blob: 9435384562a271cacd5219651269b36d5d2923c4 [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 Whitehouse4506a512013-02-01 20:36:03 +000033#include <linux/list_sort.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000034
35#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050036#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000037#include "glock.h"
38#include "glops.h"
39#include "inode.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000040#include "lops.h"
41#include "meta_io.h"
42#include "quota.h"
43#include "super.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050044#include "util.h"
Steven Whitehouse813e0c42008-11-18 13:38:48 +000045#include "bmap.h"
Steven Whitehouse63997772009-06-12 08:49:20 +010046#define CREATE_TRACE_POINTS
47#include "trace_gfs2.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000048
Steven Whitehouse6802e342008-05-21 17:03:22 +010049struct gfs2_glock_iter {
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +010050 int hash; /* hash bucket index */
51 unsigned nhash; /* Index within current bucket */
52 struct gfs2_sbd *sdp; /* incore superblock */
53 struct gfs2_glock *gl; /* current glock struct */
54 loff_t last_pos; /* last position */
Robert Peterson7c52b162007-03-16 10:26:37 +000055};
56
David Teiglandb3b94fa2006-01-16 16:50:04 +000057typedef void (*glock_examiner) (struct gfs2_glock * gl);
58
Steven Whitehouse6802e342008-05-21 17:03:22 +010059static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050060
Robert Peterson7c52b162007-03-16 10:26:37 +000061static struct dentry *gfs2_root;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -050062static struct workqueue_struct *glock_workqueue;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -050063struct workqueue_struct *gfs2_delete_workqueue;
Steven Whitehouse97cc1022008-11-20 13:39:47 +000064static LIST_HEAD(lru_list);
65static atomic_t lru_count = ATOMIC_INIT(0);
Julia Lawalleb8374e2008-12-25 15:35:27 +010066static DEFINE_SPINLOCK(lru_lock);
Adrian Bunk08bc2db2006-04-28 10:59:12 -040067
Steven Whitehouseb6397892006-09-12 10:10:01 -040068#define GFS2_GL_HASH_SHIFT 15
Steven Whitehouse087efdd2006-09-09 16:59:11 -040069#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
70#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
71
Steven Whitehousebc015cb2011-01-19 09:30:01 +000072static struct hlist_bl_head gl_hash_table[GFS2_GL_HASH_SIZE];
Robert Peterson04b933f2007-03-23 17:05:15 -050073static struct dentry *gfs2_root;
Steven Whitehouse087efdd2006-09-09 16:59:11 -040074
David Teiglandb3b94fa2006-01-16 16:50:04 +000075/**
David Teiglandb3b94fa2006-01-16 16:50:04 +000076 * gl_hash() - Turn glock number into hash bucket number
77 * @lock: The glock number
78 *
79 * Returns: The number of the corresponding hash bucket
80 */
81
Steven Whitehouseb8547852006-09-07 13:12:27 -040082static unsigned int gl_hash(const struct gfs2_sbd *sdp,
83 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +000084{
85 unsigned int h;
86
Steven Whitehousecd915492006-09-04 12:49:07 -040087 h = jhash(&name->ln_number, sizeof(u64), 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +000088 h = jhash(&name->ln_type, sizeof(unsigned int), h);
Steven Whitehouseb8547852006-09-07 13:12:27 -040089 h = jhash(&sdp, sizeof(struct gfs2_sbd *), h);
David Teiglandb3b94fa2006-01-16 16:50:04 +000090 h &= GFS2_GL_HASH_MASK;
91
92 return h;
93}
94
Steven Whitehousebc015cb2011-01-19 09:30:01 +000095static inline void spin_lock_bucket(unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +000096{
Christoph Hellwig1879fd62011-04-25 14:01:36 -040097 hlist_bl_lock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +000098}
David Teiglandb3b94fa2006-01-16 16:50:04 +000099
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000100static inline void spin_unlock_bucket(unsigned int hash)
101{
Christoph Hellwig1879fd62011-04-25 14:01:36 -0400102 hlist_bl_unlock(&gl_hash_table[hash]);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000103}
104
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000105static void gfs2_glock_dealloc(struct rcu_head *rcu)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000106{
107 struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000108
David Teiglanddba2d702012-11-14 13:46:53 -0500109 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000110 kmem_cache_free(gfs2_glock_aspace_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500111 } else {
David Teigland4e2f8842012-11-14 13:47:37 -0500112 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000113 kmem_cache_free(gfs2_glock_cachep, gl);
David Teiglanddba2d702012-11-14 13:46:53 -0500114 }
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000115}
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000116
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000117void gfs2_glock_free(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000118{
119 struct gfs2_sbd *sdp = gl->gl_sbd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000120
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000121 call_rcu(&gl->gl_rcu, gfs2_glock_dealloc);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000122 if (atomic_dec_and_test(&sdp->sd_glock_disposal))
123 wake_up(&sdp->sd_glock_wait);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000124}
125
126/**
127 * gfs2_glock_hold() - increment reference count on glock
128 * @gl: The glock to hold
129 *
130 */
131
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500132void gfs2_glock_hold(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000133{
Steven Whitehoused8348de2009-02-05 10:12:38 +0000134 GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0);
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400135 atomic_inc(&gl->gl_ref);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000136}
137
138/**
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500139 * demote_ok - Check to see if it's ok to unlock a glock
140 * @gl: the glock
141 *
142 * Returns: 1 if it's ok
143 */
144
145static int demote_ok(const struct gfs2_glock *gl)
146{
147 const struct gfs2_glock_operations *glops = gl->gl_ops;
148
149 if (gl->gl_state == LM_ST_UNLOCKED)
150 return 0;
Steven Whitehousef42ab082011-04-14 16:50:31 +0100151 if (!list_empty(&gl->gl_holders))
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500152 return 0;
153 if (glops->go_demote_ok)
154 return glops->go_demote_ok(gl);
155 return 1;
156}
157
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000158
Steven Whitehouse29687a22011-03-30 16:33:25 +0100159void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
160{
161 spin_lock(&lru_lock);
162
163 if (!list_empty(&gl->gl_lru))
164 list_del_init(&gl->gl_lru);
165 else
166 atomic_inc(&lru_count);
167
168 list_add_tail(&gl->gl_lru, &lru_list);
Steven Whitehouse627c10b2011-04-14 14:09:52 +0100169 set_bit(GLF_LRU, &gl->gl_flags);
Steven Whitehouse29687a22011-03-30 16:33:25 +0100170 spin_unlock(&lru_lock);
171}
172
Steven Whitehouse4043b882012-01-16 15:46:21 +0000173static void __gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
Steven Whitehousef42ab082011-04-14 16:50:31 +0100174{
Steven Whitehousef42ab082011-04-14 16:50:31 +0100175 if (!list_empty(&gl->gl_lru)) {
176 list_del_init(&gl->gl_lru);
177 atomic_dec(&lru_count);
178 clear_bit(GLF_LRU, &gl->gl_flags);
179 }
Steven Whitehouse4043b882012-01-16 15:46:21 +0000180}
181
182static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
183{
184 spin_lock(&lru_lock);
185 __gfs2_glock_remove_from_lru(gl);
Steven Whitehousef42ab082011-04-14 16:50:31 +0100186 spin_unlock(&lru_lock);
187}
188
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500189/**
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500190 * gfs2_glock_put_nolock() - Decrement reference count on glock
191 * @gl: The glock to put
192 *
193 * This function should only be used if the caller has its own reference
194 * to the glock, in addition to the one it is dropping.
