2007-01-17 15:33:23 +0000965 if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
966 BUG();
Steven Whitehouse190562b2006-04-20 16:57:23 -0400967
Steven Whitehouse6802e342008-05-21 17:03:22 +0100968 if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
969 if (test_bit(GLF_LOCK, &gl->gl_flags))
Bob Petersone5dc76b2012-08-09 12:48:46 -0500970 try_futile = !may_grant(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100971 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
972 goto fail;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000973 }
974
Steven Whitehouse6802e342008-05-21 17:03:22 +0100975 list_for_each_entry(gh2, &gl->gl_holders, gh_list) {
976 if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
977 (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK)))
978 goto trap_recursive;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500979 if (try_futile &&
980 !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100981fail:
982 gh->gh_error = GLR_TRYFAILED;
983 gfs2_holder_wake(gh);
984 return;
985 }
986 if (test_bit(HIF_HOLDER, &gh2->gh_iflags))
987 continue;
988 if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt))
989 insert_pt = &gh2->gh_list;
990 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100991 set_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouseedae38a2011-01-31 09:38:12 +0000992 trace_gfs2_glock_queue(gh, 1);
Steven Whitehousea2457692012-01-20 10:38:36 +0000993 gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
994 gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100995 if (likely(insert_pt == NULL)) {
996 list_add_tail(&gh->gh_list, &gl->gl_holders);
997 if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
998 goto do_cancel;
999 return;
1000 }
1001 list_add_tail(&gh->gh_list, insert_pt);
1002do_cancel:
1003 gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
1004 if (!(gh->gh_flags & LM_FLAG_PRIORITY)) {
1005 spin_unlock(&gl->gl_spin);
Steven Whitehouse048bca22008-05-23 14:46:04 +01001006 if (sdp->sd_lockstruct.ls_ops->lm_cancel)
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001007 sdp->sd_lockstruct.ls_ops->lm_cancel(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001008 spin_lock(&gl->gl_spin);
1009 }
1010 return;
1011
1012trap_recursive:
Joe Perches7af584d2012-12-12 10:19:08 -08001013 printk(KERN_ERR "original: %pSR\n", (void *)gh2->gh_ip);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001014 printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid));
1015 printk(KERN_ERR "lock type: %d req lock state : %d\n",
1016 gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
Joe Perches7af584d2012-12-12 10:19:08 -08001017 printk(KERN_ERR "new: %pSR\n", (void *)gh->gh_ip);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001018 printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid));
1019 printk(KERN_ERR "lock type: %d req lock state : %d\n",
1020 gh->gh_gl->gl_name.ln_type, gh->gh_state);
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001021 gfs2_dump_glock(NULL, gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001022 BUG();
David Teiglandb3b94fa2006-01-16 16:50:04 +00001023}
1024
1025/**
1026 * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock)
1027 * @gh: the holder structure
1028 *
1029 * if (gh->gh_flags & GL_ASYNC), this never returns an error
1030 *
1031 * Returns: 0, GLR_TRYFAILED, or errno on failure
1032 */
1033
1034int gfs2_glock_nq(struct gfs2_holder *gh)
1035{
1036 struct gfs2_glock *gl = gh->gh_gl;
1037 struct gfs2_sbd *sdp = gl->gl_sbd;
1038 int error = 0;
1039
Steven Whitehouse6802e342008-05-21 17:03:22 +01001040 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001041 return -EIO;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001042
Steven Whitehousef42ab082011-04-14 16:50:31 +01001043 if (test_bit(GLF_LRU, &gl->gl_flags))
1044 gfs2_glock_remove_from_lru(gl);
1045
David Teiglandb3b94fa2006-01-16 16:50:04 +00001046 spin_lock(&gl->gl_spin);
1047 add_to_queue(gh);
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001048 if ((LM_FLAG_NOEXP & gh->gh_flags) &&
1049 test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
1050 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001051 run_queue(gl, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001052 spin_unlock(&gl->gl_spin);
1053
Steven Whitehouse6802e342008-05-21 17:03:22 +01001054 if (!(gh->gh_flags & GL_ASYNC))
1055 error = gfs2_glock_wait(gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001056
David Teiglandb3b94fa2006-01-16 16:50:04 +00001057 return error;
1058}
1059
1060/**
1061 * gfs2_glock_poll - poll to see if an async request has been completed
1062 * @gh: the holder
1063 *
1064 * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on
1065 */
1066
1067int gfs2_glock_poll(struct gfs2_holder *gh)
1068{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001069 return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001070}
1071
1072/**
1073 * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock)
1074 * @gh: the glock holder
1075 *
1076 */
1077
1078void gfs2_glock_dq(struct gfs2_holder *gh)
1079{
1080 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001081 const struct gfs2_glock_operations *glops = gl->gl_ops;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001082 unsigned delay = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001083 int fast_path = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001084
Steven Whitehouse6802e342008-05-21 17:03:22 +01001085 spin_lock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001086 if (gh->gh_flags & GL_NOCACHE)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001087 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001088
David Teiglandb3b94fa2006-01-16 16:50:04 +00001089 list_del_init(&gh->gh_list);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001090 if (find_first_holder(gl) == NULL) {
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001091 if (glops->go_unlock) {
Steven Whitehouse6802e342008-05-21 17:03:22 +01001092 GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags));
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001093 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001094 glops->go_unlock(gh);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001095 spin_lock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001096 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001097 }
Steven Whitehouse6802e342008-05-21 17:03:22 +01001098 if (list_empty(&gl->gl_holders) &&
1099 !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
1100 !test_bit(GLF_DEMOTE, &gl->gl_flags))
1101 fast_path = 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001102 }
Bob Peterson4abb6ad2012-08-09 12:48:43 -05001103 if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl))
1104 gfs2_glock_add_to_lru(gl);
1105
Steven Whitehouse63997772009-06-12 08:49:20 +01001106 trace_gfs2_glock_queue(gh, 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001107 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001108 if (likely(fast_path))
1109 return;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001110
1111 gfs2_glock_hold(gl);
1112 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001113 !test_bit(GLF_DEMOTE, &gl->gl_flags) &&
1114 gl->gl_name.ln_type == LM_TYPE_INODE)
1115 delay = gl->gl_hold_time;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001116 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1117 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001118}
1119
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001120void gfs2_glock_dq_wait(struct gfs2_holder *gh)
1121{
1122 struct gfs2_glock *gl = gh->gh_gl;
1123 gfs2_glock_dq(gh);
Bob Peterson81e1d452012-08-09 12:48:45 -05001124 might_sleep();
1125 wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE);
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001126}
1127
David Teiglandb3b94fa2006-01-16 16:50:04 +00001128/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001129 * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
1130 * @gh: the holder structure
1131 *
1132 */
1133
1134void gfs2_glock_dq_uninit(struct gfs2_holder *gh)
1135{
1136 gfs2_glock_dq(gh);
1137 gfs2_holder_uninit(gh);
1138}
1139
1140/**
1141 * gfs2_glock_nq_num - acquire a glock based on lock number
1142 * @sdp: the filesystem
1143 * @number: the lock number
1144 * @glops: the glock operations for the type of glock
1145 * @state: the state to acquire the glock in
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001146 * @flags: modifier flags for the acquisition
David Teiglandb3b94fa2006-01-16 16:50:04 +00001147 * @gh: the struct gfs2_holder
1148 *
1149 * Returns: errno
1150 */
1151
Steven Whitehousecd915492006-09-04 12:49:07 -04001152int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001153 const struct gfs2_glock_operations *glops,
1154 unsigned int state, int flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001155{
1156 struct gfs2_glock *gl;
1157 int error;
1158
1159 error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
1160 if (!error) {
1161 error = gfs2_glock_nq_init(gl, state, flags, gh);
1162 gfs2_glock_put(gl);
1163 }
1164
1165 return error;
1166}
1167
1168/**
1169 * glock_compare - Compare two struct gfs2_glock structures for sorting
1170 * @arg_a: the first structure
1171 * @arg_b: the second structure
1172 *
1173 */
1174
1175static int glock_compare(const void *arg_a, const void *arg_b)
1176{
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001177 const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a;
1178 const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b;
1179 const struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1180 const struct lm_lockname *b = &gh_b->gh_gl->gl_name;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001181
1182 if (a->ln_number > b->ln_number)
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001183 return 1;
1184 if (a->ln_number < b->ln_number)
1185 return -1;
Steven Whitehouse1c0f4872007-01-22 12:10:39 -05001186 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 -04001187 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001188}
1189
1190/**
1191 * nq_m_sync - synchonously acquire more than one glock in deadlock free order
1192 * @num_gh: the number of structures
1193 * @ghs: an array of struct gfs2_holder structures
1194 *
1195 * Returns: 0 on success (all glocks acquired),
1196 * errno on failure (no glocks acquired)
1197 */
1198
1199static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs,
1200 struct gfs2_holder **p)
1201{
1202 unsigned int x;
1203 int error = 0;
1204
1205 for (x = 0; x < num_gh; x++)
1206 p[x] = &ghs[x];
1207
1208 sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL);
1209
1210 for (x = 0; x < num_gh; x++) {
1211 p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1212
1213 error = gfs2_glock_nq(p[x]);
1214 if (error) {
1215 while (x--)
1216 gfs2_glock_dq(p[x]);
1217 break;
1218 }
1219 }
1220
1221 return error;
1222}
1223
1224/**
1225 * gfs2_glock_nq_m - acquire multiple glocks
1226 * @num_gh: the number of structures
1227 * @ghs: an array of struct gfs2_holder structures
1228 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001229 *
1230 * Returns: 0 on success (all glocks acquired),
1231 * errno on failure (no glocks acquired)
1232 */
1233
1234int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1235{
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001236 struct gfs2_holder *tmp[4];
1237 struct gfs2_holder **pph = tmp;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001238 int error = 0;
1239
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001240 switch(num_gh) {
1241 case 0:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001242 return 0;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001243 case 1:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001244 ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1245 return gfs2_glock_nq(ghs);
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001246 default:
1247 if (num_gh <= 4)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001248 break;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001249 pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS);
1250 if (!pph)
1251 return -ENOMEM;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001252 }
1253
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001254 error = nq_m_sync(num_gh, ghs, pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001255
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001256 if (pph != tmp)
1257 kfree(pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001258
1259 return error;
1260}
1261
1262/**
1263 * gfs2_glock_dq_m - release multiple glocks
1264 * @num_gh: the number of structures
1265 * @ghs: an array of struct gfs2_holder structures
1266 *
1267 */
1268
1269void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1270{
Bob Petersonfa1bbde2011-03-10 11:41:57 -05001271 while (num_gh--)
1272 gfs2_glock_dq(&ghs[num_gh]);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001273}
1274
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001275void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
Steven Whitehouseda755fd2008-01-30 15:34:04 +00001276{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001277 unsigned long delay = 0;
1278 unsigned long holdtime;