195 */
196
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500197void gfs2_glock_put_nolock(struct gfs2_glock *gl)
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500198{
199 if (atomic_dec_and_test(&gl->gl_ref))
200 GLOCK_BUG_ON(gl, 1);
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500201}
202
203/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000204 * gfs2_glock_put() - Decrement reference count on glock
205 * @gl: The glock to put
206 *
207 */
208
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000209void gfs2_glock_put(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000210{
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000211 struct gfs2_sbd *sdp = gl->gl_sbd;
212 struct address_space *mapping = gfs2_glock2aspace(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000213
Steven Whitehouse4043b882012-01-16 15:46:21 +0000214 if (atomic_dec_and_lock(&gl->gl_ref, &lru_lock)) {
215 __gfs2_glock_remove_from_lru(gl);
216 spin_unlock(&lru_lock);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000217 spin_lock_bucket(gl->gl_hash);
218 hlist_bl_del_rcu(&gl->gl_list);
219 spin_unlock_bucket(gl->gl_hash);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100220 GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000221 GLOCK_BUG_ON(gl, mapping && mapping->nrpages);
222 trace_gfs2_glock_put(gl);
223 sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000224 }
David Teiglandb3b94fa2006-01-16 16:50:04 +0000225}
226
227/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000228 * search_bucket() - Find struct gfs2_glock by lock number
229 * @bucket: the bucket to search
230 * @name: The lock name
231 *
232 * Returns: NULL, or the struct gfs2_glock with the requested number
233 */
234
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400235static struct gfs2_glock *search_bucket(unsigned int hash,
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400236 const struct gfs2_sbd *sdp,
Steven Whitehoused6a53722006-08-30 11:16:23 -0400237 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000238{
239 struct gfs2_glock *gl;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000240 struct hlist_bl_node *h;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000241
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000242 hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000243 if (!lm_name_equal(&gl->gl_name, name))
244 continue;
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400245 if (gl->gl_sbd != sdp)
246 continue;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000247 if (atomic_inc_not_zero(&gl->gl_ref))
248 return gl;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000249 }
250
251 return NULL;
252}
253
254/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100255 * may_grant - check if its ok to grant a new lock
256 * @gl: The glock
257 * @gh: The lock request which we wish to grant
258 *
259 * Returns: true if its ok to grant the lock
260 */
261
262static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh)
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500263{
Steven Whitehouse6802e342008-05-21 17:03:22 +0100264 const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list);
265 if ((gh->gh_state == LM_ST_EXCLUSIVE ||
266 gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head)
267 return 0;
268 if (gl->gl_state == gh->gh_state)
269 return 1;
270 if (gh->gh_flags & GL_EXACT)
271 return 0;
Steven Whitehouse209806a2008-07-07 10:07:28 +0100272 if (gl->gl_state == LM_ST_EXCLUSIVE) {
273 if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED)
274 return 1;
275 if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED)
276 return 1;
277 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100278 if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY))
279 return 1;
280 return 0;
281}
282
283static void gfs2_holder_wake(struct gfs2_holder *gh)
284{
285 clear_bit(HIF_WAIT, &gh->gh_iflags);
286 smp_mb__after_clear_bit();
287 wake_up_bit(&gh->gh_iflags, HIF_WAIT);
288}
289
290/**
Steven Whitehoused5341a92010-07-23 14:05:51 +0100291 * do_error - Something unexpected has happened during a lock request
292 *
293 */
294
295static inline void do_error(struct gfs2_glock *gl, const int ret)
296{
297 struct gfs2_holder *gh, *tmp;
298
299 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
300 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
301 continue;
302 if (ret & LM_OUT_ERROR)
303 gh->gh_error = -EIO;
304 else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
305 gh->gh_error = GLR_TRYFAILED;
306 else
307 continue;
308 list_del_init(&gh->gh_list);
309 trace_gfs2_glock_queue(gh, 0);
310 gfs2_holder_wake(gh);
311 }
312}
313
314/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100315 * do_promote - promote as many requests as possible on the current queue
316 * @gl: The glock
317 *
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000318 * Returns: 1 if there is a blocked holder at the head of the list, or 2
319 * if a type specific operation is underway.
Steven Whitehouse6802e342008-05-21 17:03:22 +0100320 */
321
322static int do_promote(struct gfs2_glock *gl)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700323__releases(&gl->gl_spin)
324__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100325{
326 const struct gfs2_glock_operations *glops = gl->gl_ops;
327 struct gfs2_holder *gh, *tmp;
328 int ret;
329
330restart:
331 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
332 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
333 continue;
334 if (may_grant(gl, gh)) {
335 if (gh->gh_list.prev == &gl->gl_holders &&
336 glops->go_lock) {
337 spin_unlock(&gl->gl_spin);
338 /* FIXME: eliminate this eventually */
339 ret = glops->go_lock(gh);
340 spin_lock(&gl->gl_spin);
341 if (ret) {
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000342 if (ret == 1)
343 return 2;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100344 gh->gh_error = ret;
345 list_del_init(&gh->gh_list);
Steven Whitehouse63997772009-06-12 08:49:20 +0100346 trace_gfs2_glock_queue(gh, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100347 gfs2_holder_wake(gh);
348 goto restart;
349 }
350 set_bit(HIF_HOLDER, &gh->gh_iflags);
Steven Whitehouse63997772009-06-12 08:49:20 +0100351 trace_gfs2_promote(gh, 1);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100352 gfs2_holder_wake(gh);
353 goto restart;
354 }
355 set_bit(HIF_HOLDER, &gh->gh_iflags);
Steven Whitehouse63997772009-06-12 08:49:20 +0100356 trace_gfs2_promote(gh, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100357 gfs2_holder_wake(gh);
358 continue;
359 }
360 if (gh->gh_list.prev == &gl->gl_holders)
361 return 1;
Steven Whitehoused5341a92010-07-23 14:05:51 +0100362 do_error(gl, 0);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100363 break;
364 }
365 return 0;
366}
367
368/**
Steven Whitehouse6802e342008-05-21 17:03:22 +0100369 * find_first_waiter - find the first gh that's waiting for the glock
370 * @gl: the glock
371 */
372
373static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
374{
375 struct gfs2_holder *gh;
376
377 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
378 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
379 return gh;
380 }
381 return NULL;
382}
383
384/**
385 * state_change - record that the glock is now in a different state
386 * @gl: the glock
387 * @new_state the new state
388 *
389 */
390
391static void state_change(struct gfs2_glock *gl, unsigned int new_state)
392{
393 int held1, held2;
394
395 held1 = (gl->gl_state != LM_ST_UNLOCKED);
396 held2 = (new_state != LM_ST_UNLOCKED);
397
398 if (held1 != held2) {
399 if (held2)
400 gfs2_glock_hold(gl);
401 else
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500402 gfs2_glock_put_nolock(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100403 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100404 if (held1 && held2 && list_empty(&gl->gl_holders))
405 clear_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100406
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400407 if (new_state != gl->gl_target)
408 /* shorten our minimum hold time */
409 gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
410 GL_GLOCK_MIN_HOLD);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100411 gl->gl_state = new_state;
412 gl->gl_tchange = jiffies;
413}
414
415static void gfs2_demote_wake(struct gfs2_glock *gl)
416{
417 gl->gl_demote_state = LM_ST_EXCLUSIVE;
418 clear_bit(GLF_DEMOTE, &gl->gl_flags);
419 smp_mb__after_clear_bit();
420 wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
421}
422
423/**
424 * finish_xmote - The DLM has replied to one of our lock requests
425 * @gl: The glock
426 * @ret: The status from the DLM
427 *
428 */
429
430static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
431{
432 const struct gfs2_glock_operations *glops = gl->gl_ops;
433 struct gfs2_holder *gh;
434 unsigned state = ret & LM_OUT_ST_MASK;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000435 int rv;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500436
437 spin_lock(&gl->gl_spin);
Steven Whitehouse63997772009-06-12 08:49:20 +0100438 trace_gfs2_glock_state_change(gl, state);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100439 state_change(gl, state);
440 gh = find_first_waiter(gl);
441
442 /* Demote to UN request arrived during demote to SH or DF */
443 if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
444 state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
445 gl->gl_target = LM_ST_UNLOCKED;
446
447 /* Check for state != intended state */
448 if (unlikely(state != gl->gl_target)) {
449 if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
450 /* move to back of queue and try next entry */
451 if (ret & LM_OUT_CANCELED) {
452 if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
453 list_move_tail(&gh->gh_list, &gl->gl_holders);
454 gh = find_first_waiter(gl);
455 gl->gl_target = gh->gh_state;
456 goto retry;
457 }
458 /* Some error or failed "try lock" - report it */
459 if ((ret & LM_OUT_ERROR) ||
460 (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
461 gl->gl_target = gl->gl_state;
462 do_error(gl, ret);
463 goto out;
464 }
465 }
466 switch(state) {
467 /* Unlocked due to conversion deadlock, try again */
468 case LM_ST_UNLOCKED:
469retry:
470 do_xmote(gl, gh, gl->gl_target);
471 break;
472 /* Conversion fails, unlock and try again */
473 case LM_ST_SHARED:
474 case LM_ST_DEFERRED:
475 do_xmote(gl, gh, LM_ST_UNLOCKED);
476 break;
477 default: /* Everything else */
478 printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state);
479 GLOCK_BUG_ON(gl, 1);
480 }
481 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100482 return;
483 }
484
485 /* Fast path - we got what we asked for */
486 if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
487 gfs2_demote_wake(gl);
488 if (state != LM_ST_UNLOCKED) {
489 if (glops->go_xmote_bh) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100490 spin_unlock(&gl->gl_spin);
491 rv = glops->go_xmote_bh(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100492 spin_lock(&gl->gl_spin);
493 if (rv) {
494 do_error(gl, rv);
495 goto out;
496 }
497 }
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000498 rv = do_promote(gl);
499 if (rv == 2)
500 goto out_locked;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100501 }
502out:
503 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000504out_locked:
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500505 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500506}
507
Steven Whitehouse6802e342008-05-21 17:03:22 +0100508/**
509 * do_xmote - Calls the DLM to change the state of a lock
510 * @gl: The lock state
511 * @gh: The holder (only for promotes)
512 * @target: The target lock state
513 *
514 */
515
516static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700517__releases(&gl->gl_spin)
518__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100519{
520 const struct gfs2_glock_operations *glops = gl->gl_ops;
521 struct gfs2_sbd *sdp = gl->gl_sbd;
522 unsigned int lck_flags = gh ? gh->gh_flags : 0;
523 int ret;
524
525 lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
526 LM_FLAG_PRIORITY);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000527 GLOCK_BUG_ON(gl, gl->gl_state == target);
528 GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100529 if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
530 glops->go_inval) {
531 set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
532 do_error(gl, 0); /* Fail queued try locks */
533 }
Steven Whitehouse47a25382010-11-30 15:49:31 +0000534 gl->gl_req = target;
Steven Whitehousea2457692012-01-20 10:38:36 +0000535 set_bit(GLF_BLOCKING, &gl->gl_flags);
536 if ((gl->gl_req == LM_ST_UNLOCKED) ||
537 (gl->gl_state == LM_ST_EXCLUSIVE) ||
538 (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
539 clear_bit(GLF_BLOCKING, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100540 spin_unlock(&gl->gl_spin);
Bob Peterson06dfc302012-10-24 14:41:05 -0400541 if (glops->go_sync)
542 glops->go_sync(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100543 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
544 glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
545 clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
546
547 gfs2_glock_hold(gl);
Steven Whitehouse921169c2010-11-29 12:50:38 +0000548 if (sdp->sd_lockstruct.ls_ops->lm_lock) {
549 /* lock_dlm */
550 ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
David Teiglanddba2d702012-11-14 13:46:53 -0500551 if (ret) {
552 printk(KERN_ERR "GFS2: lm_lock ret %d\n", ret);
553 GLOCK_BUG_ON(gl, 1);
554 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000555 } else { /* lock_nolock */
556 finish_xmote(gl, target);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100557 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
558 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100559 }
Steven Whitehouse921169c2010-11-29 12:50:38 +0000560
Steven Whitehouse6802e342008-05-21 17:03:22 +0100561 spin_lock(&gl->gl_spin);
562}
563
564/**
565 * find_first_holder - find the first "holder" gh
566 * @gl: the glock
567 */
568
569static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
570{
571 struct gfs2_holder *gh;
572
573 if (!list_empty(&gl->gl_holders)) {
574 gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
575 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
576 return gh;
577 }
578 return NULL;
579}
580
581/**
582 * run_queue - do all outstanding tasks related to a glock
583 * @gl: The glock in question
584 * @nonblock: True if we must not block in run_queue
585 *
586 */
587
588static void run_queue(struct gfs2_glock *gl, const int nonblock)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700589__releases(&gl->gl_spin)
590__acquires(&gl->gl_spin)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100591{
592 struct gfs2_holder *gh = NULL;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000593 int ret;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100594
595 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
596 return;
597
598 GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));
599
600 if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
601 gl->gl_demote_state != gl->gl_state) {
602 if (find_first_holder(gl))
Steven Whitehoused8348de2009-02-05 10:12:38 +0000603 goto out_unlock;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100604 if (nonblock)
605 goto out_sched;
606 set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100607 GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100608 gl->gl_target = gl->gl_demote_state;
609 } else {
610 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
611 gfs2_demote_wake(gl);
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000612 ret = do_promote(gl);
613 if (ret == 0)
Steven Whitehoused8348de2009-02-05 10:12:38 +0000614 goto out_unlock;
Steven Whitehouse813e0c42008-11-18 13:38:48 +0000615 if (ret == 2)
Steven Whitehousea228df62009-04-07 14:01:34 +0100616 goto out;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100617 gh = find_first_waiter(gl);
618 gl->gl_target = gh->gh_state;
619 if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
620 do_error(gl, 0); /* Fail queued try locks */
621 }
622 do_xmote(gl, gh, gl->gl_target);
Steven Whitehousea228df62009-04-07 14:01:34 +0100623out:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100624 return;
625
626out_sched:
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100627 clear_bit(GLF_LOCK, &gl->gl_flags);
628 smp_mb__after_clear_bit();
Steven Whitehouse6802e342008-05-21 17:03:22 +0100629 gfs2_glock_hold(gl);
630 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
Benjamin Marzinski8ff22a62009-07-10 18:04:24 -0500631 gfs2_glock_put_nolock(gl);
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100632 return;
633
Steven Whitehoused8348de2009-02-05 10:12:38 +0000634out_unlock:
Steven Whitehouse6802e342008-05-21 17:03:22 +0100635 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse7e71c552009-09-22 10:56:16 +0100636 smp_mb__after_clear_bit();
637 return;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100638}
639
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500640static void delete_work_func(struct work_struct *work)
641{
642 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete);
643 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000644 struct gfs2_inode *ip;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500645 struct inode *inode;
Steven Whitehouse044b9412010-11-03 20:01:07 +0000646 u64 no_addr = gl->gl_name.ln_number;
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500647
Steven Whitehouse044b9412010-11-03 20:01:07 +0000648 ip = gl->gl_object;
649 /* Note: Unsafe to dereference ip as we don't hold right refs/locks */
650
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500651 if (ip)
Steven Whitehouse4667a0e2011-04-18 14:18:09 +0100652 inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1);
Steven Whitehouse044b9412010-11-03 20:01:07 +0000653 else
654 inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED);
655 if (inode && !IS_ERR(inode)) {
656 d_prune_aliases(inode);
657 iput(inode);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500658 }
659 gfs2_glock_put(gl);
660}
661
Steven Whitehouse6802e342008-05-21 17:03:22 +0100662static void glock_work_func(struct work_struct *work)
663{
664 unsigned long delay = 0;
665 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000666 int drop_ref = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100667
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000668 if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100669 finish_xmote(gl, gl->gl_reply);
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000670 drop_ref = 1;
671 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100672 spin_lock(&gl->gl_spin);
Bob Petersonf90e5b52011-05-24 10:44:42 -0400673 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Steven Whitehouse265d529c2008-07-07 10:02:36 +0100674 gl->gl_state != LM_ST_UNLOCKED &&
675 gl->gl_demote_state != LM_ST_EXCLUSIVE) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100676 unsigned long holdtime, now = jiffies;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400677
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400678 holdtime = gl->gl_tchange + gl->gl_hold_time;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100679 if (time_before(now, holdtime))
680 delay = holdtime - now;
Bob Petersonf90e5b52011-05-24 10:44:42 -0400681
682 if (!delay) {
683 clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
684 set_bit(GLF_DEMOTE, &gl->gl_flags);
685 }
Steven Whitehouse6802e342008-05-21 17:03:22 +0100686 }
687 run_queue(gl, 0);
688 spin_unlock(&gl->gl_spin);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400689 if (!delay)
Steven Whitehouse6802e342008-05-21 17:03:22 +0100690 gfs2_glock_put(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400691 else {
692 if (gl->gl_name.ln_type != LM_TYPE_INODE)
693 delay = 0;
694 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
695 gfs2_glock_put(gl);
696 }
Steven Whitehouse26bb7502009-11-27 10:31:11 +0000697 if (drop_ref)
698 gfs2_glock_put(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100699}
700
David Teiglandb3b94fa2006-01-16 16:50:04 +0000701/**
702 * gfs2_glock_get() - Get a glock, or create one if one doesn't exist
703 * @sdp: The GFS2 superblock
704 * @number: the lock number
705 * @glops: The glock_operations to use
706 * @create: If 0, don't create the glock if it doesn't exist
707 * @glp: the glock is returned here
708 *
709 * This does not lock a glock, just finds/creates structures for one.