1279 unsigned long now = jiffies;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001280
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001281 gfs2_glock_hold(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001282 holdtime = gl->gl_tchange + gl->gl_hold_time;
1283 if (test_bit(GLF_QUEUED, &gl->gl_flags) &&
1284 gl->gl_name.ln_type == LM_TYPE_INODE) {
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001285 if (time_before(now, holdtime))
1286 delay = holdtime - now;
1287 if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001288 delay = gl->gl_hold_time;
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001289 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001290
Steven Whitehouse6802e342008-05-21 17:03:22 +01001291 spin_lock(&gl->gl_spin);
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001292 handle_callback(gl, state, delay, true);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001293 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001294 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1295 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001296}
1297
1298/**
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001299 * gfs2_should_freeze - Figure out if glock should be frozen
1300 * @gl: The glock in question
1301 *
1302 * Glocks are not frozen if (a) the result of the dlm operation is
1303 * an error, (b) the locking operation was an unlock operation or
1304 * (c) if there is a "noexp" flagged request anywhere in the queue
1305 *
1306 * Returns: 1 if freezing should occur, 0 otherwise
1307 */
1308
1309static int gfs2_should_freeze(const struct gfs2_glock *gl)
1310{
1311 const struct gfs2_holder *gh;
1312
1313 if (gl->gl_reply & ~LM_OUT_ST_MASK)
1314 return 0;
1315 if (gl->gl_target == LM_ST_UNLOCKED)
1316 return 0;
1317
1318 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
1319 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
1320 continue;
1321 if (LM_FLAG_NOEXP & gh->gh_flags)
1322 return 0;
1323 }
1324
1325 return 1;
1326}
1327
1328/**
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001329 * gfs2_glock_complete - Callback used by locking
1330 * @gl: Pointer to the glock
1331 * @ret: The return value from the dlm
David Teiglandb3b94fa2006-01-16 16:50:04 +00001332 *
Steven Whitehouse47a25382010-11-30 15:49:31 +00001333 * The gl_reply field is under the gl_spin lock so that it is ok
1334 * to use a bitfield shared with other glock state fields.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001335 */
1336
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001337void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001338{
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001339 struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001340
Steven Whitehouse47a25382010-11-30 15:49:31 +00001341 spin_lock(&gl->gl_spin);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001342 gl->gl_reply = ret;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001343
David Teiglande0c2a9a2012-01-09 17:18:05 -05001344 if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001345 if (gfs2_should_freeze(gl)) {
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001346 set_bit(GLF_FROZEN, &gl->gl_flags);
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001347 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001348 return;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001349 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001350 }
Steven Whitehouse47a25382010-11-30 15:49:31 +00001351
Steven Whitehousee66cf162013-10-15 15:18:08 +01001352 gl->gl_lockref.count++;
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001353 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001354 spin_unlock(&gl->gl_spin);
1355
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001356 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1357 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001358}
1359
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001360static int glock_cmp(void *priv, struct list_head *a, struct list_head *b)
1361{
1362 struct gfs2_glock *gla, *glb;
1363
1364 gla = list_entry(a, struct gfs2_glock, gl_lru);
1365 glb = list_entry(b, struct gfs2_glock, gl_lru);
1366
1367 if (gla->gl_name.ln_number > glb->gl_name.ln_number)
1368 return 1;
1369 if (gla->gl_name.ln_number < glb->gl_name.ln_number)
1370 return -1;
1371
1372 return 0;
1373}
1374
1375/**
1376 * gfs2_dispose_glock_lru - Demote a list of glocks
1377 * @list: The list to dispose of
1378 *
1379 * Disposing of glocks may involve disk accesses, so that here we sort
1380 * the glocks by number (i.e. disk location of the inodes) so that if
1381 * there are any such accesses, they'll be sent in order (mostly).
1382 *
1383 * Must be called under the lru_lock, but may drop and retake this
1384 * lock. While the lru_lock is dropped, entries may vanish from the
1385 * list, but no new entries will appear on the list (since it is
1386 * private)
1387 */
1388
1389static void gfs2_dispose_glock_lru(struct list_head *list)
1390__releases(&lru_lock)
1391__acquires(&lru_lock)
1392{
1393 struct gfs2_glock *gl;
1394
1395 list_sort(NULL, list, glock_cmp);
1396
1397 while(!list_empty(list)) {
1398 gl = list_entry(list->next, struct gfs2_glock, gl_lru);
1399 list_del_init(&gl->gl_lru);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001400 if (!spin_trylock(&gl->gl_spin)) {
1401 list_add(&gl->gl_lru, &lru_list);
1402 atomic_inc(&lru_count);
1403 continue;
1404 }
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001405 clear_bit(GLF_LRU, &gl->gl_flags);
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001406 spin_unlock(&lru_lock);
Steven Whitehousee66cf162013-10-15 15:18:08 +01001407 gl->gl_lockref.count++;
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001408 if (demote_ok(gl))
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001409 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001410 WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001411 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
Steven Whitehousee66cf162013-10-15 15:18:08 +01001412 gl->gl_lockref.count--;
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001413 spin_unlock(&gl->gl_spin);
1414 spin_lock(&lru_lock);
1415 }
1416}
1417
Steven Whitehouse2a005852012-12-14 12:28:30 +00001418/**
1419 * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote
1420 * @nr: The number of entries to scan
1421 *
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001422 * This function selects the entries on the LRU which are able to
1423 * be demoted, and then kicks off the process by calling
1424 * gfs2_dispose_glock_lru() above.