710 *
711 * Returns: errno
712 */
713
Steven Whitehousecd915492006-09-04 12:49:07 -0400714int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400715 const struct gfs2_glock_operations *glops, int create,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000716 struct gfs2_glock **glp)
717{
Steven Whitehouse009d8512009-12-08 12:12:13 +0000718 struct super_block *s = sdp->sd_vfs;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400719 struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type };
David Teiglandb3b94fa2006-01-16 16:50:04 +0000720 struct gfs2_glock *gl, *tmp;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400721 unsigned int hash = gl_hash(sdp, &name);
Steven Whitehouse009d8512009-12-08 12:12:13 +0000722 struct address_space *mapping;
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000723 struct kmem_cache *cachep;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000724
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000725 rcu_read_lock();
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400726 gl = search_bucket(hash, sdp, &name);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000727 rcu_read_unlock();
David Teiglandb3b94fa2006-01-16 16:50:04 +0000728
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000729 *glp = gl;
730 if (gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000731 return 0;
Steven Whitehouse64d576b2009-02-12 13:31:58 +0000732 if (!create)
733 return -ENOENT;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000734
Steven Whitehouse009d8512009-12-08 12:12:13 +0000735 if (glops->go_flags & GLOF_ASPACE)
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000736 cachep = gfs2_glock_aspace_cachep;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000737 else
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000738 cachep = gfs2_glock_cachep;
739 gl = kmem_cache_alloc(cachep, GFP_KERNEL);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000740 if (!gl)
741 return -ENOMEM;
742
David Teiglanddba2d702012-11-14 13:46:53 -0500743 memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
David Teiglanddba2d702012-11-14 13:46:53 -0500744
745 if (glops->go_flags & GLOF_LVB) {
David Teigland4e2f8842012-11-14 13:47:37 -0500746 gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_KERNEL);
747 if (!gl->gl_lksb.sb_lvbptr) {
David Teiglanddba2d702012-11-14 13:46:53 -0500748 kmem_cache_free(cachep, gl);
749 return -ENOMEM;
750 }
David Teiglanddba2d702012-11-14 13:46:53 -0500751 }
752
Steven Whitehouse8f052282010-01-29 15:21:27 +0000753 atomic_inc(&sdp->sd_glock_disposal);
Steven Whitehousea2457692012-01-20 10:38:36 +0000754 gl->gl_sbd = sdp;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400755 gl->gl_flags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000756 gl->gl_name = name;
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400757 atomic_set(&gl->gl_ref, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000758 gl->gl_state = LM_ST_UNLOCKED;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100759 gl->gl_target = LM_ST_UNLOCKED;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500760 gl->gl_demote_state = LM_ST_EXCLUSIVE;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400761 gl->gl_hash = hash;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000762 gl->gl_ops = glops;
Steven Whitehousea2457692012-01-20 10:38:36 +0000763 gl->gl_dstamp = ktime_set(0, 0);
764 preempt_disable();
765 /* We use the global stats to estimate the initial per-glock stats */
766 gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type];
767 preempt_enable();
768 gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0;
769 gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500770 gl->gl_tchange = jiffies;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400771 gl->gl_object = NULL;
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400772 gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500773 INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500774 INIT_WORK(&gl->gl_delete, delete_work_func);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000775
Steven Whitehouse009d8512009-12-08 12:12:13 +0000776 mapping = gfs2_glock2aspace(gl);
777 if (mapping) {
778 mapping->a_ops = &gfs2_meta_aops;
779 mapping->host = s->s_bdev->bd_inode;
780 mapping->flags = 0;
781 mapping_set_gfp_mask(mapping, GFP_NOFS);
Rafael Aquini252aa6f2012-12-11 16:02:35 -0800782 mapping->private_data = NULL;
Steven Whitehouse009d8512009-12-08 12:12:13 +0000783 mapping->backing_dev_info = s->s_bdi;
784 mapping->writeback_index = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000785 }
786
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000787 spin_lock_bucket(hash);
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400788 tmp = search_bucket(hash, sdp, &name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000789 if (tmp) {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000790 spin_unlock_bucket(hash);
David Teigland4e2f8842012-11-14 13:47:37 -0500791 kfree(gl->gl_lksb.sb_lvbptr);
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000792 kmem_cache_free(cachep, gl);
Steven Whitehousefc0e38d2011-03-09 10:58:04 +0000793 atomic_dec(&sdp->sd_glock_disposal);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000794 gl = tmp;
795 } else {
Steven Whitehousebc015cb2011-01-19 09:30:01 +0000796 hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]);
797 spin_unlock_bucket(hash);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000798 }
799
800 *glp = gl;
801
802 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000803}
804
805/**
806 * gfs2_holder_init - initialize a struct gfs2_holder in the default way
807 * @gl: the glock
808 * @state: the state we're requesting
809 * @flags: the modifier flags
810 * @gh: the holder structure
811 *
812 */
813
Steven Whitehouse190562b2006-04-20 16:57:23 -0400814void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000815 struct gfs2_holder *gh)
816{
817 INIT_LIST_HEAD(&gh->gh_list);
818 gh->gh_gl = gl;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500819 gh->gh_ip = (unsigned long)__builtin_return_address(0);
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800820 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000821 gh->gh_state = state;
822 gh->gh_flags = flags;
823 gh->gh_error = 0;
824 gh->gh_iflags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000825 gfs2_glock_hold(gl);
826}
827
828/**
829 * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it
830 * @state: the state we're requesting
831 * @flags: the modifier flags
832 * @gh: the holder structure
833 *
834 * Don't mess with the glock.
835 *
836 */
837
Steven Whitehouse190562b2006-04-20 16:57:23 -0400838void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000839{
840 gh->gh_state = state;
Steven Whitehouse579b78a2006-04-26 14:58:26 -0400841 gh->gh_flags = flags;
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000842 gh->gh_iflags = 0;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500843 gh->gh_ip = (unsigned long)__builtin_return_address(0);
Bob Peterson1a0eae82010-04-14 11:58:16 -0400844 if (gh->gh_owner_pid)
845 put_pid(gh->gh_owner_pid);
846 gh->gh_owner_pid = get_pid(task_pid(current));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000847}
848
849/**
850 * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
851 * @gh: the holder structure
852 *
853 */
854
855void gfs2_holder_uninit(struct gfs2_holder *gh)
856{
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800857 put_pid(gh->gh_owner_pid);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000858 gfs2_glock_put(gh->gh_gl);
859 gh->gh_gl = NULL;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500860 gh->gh_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000861}
862
Steven Whitehousefe64d512009-05-19 10:01:18 +0100863/**
864 * gfs2_glock_holder_wait
865 * @word: unused
866 *
867 * This function and gfs2_glock_demote_wait both show up in the WCHAN
868 * field. Thus I've separated these otherwise identical functions in
869 * order to be more informative to the user.
870 */
871
872static int gfs2_glock_holder_wait(void *word)
Steven Whitehousefee852e2007-01-17 15:33:23 +0000873{
874 schedule();
875 return 0;
876}
877
Steven Whitehousefe64d512009-05-19 10:01:18 +0100878static int gfs2_glock_demote_wait(void *word)
879{
880 schedule();
881 return 0;
882}
883
Bob Peterson07a79042012-08-09 12:48:44 -0500884/**
885 * gfs2_glock_wait - wait on a glock acquisition
886 * @gh: the glock holder
887 *
888 * Returns: 0 on success
889 */
890
891int gfs2_glock_wait(struct gfs2_holder *gh)
Steven Whitehousefee852e2007-01-17 15:33:23 +0000892{
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400893 unsigned long time1 = jiffies;
894
Steven Whitehousefee852e2007-01-17 15:33:23 +0000895 might_sleep();
Steven Whitehousefe64d512009-05-19 10:01:18 +0100896 wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -0400897 if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */
898 /* Lengthen the minimum hold time. */
899 gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time +
900 GL_GLOCK_HOLD_INCR,
901 GL_GLOCK_MAX_HOLD);
Bob Peterson07a79042012-08-09 12:48:44 -0500902 return gh->gh_error;
Abhijith Dasd93cfa92007-06-11 08:22:32 +0100903}
904
David Teiglandb3b94fa2006-01-16 16:50:04 +0000905/**
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000906 * handle_callback - process a demote request
David Teiglandb3b94fa2006-01-16 16:50:04 +0000907 * @gl: the glock
908 * @state: the state the caller wants us to change to
909 *
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000910 * There are only two requests that we are going to see in actual
911 * practise: LM_ST_SHARED and LM_ST_UNLOCKED
David Teiglandb3b94fa2006-01-16 16:50:04 +0000912 */
913
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500914static void handle_callback(struct gfs2_glock *gl, unsigned int state,
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100915 unsigned long delay, bool remote)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000916{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500917 int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE;
918
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -0500919 set_bit(bit, &gl->gl_flags);
920 if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
Steven Whitehouse3b8249f2007-03-16 09:40:31 +0000921 gl->gl_demote_state = state;
922 gl->gl_demote_time = jiffies;
Josef Whiter26caee52007-07-23 10:02:40 +0100923 } else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
924 gl->gl_demote_state != state) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100925 gl->gl_demote_state = LM_ST_UNLOCKED;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000926 }
Benjamin Marzinskib94a1702009-07-23 18:52:34 -0500927 if (gl->gl_ops->go_callback)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +0100928 gl->gl_ops->go_callback(gl, remote);
Steven Whitehouse7bd8b2e2013-04-10 10:32:05 +0100929 trace_gfs2_demote_rq(gl, remote);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000930}
931
Steven Whitehouse6802e342008-05-21 17:03:22 +0100932void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
Robert Peterson7c52b162007-03-16 10:26:37 +0000933{
Joe Perches5e690692010-11-09 16:35:20 -0800934 struct va_format vaf;
Robert Peterson7c52b162007-03-16 10:26:37 +0000935 va_list args;
936
937 va_start(args, fmt);
Joe Perches5e690692010-11-09 16:35:20 -0800938
Steven Whitehouse6802e342008-05-21 17:03:22 +0100939 if (seq) {
Steven Whitehouse1bb49302012-06-11 13:26:50 +0100940 seq_vprintf(seq, fmt, args);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100941 } else {
Joe Perches5e690692010-11-09 16:35:20 -0800942 vaf.fmt = fmt;
943 vaf.va = &args;
944
945 printk(KERN_ERR " %pV", &vaf);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100946 }
Joe Perches5e690692010-11-09 16:35:20 -0800947
Robert Peterson7c52b162007-03-16 10:26:37 +0000948 va_end(args);
949}
950
David Teiglandb3b94fa2006-01-16 16:50:04 +0000951/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000952 * add_to_queue - Add a holder to the wait queue (but look for recursion)
953 * @gh: the holder structure to add
954 *
Steven Whitehouse6802e342008-05-21 17:03:22 +0100955 * Eventually we should move the recursive locking trap to a
956 * debugging option or something like that. This is the fast
957 * path and needs to have the minimum number of distractions.
958 *
David Teiglandb3b94fa2006-01-16 16:50:04 +0000959 */
960
Steven Whitehouse6802e342008-05-21 17:03:22 +0100961static inline void add_to_queue(struct gfs2_holder *gh)
Harvey Harrison55ba4742008-10-24 11:31:12 -0700962__releases(&gl->gl_spin)
963__acquires(&gl->gl_spin)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000964{
965 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse6802e342008-05-21 17:03:22 +0100966 struct gfs2_sbd *sdp = gl->gl_sbd;
967 struct list_head *insert_pt = NULL;
968 struct gfs2_holder *gh2;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500969 int try_futile = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000970
Pavel Emelyanovb1e058d2008-02-07 00:13:19 -0800971 BUG_ON(gh->gh_owner_pid == NULL);
Steven Whitehousefee852e2007-01-17 15:33:23 +0000972 if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
973 BUG();
Steven Whitehouse190562b2006-04-20 16:57:23 -0400974
Steven Whitehouse6802e342008-05-21 17:03:22 +0100975 if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
976 if (test_bit(GLF_LOCK, &gl->gl_flags))
Bob Petersone5dc76b2012-08-09 12:48:46 -0500977 try_futile = !may_grant(gl, gh);
Steven Whitehouse6802e342008-05-21 17:03:22 +0100978 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
979 goto fail;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000980 }
981
Steven Whitehouse6802e342008-05-21 17:03:22 +0100982 list_for_each_entry(gh2, &gl->gl_holders, gh_list) {
983 if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
984 (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK)))
985 goto trap_recursive;
Bob Petersone5dc76b2012-08-09 12:48:46 -0500986 if (try_futile &&
987 !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
Steven Whitehouse6802e342008-05-21 17:03:22 +0100988fail:
989 gh->gh_error = GLR_TRYFAILED;
990 gfs2_holder_wake(gh);
991 return;
992 }
993 if (test_bit(HIF_HOLDER, &gh2->gh_iflags))
994 continue;
995 if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt))
996 insert_pt = &gh2->gh_list;
997 }
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +0100998 set_bit(GLF_QUEUED, &gl->gl_flags);
Steven Whitehouseedae38a2011-01-31 09:38:12 +0000999 trace_gfs2_glock_queue(gh, 1);
Steven Whitehousea2457692012-01-20 10:38:36 +00001000 gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
1001 gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001002 if (likely(insert_pt == NULL)) {
1003 list_add_tail(&gh->gh_list, &gl->gl_holders);
1004 if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
1005 goto do_cancel;
1006 return;
1007 }
1008 list_add_tail(&gh->gh_list, insert_pt);
1009do_cancel:
1010 gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
1011 if (!(gh->gh_flags & LM_FLAG_PRIORITY)) {
1012 spin_unlock(&gl->gl_spin);
Steven Whitehouse048bca22008-05-23 14:46:04 +01001013 if (sdp->sd_lockstruct.ls_ops->lm_cancel)
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001014 sdp->sd_lockstruct.ls_ops->lm_cancel(gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001015 spin_lock(&gl->gl_spin);
1016 }
1017 return;
1018
1019trap_recursive:
Joe Perches7af584d2012-12-12 10:19:08 -08001020 printk(KERN_ERR "original: %pSR\n", (void *)gh2->gh_ip);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001021 printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid));
1022 printk(KERN_ERR "lock type: %d req lock state : %d\n",
1023 gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
Joe Perches7af584d2012-12-12 10:19:08 -08001024 printk(KERN_ERR "new: %pSR\n", (void *)gh->gh_ip);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001025 printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid));
1026 printk(KERN_ERR "lock type: %d req lock state : %d\n",
1027 gh->gh_gl->gl_name.ln_type, gh->gh_state);
Steven Whitehouse8eae1ca2012-10-15 10:57:02 +01001028 gfs2_dump_glock(NULL, gl);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001029 BUG();
David Teiglandb3b94fa2006-01-16 16:50:04 +00001030}
1031
1032/**
1033 * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock)
1034 * @gh: the holder structure
1035 *
1036 * if (gh->gh_flags & GL_ASYNC), this never returns an error
1037 *
1038 * Returns: 0, GLR_TRYFAILED, or errno on failure
1039 */
1040
1041int gfs2_glock_nq(struct gfs2_holder *gh)
1042{
1043 struct gfs2_glock *gl = gh->gh_gl;
1044 struct gfs2_sbd *sdp = gl->gl_sbd;
1045 int error = 0;
1046
Steven Whitehouse6802e342008-05-21 17:03:22 +01001047 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001048 return -EIO;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001049
Steven Whitehousef42ab082011-04-14 16:50:31 +01001050 if (test_bit(GLF_LRU, &gl->gl_flags))
1051 gfs2_glock_remove_from_lru(gl);
1052
David Teiglandb3b94fa2006-01-16 16:50:04 +00001053 spin_lock(&gl->gl_spin);
1054 add_to_queue(gh);
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001055 if ((LM_FLAG_NOEXP & gh->gh_flags) &&
1056 test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
1057 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001058 run_queue(gl, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001059 spin_unlock(&gl->gl_spin);
1060
Steven Whitehouse6802e342008-05-21 17:03:22 +01001061 if (!(gh->gh_flags & GL_ASYNC))
1062 error = gfs2_glock_wait(gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001063
David Teiglandb3b94fa2006-01-16 16:50:04 +00001064 return error;
1065}
1066
1067/**
1068 * gfs2_glock_poll - poll to see if an async request has been completed
1069 * @gh: the holder
1070 *
1071 * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on
1072 */
1073
1074int gfs2_glock_poll(struct gfs2_holder *gh)
1075{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001076 return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001077}
1078
1079/**
1080 * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock)
1081 * @gh: the glock holder
1082 *
1083 */
1084
1085void gfs2_glock_dq(struct gfs2_holder *gh)
1086{
1087 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001088 const struct gfs2_glock_operations *glops = gl->gl_ops;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001089 unsigned delay = 0;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001090 int fast_path = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001091
Steven Whitehouse6802e342008-05-21 17:03:22 +01001092 spin_lock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001093 if (gh->gh_flags & GL_NOCACHE)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001094 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001095
David Teiglandb3b94fa2006-01-16 16:50:04 +00001096 list_del_init(&gh->gh_list);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001097 if (find_first_holder(gl) == NULL) {
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001098 if (glops->go_unlock) {
Steven Whitehouse6802e342008-05-21 17:03:22 +01001099 GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags));
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001100 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001101 glops->go_unlock(gh);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001102 spin_lock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001103 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse3042a2c2007-11-02 08:39:34 +00001104 }
Steven Whitehouse6802e342008-05-21 17:03:22 +01001105 if (list_empty(&gl->gl_holders) &&
1106 !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
1107 !test_bit(GLF_DEMOTE, &gl->gl_flags))
1108 fast_path = 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001109 }
Bob Peterson4abb6ad2012-08-09 12:48:43 -05001110 if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl))
1111 gfs2_glock_add_to_lru(gl);
1112
Steven Whitehouse63997772009-06-12 08:49:20 +01001113 trace_gfs2_glock_queue(gh, 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001114 spin_unlock(&gl->gl_spin);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001115 if (likely(fast_path))
1116 return;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001117
1118 gfs2_glock_hold(gl);
1119 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001120 !test_bit(GLF_DEMOTE, &gl->gl_flags) &&
1121 gl->gl_name.ln_type == LM_TYPE_INODE)
1122 delay = gl->gl_hold_time;
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001123 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1124 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001125}
1126
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001127void gfs2_glock_dq_wait(struct gfs2_holder *gh)
1128{
1129 struct gfs2_glock *gl = gh->gh_gl;
1130 gfs2_glock_dq(gh);
Bob Peterson81e1d452012-08-09 12:48:45 -05001131 might_sleep();
1132 wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE);
Abhijith Dasd93cfa92007-06-11 08:22:32 +01001133}
1134
David Teiglandb3b94fa2006-01-16 16:50:04 +00001135/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001136 * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
1137 * @gh: the holder structure
1138 *
1139 */
1140
1141void gfs2_glock_dq_uninit(struct gfs2_holder *gh)
1142{
1143 gfs2_glock_dq(gh);
1144 gfs2_holder_uninit(gh);
1145}
1146
1147/**
1148 * gfs2_glock_nq_num - acquire a glock based on lock number
1149 * @sdp: the filesystem
1150 * @number: the lock number
1151 * @glops: the glock operations for the type of glock
1152 * @state: the state to acquire the glock in
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001153 * @flags: modifier flags for the acquisition
David Teiglandb3b94fa2006-01-16 16:50:04 +00001154 * @gh: the struct gfs2_holder