Steven Whitehouse2a005852012-12-14 12:28:30 +00001425 */
David Teiglandb3b94fa2006-01-16 16:50:04 +00001426
Dave Chinner1ab6c492013-08-28 10:18:09 +10001427static long gfs2_scan_glock_lru(int nr)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001428{
1429 struct gfs2_glock *gl;
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001430 LIST_HEAD(skipped);
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001431 LIST_HEAD(dispose);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001432 long freed = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001433
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001434 spin_lock(&lru_lock);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001435 while ((nr-- >= 0) && !list_empty(&lru_list)) {
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001436 gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001437
1438 /* Test for being demotable */
1439 if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001440 list_move(&gl->gl_lru, &dispose);
1441 atomic_dec(&lru_count);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001442 freed++;
Steven Whitehouse2163b1e2009-06-25 16:30:26 +01001443 continue;
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001444 }
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001445
1446 list_move(&gl->gl_lru, &skipped);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001447 }
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001448 list_splice(&skipped, &lru_list);
Steven Whitehouse4506a5192013-02-01 20:36:03 +00001449 if (!list_empty(&dispose))
1450 gfs2_dispose_glock_lru(&dispose);
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001451 spin_unlock(&lru_lock);
Dave Chinner1ab6c492013-08-28 10:18:09 +10001452
1453 return freed;
Steven Whitehouse2a005852012-12-14 12:28:30 +00001454}
1455
Dave Chinner1ab6c492013-08-28 10:18:09 +10001456static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
1457 struct shrink_control *sc)
Steven Whitehouse2a005852012-12-14 12:28:30 +00001458{
Dave Chinner1ab6c492013-08-28 10:18:09 +10001459 if (!(sc->gfp_mask & __GFP_FS))
1460 return SHRINK_STOP;
1461 return gfs2_scan_glock_lru(sc->nr_to_scan);
1462}
Steven Whitehouse2a005852012-12-14 12:28:30 +00001463
Dave Chinner1ab6c492013-08-28 10:18:09 +10001464static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
1465 struct shrink_control *sc)
1466{
Glauber Costa55f841c2013-08-28 10:17:53 +10001467 return vfs_pressure_ratio(atomic_read(&lru_count));
David Teiglandb3b94fa2006-01-16 16:50:04 +00001468}
1469
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001470static struct shrinker glock_shrinker = {
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001471 .seeks = DEFAULT_SEEKS,
Dave Chinner1ab6c492013-08-28 10:18:09 +10001472 .count_objects = gfs2_glock_shrink_count,
1473 .scan_objects = gfs2_glock_shrink_scan,
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001474};
1475
David Teiglandb3b94fa2006-01-16 16:50:04 +00001476/**
1477 * examine_bucket - Call a function for glock in a hash bucket
1478 * @examiner: the function
1479 * @sdp: the filesystem
1480 * @bucket: the bucket
1481 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001482 */
1483
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001484static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp,
Steven Whitehouse37b2fa62006-09-08 13:35:56 -04001485 unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001486{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001487 struct gfs2_glock *gl;
1488 struct hlist_bl_head *head = &gl_hash_table[hash];
1489 struct hlist_bl_node *pos;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001490
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001491 rcu_read_lock();
1492 hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) {
Steven Whitehousee66cf162013-10-15 15:18:08 +01001493 if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref))
Steven Whitehouse24264432006-09-11 21:40:30 -04001494 examiner(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001495 }
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001496 rcu_read_unlock();
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001497 cond_resched();
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001498}
1499
1500static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
1501{
1502 unsigned x;
1503
1504 for (x = 0; x < GFS2_GL_HASH_SIZE; x++)
1505 examine_bucket(examiner, sdp, x);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001506}
1507
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001508
1509/**
1510 * thaw_glock - thaw out a glock which has an unprocessed reply waiting
1511 * @gl: The glock to thaw
1512 *
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001513 */
1514
1515static void thaw_glock(struct gfs2_glock *gl)
1516{
1517 if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
Steven Whitehouse7286b312013-08-20 09:35:09 +01001518 goto out;
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001519 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehouse7286b312013-08-20 09:35:09 +01001520 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) {
1521out:
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001522 gfs2_glock_put(gl);
Steven Whitehouse7286b312013-08-20 09:35:09 +01001523 }
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001524}
1525
David Teiglandb3b94fa2006-01-16 16:50:04 +00001526/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001527 * clear_glock - look at a glock and see if we can free it from glock cache
1528 * @gl: the glock to look at
1529 *
1530 */
1531
1532static void clear_glock(struct gfs2_glock *gl)
1533{
Steven Whitehousef42ab082011-04-14 16:50:31 +01001534 gfs2_glock_remove_from_lru(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001535
Steven Whitehouse6802e342008-05-21 17:03:22 +01001536 spin_lock(&gl->gl_spin);
Steven Whitehousec741c452010-09-29 14:20:52 +01001537 if (gl->gl_state != LM_ST_UNLOCKED)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001538 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001539 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001540 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1541 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001542}
1543
1544/**
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001545 * gfs2_glock_thaw - Thaw any frozen glocks
1546 * @sdp: The super block
1547 *
1548 */
1549
1550void gfs2_glock_thaw(struct gfs2_sbd *sdp)
1551{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001552 glock_hash_walk(thaw_glock, sdp);
1553}
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001554
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001555static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
1556{
1557 int ret;
1558 spin_lock(&gl->gl_spin);
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001559 ret = gfs2_dump_glock(seq, gl);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001560 spin_unlock(&gl->gl_spin);
1561 return ret;
1562}
1563
1564static void dump_glock_func(struct gfs2_glock *gl)
1565{
1566 dump_glock(NULL, gl);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001567}
1568
1569/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001570 * gfs2_gl_hash_clear - Empty out the glock hash table
1571 * @sdp: the filesystem
1572 * @wait: wait until it's all gone
1573 *
Steven Whitehouse1bdad602008-06-03 14:09:53 +01001574 * Called when unmounting the filesystem.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001575 */
1576
Steven Whitehousefefc03b2008-12-19 15:32:06 +00001577void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001578{
David Teiglandfb6791d2012-11-13 10:58:56 -05001579 set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
Bob Peterson222cb532013-04-25 12:49:17 -04001580 flush_workqueue(glock_workqueue);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001581 glock_hash_walk(clear_glock, sdp);
Steven Whitehouse8f052282010-01-29 15:21:27 +00001582 flush_workqueue(glock_workqueue);
1583 wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0);
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001584 glock_hash_walk(dump_glock_func, sdp);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001585}
1586
Steven Whitehouse813e0c42008-11-18 13:38:48 +00001587void gfs2_glock_finish_truncate(struct gfs2_inode *ip)
1588{
1589 struct gfs2_glock *gl = ip->i_gl;
1590 int ret;
1591
1592 ret = gfs2_truncatei_resume(ip);
1593 gfs2_assert_withdraw(gl->gl_sbd, ret == 0);
1594
1595 spin_lock(&gl->gl_spin);
1596 clear_bit(GLF_LOCK, &gl->gl_flags);
1597 run_queue(gl, 1);
1598 spin_unlock(&gl->gl_spin);
1599}
1600
Steven Whitehouse6802e342008-05-21 17:03:22 +01001601static const char *state2str(unsigned state)
Robert Peterson04b933f2007-03-23 17:05:15 -05001602{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001603 switch(state) {
1604 case LM_ST_UNLOCKED:
1605 return "UN";
1606 case LM_ST_SHARED:
1607 return "SH";
1608 case LM_ST_DEFERRED:
1609 return "DF";
1610 case LM_ST_EXCLUSIVE:
1611 return "EX";
1612 }
1613 return "??";
1614}
Robert Peterson04b933f2007-03-23 17:05:15 -05001615
Steven Whitehouse6802e342008-05-21 17:03:22 +01001616static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags)
1617{
1618 char *p = buf;
1619 if (flags & LM_FLAG_TRY)
1620 *p++ = 't';
1621 if (flags & LM_FLAG_TRY_1CB)
1622 *p++ = 'T';
1623 if (flags & LM_FLAG_NOEXP)
1624 *p++ = 'e';
1625 if (flags & LM_FLAG_ANY)
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001626 *p++ = 'A';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001627 if (flags & LM_FLAG_PRIORITY)
1628 *p++ = 'p';
1629 if (flags & GL_ASYNC)
1630 *p++ = 'a';
1631 if (flags & GL_EXACT)
1632 *p++ = 'E';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001633 if (flags & GL_NOCACHE)
1634 *p++ = 'c';
1635 if (test_bit(HIF_HOLDER, &iflags))
1636 *p++ = 'H';
1637 if (test_bit(HIF_WAIT, &iflags))
1638 *p++ = 'W';
1639 if (test_bit(HIF_FIRST, &iflags))
1640 *p++ = 'F';
1641 *p = 0;
1642 return buf;
Robert Peterson04b933f2007-03-23 17:05:15 -05001643}
1644
David Teiglandb3b94fa2006-01-16 16:50:04 +00001645/**
1646 * dump_holder - print information about a glock holder
Steven Whitehouse6802e342008-05-21 17:03:22 +01001647 * @seq: the seq_file struct
David Teiglandb3b94fa2006-01-16 16:50:04 +00001648 * @gh: the glock holder
1649 *
1650 * Returns: 0 on success, -ENOBUFS when we run out of space
1651 */
1652
Steven Whitehouse6802e342008-05-21 17:03:22 +01001653static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001654{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001655 struct task_struct *gh_owner = NULL;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001656 char flags_buf[32];
David Teiglandb3b94fa2006-01-16 16:50:04 +00001657
Steven Whitehouse6802e342008-05-21 17:03:22 +01001658 if (gh->gh_owner_pid)
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -08001659 gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
Joe Perchescc181522010-11-05 16:12:36 -07001660 gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n",
1661 state2str(gh->gh_state),
1662 hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags),
1663 gh->gh_error,
1664 gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1,
1665 gh_owner ? gh_owner->comm : "(ended)",
1666 (void *)gh->gh_ip);
Robert Peterson7c52b162007-03-16 10:26:37 +00001667 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001668}
1669
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001670static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001671{
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001672 const unsigned long *gflags = &gl->gl_flags;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001673 char *p = buf;
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001674
Steven Whitehouse6802e342008-05-21 17:03:22 +01001675 if (test_bit(GLF_LOCK, gflags))
1676 *p++ = 'l';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001677 if (test_bit(GLF_DEMOTE, gflags))
1678 *p++ = 'D';
1679 if (test_bit(GLF_PENDING_DEMOTE, gflags))
1680 *p++ = 'd';
1681 if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags))
1682 *p++ = 'p';
1683 if (test_bit(GLF_DIRTY, gflags))
1684 *p++ = 'y';
1685 if (test_bit(GLF_LFLUSH, gflags))
1686 *p++ = 'f';
1687 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags))
1688 *p++ = 'i';
1689 if (test_bit(GLF_REPLY_PENDING, gflags))
1690 *p++ = 'r';
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001691 if (test_bit(GLF_INITIAL, gflags))
Steven Whitehoused8348de2009-02-05 10:12:38 +00001692 *p++ = 'I';
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001693 if (test_bit(GLF_FROZEN, gflags))
1694 *p++ = 'F';
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001695 if (test_bit(GLF_QUEUED, gflags))