1155 *
1156 * Returns: errno
1157 */
1158
Steven Whitehousecd915492006-09-04 12:49:07 -04001159int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001160 const struct gfs2_glock_operations *glops,
1161 unsigned int state, int flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001162{
1163 struct gfs2_glock *gl;
1164 int error;
1165
1166 error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
1167 if (!error) {
1168 error = gfs2_glock_nq_init(gl, state, flags, gh);
1169 gfs2_glock_put(gl);
1170 }
1171
1172 return error;
1173}
1174
1175/**
1176 * glock_compare - Compare two struct gfs2_glock structures for sorting
1177 * @arg_a: the first structure
1178 * @arg_b: the second structure
1179 *
1180 */
1181
1182static int glock_compare(const void *arg_a, const void *arg_b)
1183{
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001184 const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a;
1185 const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b;
1186 const struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1187 const struct lm_lockname *b = &gh_b->gh_gl->gl_name;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001188
1189 if (a->ln_number > b->ln_number)
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001190 return 1;
1191 if (a->ln_number < b->ln_number)
1192 return -1;
Steven Whitehouse1c0f4872007-01-22 12:10:39 -05001193 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 -04001194 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001195}
1196
1197/**
1198 * nq_m_sync - synchonously acquire more than one glock in deadlock free order
1199 * @num_gh: the number of structures
1200 * @ghs: an array of struct gfs2_holder structures
1201 *
1202 * Returns: 0 on success (all glocks acquired),
1203 * errno on failure (no glocks acquired)
1204 */
1205
1206static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs,
1207 struct gfs2_holder **p)
1208{
1209 unsigned int x;
1210 int error = 0;
1211
1212 for (x = 0; x < num_gh; x++)
1213 p[x] = &ghs[x];
1214
1215 sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL);
1216
1217 for (x = 0; x < num_gh; x++) {
1218 p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1219
1220 error = gfs2_glock_nq(p[x]);
1221 if (error) {
1222 while (x--)
1223 gfs2_glock_dq(p[x]);
1224 break;
1225 }
1226 }
1227
1228 return error;
1229}
1230
1231/**
1232 * gfs2_glock_nq_m - acquire multiple glocks
1233 * @num_gh: the number of structures
1234 * @ghs: an array of struct gfs2_holder structures
1235 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001236 *
1237 * Returns: 0 on success (all glocks acquired),
1238 * errno on failure (no glocks acquired)
1239 */
1240
1241int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1242{
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001243 struct gfs2_holder *tmp[4];
1244 struct gfs2_holder **pph = tmp;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001245 int error = 0;
1246
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001247 switch(num_gh) {
1248 case 0:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001249 return 0;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001250 case 1:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001251 ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1252 return gfs2_glock_nq(ghs);
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001253 default:
1254 if (num_gh <= 4)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001255 break;
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001256 pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS);
1257 if (!pph)
1258 return -ENOMEM;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001259 }
1260
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001261 error = nq_m_sync(num_gh, ghs, pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001262
Steven Whitehouseeaf5bd32007-06-19 15:38:17 +01001263 if (pph != tmp)
1264 kfree(pph);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001265
1266 return error;
1267}
1268
1269/**
1270 * gfs2_glock_dq_m - release multiple glocks
1271 * @num_gh: the number of structures
1272 * @ghs: an array of struct gfs2_holder structures
1273 *
1274 */
1275
1276void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1277{
Bob Petersonfa1bbde2011-03-10 11:41:57 -05001278 while (num_gh--)
1279 gfs2_glock_dq(&ghs[num_gh]);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001280}
1281
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001282void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
Steven Whitehouseda755fd2008-01-30 15:34:04 +00001283{
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001284 unsigned long delay = 0;
1285 unsigned long holdtime;
1286 unsigned long now = jiffies;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001287
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001288 gfs2_glock_hold(gl);
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001289 holdtime = gl->gl_tchange + gl->gl_hold_time;
1290 if (test_bit(GLF_QUEUED, &gl->gl_flags) &&
1291 gl->gl_name.ln_type == LM_TYPE_INODE) {
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001292 if (time_before(now, holdtime))
1293 delay = holdtime - now;
1294 if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001295 delay = gl->gl_hold_time;
Steven Whitehouse7b5e3d52010-09-03 09:39:20 +01001296 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001297
Steven Whitehouse6802e342008-05-21 17:03:22 +01001298 spin_lock(&gl->gl_spin);
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001299 handle_callback(gl, state, delay, true);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001300 spin_unlock(&gl->gl_spin);
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001301 if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
1302 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001303}
1304
1305/**
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001306 * gfs2_should_freeze - Figure out if glock should be frozen
1307 * @gl: The glock in question
1308 *
1309 * Glocks are not frozen if (a) the result of the dlm operation is
1310 * an error, (b) the locking operation was an unlock operation or
1311 * (c) if there is a "noexp" flagged request anywhere in the queue
1312 *
1313 * Returns: 1 if freezing should occur, 0 otherwise
1314 */
1315
1316static int gfs2_should_freeze(const struct gfs2_glock *gl)
1317{
1318 const struct gfs2_holder *gh;
1319
1320 if (gl->gl_reply & ~LM_OUT_ST_MASK)
1321 return 0;
1322 if (gl->gl_target == LM_ST_UNLOCKED)
1323 return 0;
1324
1325 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
1326 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
1327 continue;
1328 if (LM_FLAG_NOEXP & gh->gh_flags)
1329 return 0;
1330 }
1331
1332 return 1;
1333}
1334
1335/**
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001336 * gfs2_glock_complete - Callback used by locking
1337 * @gl: Pointer to the glock
1338 * @ret: The return value from the dlm
David Teiglandb3b94fa2006-01-16 16:50:04 +00001339 *
Steven Whitehouse47a25382010-11-30 15:49:31 +00001340 * The gl_reply field is under the gl_spin lock so that it is ok
1341 * to use a bitfield shared with other glock state fields.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001342 */
1343
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001344void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001345{
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001346 struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001347
Steven Whitehouse47a25382010-11-30 15:49:31 +00001348 spin_lock(&gl->gl_spin);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001349 gl->gl_reply = ret;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001350
David Teiglande0c2a9a2012-01-09 17:18:05 -05001351 if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001352 if (gfs2_should_freeze(gl)) {
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001353 set_bit(GLF_FROZEN, &gl->gl_flags);
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001354 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001355 return;
Steven Whitehouse0809f6e2010-08-02 10:15:17 +01001356 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001357 }
Steven Whitehouse47a25382010-11-30 15:49:31 +00001358
1359 spin_unlock(&gl->gl_spin);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001360 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
Steven Whitehouse47a25382010-11-30 15:49:31 +00001361 smp_wmb();
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001362 gfs2_glock_hold(gl);
1363 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1364 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001365}
1366
Steven Whitehouse4506a512013-02-01 20:36:03 +00001367static int glock_cmp(void *priv, struct list_head *a, struct list_head *b)
1368{
1369 struct gfs2_glock *gla, *glb;
1370
1371 gla = list_entry(a, struct gfs2_glock, gl_lru);
1372 glb = list_entry(b, struct gfs2_glock, gl_lru);
1373
1374 if (gla->gl_name.ln_number > glb->gl_name.ln_number)
1375 return 1;
1376 if (gla->gl_name.ln_number < glb->gl_name.ln_number)
1377 return -1;
1378
1379 return 0;
1380}
1381
1382/**
1383 * gfs2_dispose_glock_lru - Demote a list of glocks
1384 * @list: The list to dispose of
1385 *
1386 * Disposing of glocks may involve disk accesses, so that here we sort
1387 * the glocks by number (i.e. disk location of the inodes) so that if
1388 * there are any such accesses, they'll be sent in order (mostly).