1696 *p++ = 'q';
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001697 if (test_bit(GLF_LRU, gflags))
1698 *p++ = 'L';
1699 if (gl->gl_object)
1700 *p++ = 'o';
Steven Whitehousea2457692012-01-20 10:38:36 +00001701 if (test_bit(GLF_BLOCKING, gflags))
1702 *p++ = 'b';
Steven Whitehouse6802e342008-05-21 17:03:22 +01001703 *p = 0;
1704 return buf;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001705}
1706
1707/**
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001708 * gfs2_dump_glock - print information about a glock
Steven Whitehouse6802e342008-05-21 17:03:22 +01001709 * @seq: The seq_file struct
David Teiglandb3b94fa2006-01-16 16:50:04 +00001710 * @gl: the glock
Steven Whitehouse6802e342008-05-21 17:03:22 +01001711 *
1712 * The file format is as follows:
1713 * One line per object, capital letters are used to indicate objects
1714 * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented,
1715 * other objects are indented by a single space and follow the glock to
1716 * which they are related. Fields are indicated by lower case letters
1717 * followed by a colon and the field value, except for strings which are in
1718 * [] so that its possible to see if they are composed of spaces for
1719 * example. The field's are n = number (id of the object), f = flags,
1720 * t = type, s = state, r = refcount, e = error, p = pid.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001721 *
1722 * Returns: 0 on success, -ENOBUFS when we run out of space
1723 */
1724
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001725int gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001726{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001727 const struct gfs2_glock_operations *glops = gl->gl_ops;
1728 unsigned long long dtime;
1729 const struct gfs2_holder *gh;
1730 char gflags_buf[32];
1731 int error = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001732
Steven Whitehouse6802e342008-05-21 17:03:22 +01001733 dtime = jiffies - gl->gl_demote_time;
1734 dtime *= 1000000/HZ; /* demote time in uSec */
1735 if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
1736 dtime = 0;
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001737 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 +01001738 state2str(gl->gl_state),
1739 gl->gl_name.ln_type,
1740 (unsigned long long)gl->gl_name.ln_number,
Steven Whitehouse627c10b2011-04-14 14:09:52 +01001741 gflags2str(gflags_buf, gl),
Steven Whitehouse6802e342008-05-21 17:03:22 +01001742 state2str(gl->gl_target),
1743 state2str(gl->gl_demote_state), dtime,
Steven Whitehouse6802e342008-05-21 17:03:22 +01001744 atomic_read(&gl->gl_ail_count),
Steven Whitehousef42ab082011-04-14 16:50:31 +01001745 atomic_read(&gl->gl_revokes),
Steven Whitehousee66cf162013-10-15 15:18:08 +01001746 (int)gl->gl_lockref.count, gl->gl_hold_time);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001747
David Teiglandb3b94fa2006-01-16 16:50:04 +00001748 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
Steven Whitehouse6802e342008-05-21 17:03:22 +01001749 error = dump_holder(seq, gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001750 if (error)
1751 goto out;
1752 }
Steven Whitehouse6802e342008-05-21 17:03:22 +01001753 if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
1754 error = glops->go_dump(seq, gl);
Steven Whitehousea91ea692006-09-04 12:04:26 -04001755out:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001756 return error;
1757}
1758
Steven Whitehousea2457692012-01-20 10:38:36 +00001759static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
1760{
1761 struct gfs2_glock *gl = iter_ptr;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001762
Steven Whitehousea2457692012-01-20 10:38:36 +00001763 seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n",
1764 gl->gl_name.ln_type,
1765 (unsigned long long)gl->gl_name.ln_number,
1766 (long long)gl->gl_stats.stats[GFS2_LKS_SRTT],
1767 (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR],
1768 (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB],
1769 (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB],
1770 (long long)gl->gl_stats.stats[GFS2_LKS_SIRT],
1771 (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR],
1772 (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT],
1773 (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]);
1774 return 0;
1775}
David Teiglandb3b94fa2006-01-16 16:50:04 +00001776
Steven Whitehousea2457692012-01-20 10:38:36 +00001777static const char *gfs2_gltype[] = {
1778 "type",
1779 "reserved",
1780 "nondisk",
1781 "inode",
1782 "rgrp",
1783 "meta",
1784 "iopen",
1785 "flock",
1786 "plock",
1787 "quota",
1788 "journal",
1789};
1790
1791static const char *gfs2_stype[] = {
1792 [GFS2_LKS_SRTT] = "srtt",
1793 [GFS2_LKS_SRTTVAR] = "srttvar",
1794 [GFS2_LKS_SRTTB] = "srttb",
1795 [GFS2_LKS_SRTTVARB] = "srttvarb",
1796 [GFS2_LKS_SIRT] = "sirt",
1797 [GFS2_LKS_SIRTVAR] = "sirtvar",
1798 [GFS2_LKS_DCOUNT] = "dlm",
1799 [GFS2_LKS_QCOUNT] = "queue",
1800};
1801
1802#define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype))
1803
1804static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr)
1805{
1806 struct gfs2_glock_iter *gi = seq->private;
1807 struct gfs2_sbd *sdp = gi->sdp;
1808 unsigned index = gi->hash >> 3;
1809 unsigned subindex = gi->hash & 0x07;
1810 s64 value;
1811 int i;
1812
1813 if (index == 0 && subindex != 0)
1814 return 0;
1815
1816 seq_printf(seq, "%-10s %8s:", gfs2_gltype[index],
1817 (index == 0) ? "cpu": gfs2_stype[subindex]);
1818
1819 for_each_possible_cpu(i) {
1820 const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i);
1821 if (index == 0) {
1822 value = i;
1823 } else {
1824 value = lkstats->lkstats[index - 1].stats[subindex];
1825 }
1826 seq_printf(seq, " %15lld", (long long)value);
1827 }
1828 seq_putc(seq, '\n');
1829 return 0;
1830}
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001831
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001832int __init gfs2_glock_init(void)
1833{
1834 unsigned i;
1835 for(i = 0; i < GFS2_GL_HASH_SIZE; i++) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001836 INIT_HLIST_BL_HEAD(&gl_hash_table[i]);
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001837 }
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001838
Steven Whitehoused2115772010-11-03 19:58:53 +00001839 glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
Tejun Heo58a69cb2011-02-16 09:25:31 +01001840 WQ_HIGHPRI | WQ_FREEZABLE, 0);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001841 if (!glock_workqueue)
1842 return -ENOMEM;
Steven Whitehoused2115772010-11-03 19:58:53 +00001843 gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
Tejun Heo58a69cb2011-02-16 09:25:31 +01001844 WQ_MEM_RECLAIM | WQ_FREEZABLE,
Steven Whitehoused2115772010-11-03 19:58:53 +00001845 0);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001846 if (!gfs2_delete_workqueue) {
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001847 destroy_workqueue(glock_workqueue);
Dan Carpenterdfc46162013-08-15 10:54:43 +03001848 return -ENOMEM;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001849 }
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001850
1851 register_shrinker(&glock_shrinker);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001852
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001853 return 0;
1854}
1855
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001856void gfs2_glock_exit(void)
1857{
Steven Whitehouse97cc10252008-11-20 13:39:47 +00001858 unregister_shrinker(&glock_shrinker);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001859 destroy_workqueue(glock_workqueue);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001860 destroy_workqueue(gfs2_delete_workqueue);
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001861}
1862
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001863static inline struct gfs2_glock *glock_hash_chain(unsigned hash)
1864{
1865 return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]),
1866 struct gfs2_glock, gl_list);
1867}
1868
1869static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl)
1870{
Steven Whitehouse7e32d022011-03-15 08:32:14 +00001871 return hlist_bl_entry(rcu_dereference(gl->gl_list.next),
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001872 struct gfs2_glock, gl_list);
1873}
1874
Steven Whitehouse6802e342008-05-21 17:03:22 +01001875static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
Robert Peterson7c52b162007-03-16 10:26:37 +00001876{
Steven Whitehouse7b08fc62007-07-24 13:53:36 +01001877 struct gfs2_glock *gl;
1878
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001879 do {
1880 gl = gi->gl;
1881 if (gl) {
1882 gi->gl = glock_hash_next(gl);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001883 gi->nhash++;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001884 } else {
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001885 if (gi->hash >= GFS2_GL_HASH_SIZE) {
1886 rcu_read_unlock();
1887 return 1;
1888 }
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001889 gi->gl = glock_hash_chain(gi->hash);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001890 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001891 }
1892 while (gi->gl == NULL) {
1893 gi->hash++;
1894 if (gi->hash >= GFS2_GL_HASH_SIZE) {
1895 rcu_read_unlock();
1896 return 1;
1897 }
1898 gi->gl = glock_hash_chain(gi->hash);
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001899 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001900 }
1901 /* Skip entries for other sb and dead entries */
Michal Nazarewicze3c42692013-11-12 13:30:05 +01001902 } while (gi->sdp != gi->gl->gl_sbd ||
1903 __lockref_is_dead(&gi->gl->gl_lockref));
Abhijith Dasa947e032007-08-21 09:57:29 -05001904
Robert Peterson7c52b162007-03-16 10:26:37 +00001905 return 0;
1906}
1907
Steven Whitehouse6802e342008-05-21 17:03:22 +01001908static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
Robert Peterson7c52b162007-03-16 10:26:37 +00001909{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001910 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001911 loff_t n = *pos;
1912
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001913 if (gi->last_pos <= *pos)
1914 n = gi->nhash + (*pos - gi->last_pos);
1915 else
1916 gi->hash = 0;
1917
1918 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001919 rcu_read_lock();
Robert Peterson7c52b162007-03-16 10:26:37 +00001920
Steven Whitehouse6802e342008-05-21 17:03:22 +01001921 do {
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001922 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001923 return NULL;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001924 } while (n--);
Robert Peterson7c52b162007-03-16 10:26:37 +00001925
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001926 gi->last_pos = *pos;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001927 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001928}
1929
Steven Whitehouse6802e342008-05-21 17:03:22 +01001930static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
Robert Peterson7c52b162007-03-16 10:26:37 +00001931 loff_t *pos)
1932{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001933 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001934
1935 (*pos)++;
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001936 gi->last_pos = *pos;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001937 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001938 return NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001939
Steven Whitehouse6802e342008-05-21 17:03:22 +01001940 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001941}
1942
Steven Whitehouse6802e342008-05-21 17:03:22 +01001943static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001944{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001945 struct gfs2_glock_iter *gi = seq->private;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001946
1947 if (gi->gl)
1948 rcu_read_unlock();
1949 gi->gl = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001950}
1951
Steven Whitehouse6802e342008-05-21 17:03:22 +01001952static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001953{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001954 return dump_glock(seq, iter_ptr);
Robert Peterson7c52b162007-03-16 10:26:37 +00001955}
1956
Steven Whitehousea2457692012-01-20 10:38:36 +00001957static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos)
1958{
1959 struct gfs2_glock_iter *gi = seq->private;
1960
1961 gi->hash = *pos;
1962 if (*pos >= GFS2_NR_SBSTATS)
1963 return NULL;
1964 preempt_disable();
1965 return SEQ_START_TOKEN;
1966}
1967
1968static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr,
1969 loff_t *pos)
1970{