1389 *
1390 * Must be called under the lru_lock, but may drop and retake this
1391 * lock. While the lru_lock is dropped, entries may vanish from the
1392 * list, but no new entries will appear on the list (since it is
1393 * private)
1394 */
1395
1396static void gfs2_dispose_glock_lru(struct list_head *list)
1397__releases(&lru_lock)
1398__acquires(&lru_lock)
1399{
1400 struct gfs2_glock *gl;
1401
1402 list_sort(NULL, list, glock_cmp);
1403
1404 while(!list_empty(list)) {
1405 gl = list_entry(list->next, struct gfs2_glock, gl_lru);
1406 list_del_init(&gl->gl_lru);
1407 clear_bit(GLF_LRU, &gl->gl_flags);
1408 gfs2_glock_hold(gl);
1409 spin_unlock(&lru_lock);
1410 spin_lock(&gl->gl_spin);
1411 if (demote_ok(gl))
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001412 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001413 WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
1414 smp_mb__after_clear_bit();
1415 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1416 gfs2_glock_put_nolock(gl);
1417 spin_unlock(&gl->gl_spin);
1418 spin_lock(&lru_lock);
1419 }
1420}
1421
Steven Whitehouse2a005852012-12-14 12:28:30 +00001422/**
1423 * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote
1424 * @nr: The number of entries to scan
1425 *
Steven Whitehouse4506a512013-02-01 20:36:03 +00001426 * This function selects the entries on the LRU which are able to
1427 * be demoted, and then kicks off the process by calling
1428 * gfs2_dispose_glock_lru() above.
Steven Whitehouse2a005852012-12-14 12:28:30 +00001429 */
David Teiglandb3b94fa2006-01-16 16:50:04 +00001430
Steven Whitehouse2a005852012-12-14 12:28:30 +00001431static void gfs2_scan_glock_lru(int nr)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001432{
1433 struct gfs2_glock *gl;
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001434 LIST_HEAD(skipped);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001435 LIST_HEAD(dispose);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001436
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001437 spin_lock(&lru_lock);
1438 while(nr && !list_empty(&lru_list)) {
1439 gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001440
1441 /* Test for being demotable */
1442 if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
Steven Whitehouse4506a512013-02-01 20:36:03 +00001443 list_move(&gl->gl_lru, &dispose);
1444 atomic_dec(&lru_count);
1445 nr--;
Steven Whitehouse2163b1e2009-06-25 16:30:26 +01001446 continue;
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001447 }
Steven Whitehouse4506a512013-02-01 20:36:03 +00001448
1449 list_move(&gl->gl_lru, &skipped);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001450 }
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001451 list_splice(&skipped, &lru_list);
Steven Whitehouse4506a512013-02-01 20:36:03 +00001452 if (!list_empty(&dispose))
1453 gfs2_dispose_glock_lru(&dispose);
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001454 spin_unlock(&lru_lock);
Steven Whitehouse2a005852012-12-14 12:28:30 +00001455}
1456
1457static int gfs2_shrink_glock_memory(struct shrinker *shrink,
1458 struct shrink_control *sc)
1459{
1460 if (sc->nr_to_scan) {
1461 if (!(sc->gfp_mask & __GFP_FS))
1462 return -1;
1463 gfs2_scan_glock_lru(sc->nr_to_scan);
1464 }
1465
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001466 return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001467}
1468
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001469static struct shrinker glock_shrinker = {
1470 .shrink = gfs2_shrink_glock_memory,
1471 .seeks = DEFAULT_SEEKS,
1472};
1473
David Teiglandb3b94fa2006-01-16 16:50:04 +00001474/**
1475 * examine_bucket - Call a function for glock in a hash bucket
1476 * @examiner: the function
1477 * @sdp: the filesystem
1478 * @bucket: the bucket
1479 *
David Teiglandb3b94fa2006-01-16 16:50:04 +00001480 */
1481
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001482static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp,
Steven Whitehouse37b2fa62006-09-08 13:35:56 -04001483 unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001484{
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001485 struct gfs2_glock *gl;
1486 struct hlist_bl_head *head = &gl_hash_table[hash];
1487 struct hlist_bl_node *pos;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001488
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001489 rcu_read_lock();
1490 hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) {
1491 if ((gl->gl_sbd == sdp) && atomic_read(&gl->gl_ref))
Steven Whitehouse24264432006-09-11 21:40:30 -04001492 examiner(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001493 }
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001494 rcu_read_unlock();
Steven Whitehouse8fbbfd22007-08-01 13:57:10 +01001495 cond_resched();
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001496}
1497
1498static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
1499{
1500 unsigned x;
1501
1502 for (x = 0; x < GFS2_GL_HASH_SIZE; x++)
1503 examine_bucket(examiner, sdp, x);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001504}
1505
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001506
1507/**
1508 * thaw_glock - thaw out a glock which has an unprocessed reply waiting
1509 * @gl: The glock to thaw
1510 *
1511 * N.B. When we freeze a glock, we leave a ref to the glock outstanding,
1512 * so this has to result in the ref count being dropped by one.
1513 */
1514
1515static void thaw_glock(struct gfs2_glock *gl)
1516{
1517 if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
1518 return;
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001519 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
1520 gfs2_glock_hold(gl);
1521 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1522 gfs2_glock_put(gl);
Steven Whitehousef057f6c2009-01-12 10:43:39 +00001523}
1524
David Teiglandb3b94fa2006-01-16 16:50:04 +00001525/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001526 * clear_glock - look at a glock and see if we can free it from glock cache
1527 * @gl: the glock to look at
1528 *
1529 */
1530
1531static void clear_glock(struct gfs2_glock *gl)
1532{
Steven Whitehousef42ab082011-04-14 16:50:31 +01001533 gfs2_glock_remove_from_lru(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001534
Steven Whitehouse6802e342008-05-21 17:03:22 +01001535 spin_lock(&gl->gl_spin);
Steven Whitehousec741c452010-09-29 14:20:52 +01001536 if (gl->gl_state != LM_ST_UNLOCKED)
Steven Whitehouse81ffbf62013-04-10 10:26:55 +01001537 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
Steven Whitehouse6802e342008-05-21 17:03:22 +01001538 spin_unlock(&gl->gl_spin);
1539 gfs2_glock_hold(gl);
1540 if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
1541 gfs2_glock_put(gl);
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),
Bob Peterson7cf8dcd2011-06-15 11:41:48 -04001746 atomic_read(&gl->gl_ref), 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);
Steven Whitehouse97cc1022008-11-20 13:39:47 +00001841 if (IS_ERR(glock_workqueue))
Benjamin Marzinskic4f68a12007-08-23 13:19:05 -05001842 return PTR_ERR(glock_workqueue);
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);
Benjamin Marzinskib94a1702009-07-23 18:52:34 -05001846 if (IS_ERR(gfs2_delete_workqueue)) {
1847 destroy_workqueue(glock_workqueue);
1848 return PTR_ERR(gfs2_delete_workqueue);
1849 }
Steven Whitehouse97cc1022008-11-20 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 Whitehouse97cc1022008-11-20 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 */
1902 } while (gi->sdp != gi->gl->gl_sbd || atomic_read(&gi->gl->gl_ref) == 0);
Abhijith Dasa947e032007-08-21 09:57:29 -05001903
Robert Peterson7c52b162007-03-16 10:26:37 +00001904 return 0;
1905}
1906
Steven Whitehouse6802e342008-05-21 17:03:22 +01001907static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
Robert Peterson7c52b162007-03-16 10:26:37 +00001908{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001909 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001910 loff_t n = *pos;
1911
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001912 if (gi->last_pos <= *pos)
1913 n = gi->nhash + (*pos - gi->last_pos);
1914 else
1915 gi->hash = 0;
1916
1917 gi->nhash = 0;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001918 rcu_read_lock();
Robert Peterson7c52b162007-03-16 10:26:37 +00001919
Steven Whitehouse6802e342008-05-21 17:03:22 +01001920 do {
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001921 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001922 return NULL;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001923 } while (n--);