1971 struct gfs2_glock_iter *gi = seq->private;
1972 (*pos)++;
1973 gi->hash++;
1974 if (gi->hash >= GFS2_NR_SBSTATS) {
1975 preempt_enable();
1976 return NULL;
1977 }
1978 return SEQ_START_TOKEN;
1979}
1980
1981static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
1982{
1983 preempt_enable();
1984}
1985
Denis Cheng4ef29002007-07-31 18:31:11 +08001986static const struct seq_operations gfs2_glock_seq_ops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00001987 .start = gfs2_glock_seq_start,
1988 .next = gfs2_glock_seq_next,
1989 .stop = gfs2_glock_seq_stop,
1990 .show = gfs2_glock_seq_show,
1991};
1992
Steven Whitehousea2457692012-01-20 10:38:36 +00001993static const struct seq_operations gfs2_glstats_seq_ops = {
1994 .start = gfs2_glock_seq_start,
1995 .next = gfs2_glock_seq_next,
1996 .stop = gfs2_glock_seq_stop,
1997 .show = gfs2_glstats_seq_show,
1998};
1999
2000static const struct seq_operations gfs2_sbstats_seq_ops = {
2001 .start = gfs2_sbstats_seq_start,
2002 .next = gfs2_sbstats_seq_next,
2003 .stop = gfs2_sbstats_seq_stop,
2004 .show = gfs2_sbstats_seq_show,
2005};
2006
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002007#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
2008
Steven Whitehousea2457692012-01-20 10:38:36 +00002009static int gfs2_glocks_open(struct inode *inode, struct file *file)
Robert Peterson7c52b162007-03-16 10:26:37 +00002010{
Steven Whitehouse6802e342008-05-21 17:03:22 +01002011 int ret = seq_open_private(file, &gfs2_glock_seq_ops,
2012 sizeof(struct gfs2_glock_iter));
2013 if (ret == 0) {
2014 struct seq_file *seq = file->private_data;
2015 struct gfs2_glock_iter *gi = seq->private;
2016 gi->sdp = inode->i_private;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002017 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01002018 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002019 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehouse6802e342008-05-21 17:03:22 +01002020 }
2021 return ret;
Robert Peterson7c52b162007-03-16 10:26:37 +00002022}
2023
Steven Whitehousea2457692012-01-20 10:38:36 +00002024static int gfs2_glstats_open(struct inode *inode, struct file *file)
2025{
2026 int ret = seq_open_private(file, &gfs2_glstats_seq_ops,
2027 sizeof(struct gfs2_glock_iter));
2028 if (ret == 0) {
2029 struct seq_file *seq = file->private_data;
2030 struct gfs2_glock_iter *gi = seq->private;
2031 gi->sdp = inode->i_private;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002032 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01002033 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002034 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehousea2457692012-01-20 10:38:36 +00002035 }
2036 return ret;
2037}
2038
2039static int gfs2_sbstats_open(struct inode *inode, struct file *file)
2040{
2041 int ret = seq_open_private(file, &gfs2_sbstats_seq_ops,
2042 sizeof(struct gfs2_glock_iter));
2043 if (ret == 0) {
2044 struct seq_file *seq = file->private_data;
2045 struct gfs2_glock_iter *gi = seq->private;
2046 gi->sdp = inode->i_private;
2047 }
2048 return ret;
2049}
2050
2051static const struct file_operations gfs2_glocks_fops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00002052 .owner = THIS_MODULE,
Steven Whitehousea2457692012-01-20 10:38:36 +00002053 .open = gfs2_glocks_open,
2054 .read = seq_read,
2055 .llseek = seq_lseek,
2056 .release = seq_release_private,
2057};
2058
2059static const struct file_operations gfs2_glstats_fops = {
2060 .owner = THIS_MODULE,
2061 .open = gfs2_glstats_open,
2062 .read = seq_read,
2063 .llseek = seq_lseek,
2064 .release = seq_release_private,
2065};
2066
2067static const struct file_operations gfs2_sbstats_fops = {
2068 .owner = THIS_MODULE,
2069 .open = gfs2_sbstats_open,
Robert Peterson7c52b162007-03-16 10:26:37 +00002070 .read = seq_read,
2071 .llseek = seq_lseek,
Steven Whitehouse6802e342008-05-21 17:03:22 +01002072 .release = seq_release_private,
Robert Peterson7c52b162007-03-16 10:26:37 +00002073};
2074
2075int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
2076{
Robert Peterson5f882092007-04-18 11:41:11 -05002077 sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
2078 if (!sdp->debugfs_dir)
2079 return -ENOMEM;
2080 sdp->debugfs_dentry_glocks = debugfs_create_file("glocks",
2081 S_IFREG | S_IRUGO,
2082 sdp->debugfs_dir, sdp,
Steven Whitehousea2457692012-01-20 10:38:36 +00002083 &gfs2_glocks_fops);
Robert Peterson5f882092007-04-18 11:41:11 -05002084 if (!sdp->debugfs_dentry_glocks)
Steven Whitehousea2457692012-01-20 10:38:36 +00002085 goto fail;
2086
2087 sdp->debugfs_dentry_glstats = debugfs_create_file("glstats",
2088 S_IFREG | S_IRUGO,
2089 sdp->debugfs_dir, sdp,
2090 &gfs2_glstats_fops);
2091 if (!sdp->debugfs_dentry_glstats)
2092 goto fail;
2093
2094 sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats",
2095 S_IFREG | S_IRUGO,
2096 sdp->debugfs_dir, sdp,
2097 &gfs2_sbstats_fops);
2098 if (!sdp->debugfs_dentry_sbstats)
2099 goto fail;
Robert Peterson7c52b162007-03-16 10:26:37 +00002100
2101 return 0;
Steven Whitehousea2457692012-01-20 10:38:36 +00002102fail:
2103 gfs2_delete_debugfs_file(sdp);
2104 return -ENOMEM;
Robert Peterson7c52b162007-03-16 10:26:37 +00002105}
2106
2107void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
2108{
Steven Whitehousea2457692012-01-20 10:38:36 +00002109 if (sdp->debugfs_dir) {
Robert Peterson5f882092007-04-18 11:41:11 -05002110 if (sdp->debugfs_dentry_glocks) {
2111 debugfs_remove(sdp->debugfs_dentry_glocks);
2112 sdp->debugfs_dentry_glocks = NULL;
2113 }
Steven Whitehousea2457692012-01-20 10:38:36 +00002114 if (sdp->debugfs_dentry_glstats) {
2115 debugfs_remove(sdp->debugfs_dentry_glstats);
2116 sdp->debugfs_dentry_glstats = NULL;
2117 }
2118 if (sdp->debugfs_dentry_sbstats) {
2119 debugfs_remove(sdp->debugfs_dentry_sbstats);
2120 sdp->debugfs_dentry_sbstats = NULL;
2121 }
Robert Peterson5f882092007-04-18 11:41:11 -05002122 debugfs_remove(sdp->debugfs_dir);
2123 sdp->debugfs_dir = NULL;
2124 }
Robert Peterson7c52b162007-03-16 10:26:37 +00002125}
2126
2127int gfs2_register_debugfs(void)
2128{
2129 gfs2_root = debugfs_create_dir("gfs2", NULL);
2130 return gfs2_root ? 0 : -ENOMEM;
2131}
2132
2133void gfs2_unregister_debugfs(void)
2134{
2135 debugfs_remove(gfs2_root);
Robert Peterson5f882092007-04-18 11:41:11 -05002136 gfs2_root = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00002137}