Robert Peterson7c52b162007-03-16 10:26:37 +00001924
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001925 gi->last_pos = *pos;
Steven Whitehouse6802e342008-05-21 17:03:22 +01001926 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001927}
1928
Steven Whitehouse6802e342008-05-21 17:03:22 +01001929static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
Robert Peterson7c52b162007-03-16 10:26:37 +00001930 loff_t *pos)
1931{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001932 struct gfs2_glock_iter *gi = seq->private;
Robert Peterson7c52b162007-03-16 10:26:37 +00001933
1934 (*pos)++;
Steven Whitehouseba1ddcb2012-06-08 11:16:22 +01001935 gi->last_pos = *pos;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001936 if (gfs2_glock_iter_next(gi))
Robert Peterson7c52b162007-03-16 10:26:37 +00001937 return NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001938
Steven Whitehouse6802e342008-05-21 17:03:22 +01001939 return gi->gl;
Robert Peterson7c52b162007-03-16 10:26:37 +00001940}
1941
Steven Whitehouse6802e342008-05-21 17:03:22 +01001942static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001943{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001944 struct gfs2_glock_iter *gi = seq->private;
Steven Whitehousebc015cb2011-01-19 09:30:01 +00001945
1946 if (gi->gl)
1947 rcu_read_unlock();
1948 gi->gl = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00001949}
1950
Steven Whitehouse6802e342008-05-21 17:03:22 +01001951static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
Robert Peterson7c52b162007-03-16 10:26:37 +00001952{
Steven Whitehouse6802e342008-05-21 17:03:22 +01001953 return dump_glock(seq, iter_ptr);
Robert Peterson7c52b162007-03-16 10:26:37 +00001954}
1955
Steven Whitehousea2457692012-01-20 10:38:36 +00001956static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos)
1957{
1958 struct gfs2_glock_iter *gi = seq->private;
1959
1960 gi->hash = *pos;
1961 if (*pos >= GFS2_NR_SBSTATS)
1962 return NULL;
1963 preempt_disable();
1964 return SEQ_START_TOKEN;
1965}
1966
1967static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr,
1968 loff_t *pos)
1969{
1970 struct gfs2_glock_iter *gi = seq->private;
1971 (*pos)++;
1972 gi->hash++;
1973 if (gi->hash >= GFS2_NR_SBSTATS) {
1974 preempt_enable();
1975 return NULL;
1976 }
1977 return SEQ_START_TOKEN;
1978}
1979
1980static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
1981{
1982 preempt_enable();
1983}
1984
Denis Cheng4ef29002007-07-31 18:31:11 +08001985static const struct seq_operations gfs2_glock_seq_ops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00001986 .start = gfs2_glock_seq_start,
1987 .next = gfs2_glock_seq_next,
1988 .stop = gfs2_glock_seq_stop,
1989 .show = gfs2_glock_seq_show,
1990};
1991
Steven Whitehousea2457692012-01-20 10:38:36 +00001992static const struct seq_operations gfs2_glstats_seq_ops = {
1993 .start = gfs2_glock_seq_start,
1994 .next = gfs2_glock_seq_next,
1995 .stop = gfs2_glock_seq_stop,
1996 .show = gfs2_glstats_seq_show,
1997};
1998
1999static const struct seq_operations gfs2_sbstats_seq_ops = {
2000 .start = gfs2_sbstats_seq_start,
2001 .next = gfs2_sbstats_seq_next,
2002 .stop = gfs2_sbstats_seq_stop,
2003 .show = gfs2_sbstats_seq_show,
2004};
2005
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002006#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
2007
Steven Whitehousea2457692012-01-20 10:38:36 +00002008static int gfs2_glocks_open(struct inode *inode, struct file *file)
Robert Peterson7c52b162007-03-16 10:26:37 +00002009{
Steven Whitehouse6802e342008-05-21 17:03:22 +01002010 int ret = seq_open_private(file, &gfs2_glock_seq_ops,
2011 sizeof(struct gfs2_glock_iter));
2012 if (ret == 0) {
2013 struct seq_file *seq = file->private_data;
2014 struct gfs2_glock_iter *gi = seq->private;
2015 gi->sdp = inode->i_private;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002016 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01002017 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002018 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehouse6802e342008-05-21 17:03:22 +01002019 }
2020 return ret;
Robert Peterson7c52b162007-03-16 10:26:37 +00002021}
2022
Steven Whitehousea2457692012-01-20 10:38:36 +00002023static int gfs2_glstats_open(struct inode *inode, struct file *file)
2024{
2025 int ret = seq_open_private(file, &gfs2_glstats_seq_ops,
2026 sizeof(struct gfs2_glock_iter));
2027 if (ret == 0) {
2028 struct seq_file *seq = file->private_data;
2029 struct gfs2_glock_iter *gi = seq->private;
2030 gi->sdp = inode->i_private;
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002031 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
Steven Whitehousedf5d2f52012-06-07 13:30:16 +01002032 if (seq->buf)
Steven Whitehouse0fe2f1e2012-06-11 13:49:47 +01002033 seq->size = GFS2_SEQ_GOODSIZE;
Steven Whitehousea2457692012-01-20 10:38:36 +00002034 }
2035 return ret;
2036}
2037
2038static int gfs2_sbstats_open(struct inode *inode, struct file *file)
2039{
2040 int ret = seq_open_private(file, &gfs2_sbstats_seq_ops,
2041 sizeof(struct gfs2_glock_iter));
2042 if (ret == 0) {
2043 struct seq_file *seq = file->private_data;
2044 struct gfs2_glock_iter *gi = seq->private;
2045 gi->sdp = inode->i_private;
2046 }
2047 return ret;
2048}
2049
2050static const struct file_operations gfs2_glocks_fops = {
Robert Peterson7c52b162007-03-16 10:26:37 +00002051 .owner = THIS_MODULE,
Steven Whitehousea2457692012-01-20 10:38:36 +00002052 .open = gfs2_glocks_open,
2053 .read = seq_read,
2054 .llseek = seq_lseek,
2055 .release = seq_release_private,
2056};
2057
2058static const struct file_operations gfs2_glstats_fops = {
2059 .owner = THIS_MODULE,
2060 .open = gfs2_glstats_open,
2061 .read = seq_read,
2062 .llseek = seq_lseek,
2063 .release = seq_release_private,
2064};
2065
2066static const struct file_operations gfs2_sbstats_fops = {
2067 .owner = THIS_MODULE,
2068 .open = gfs2_sbstats_open,
Robert Peterson7c52b162007-03-16 10:26:37 +00002069 .read = seq_read,
2070 .llseek = seq_lseek,
Steven Whitehouse6802e342008-05-21 17:03:22 +01002071 .release = seq_release_private,
Robert Peterson7c52b162007-03-16 10:26:37 +00002072};
2073
2074int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
2075{
Robert Peterson5f882092007-04-18 11:41:11 -05002076 sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
2077 if (!sdp->debugfs_dir)
2078 return -ENOMEM;
2079 sdp->debugfs_dentry_glocks = debugfs_create_file("glocks",
2080 S_IFREG | S_IRUGO,
2081 sdp->debugfs_dir, sdp,
Steven Whitehousea2457692012-01-20 10:38:36 +00002082 &gfs2_glocks_fops);
Robert Peterson5f882092007-04-18 11:41:11 -05002083 if (!sdp->debugfs_dentry_glocks)
Steven Whitehousea2457692012-01-20 10:38:36 +00002084 goto fail;
2085
2086 sdp->debugfs_dentry_glstats = debugfs_create_file("glstats",
2087 S_IFREG | S_IRUGO,
2088 sdp->debugfs_dir, sdp,
2089 &gfs2_glstats_fops);
2090 if (!sdp->debugfs_dentry_glstats)
2091 goto fail;
2092
2093 sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats",
2094 S_IFREG | S_IRUGO,
2095 sdp->debugfs_dir, sdp,
2096 &gfs2_sbstats_fops);
2097 if (!sdp->debugfs_dentry_sbstats)
2098 goto fail;
Robert Peterson7c52b162007-03-16 10:26:37 +00002099
2100 return 0;
Steven Whitehousea2457692012-01-20 10:38:36 +00002101fail:
2102 gfs2_delete_debugfs_file(sdp);
2103 return -ENOMEM;
Robert Peterson7c52b162007-03-16 10:26:37 +00002104}
2105
2106void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
2107{
Steven Whitehousea2457692012-01-20 10:38:36 +00002108 if (sdp->debugfs_dir) {
Robert Peterson5f882092007-04-18 11:41:11 -05002109 if (sdp->debugfs_dentry_glocks) {
2110 debugfs_remove(sdp->debugfs_dentry_glocks);
2111 sdp->debugfs_dentry_glocks = NULL;
2112 }
Steven Whitehousea2457692012-01-20 10:38:36 +00002113 if (sdp->debugfs_dentry_glstats) {
2114 debugfs_remove(sdp->debugfs_dentry_glstats);
2115 sdp->debugfs_dentry_glstats = NULL;
2116 }
2117 if (sdp->debugfs_dentry_sbstats) {
2118 debugfs_remove(sdp->debugfs_dentry_sbstats);
2119 sdp->debugfs_dentry_sbstats = NULL;
2120 }
Robert Peterson5f882092007-04-18 11:41:11 -05002121 debugfs_remove(sdp->debugfs_dir);
2122 sdp->debugfs_dir = NULL;
2123 }
Robert Peterson7c52b162007-03-16 10:26:37 +00002124}
2125
2126int gfs2_register_debugfs(void)
2127{
2128 gfs2_root = debugfs_create_dir("gfs2", NULL);
2129 return gfs2_root ? 0 : -ENOMEM;
2130}
2131
2132void gfs2_unregister_debugfs(void)
2133{
2134 debugfs_remove(gfs2_root);
Robert Peterson5f882092007-04-18 11:41:11 -05002135 gfs2_root = NULL;
Robert Peterson7c52b162007-03-16 10:26:37 +00002136}