blob: 438146904b5839727ac2c378c5df87f574cfedaa [file] [log] [blame]
David Teiglandb3b94fa2006-01-16 16:50:04 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
Steven Whitehouse3a8a9a12006-05-18 15:09:15 -04003 * Copyright (C) 2004-2006 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>
13#include <linux/completion.h>
14#include <linux/buffer_head.h>
15#include <linux/delay.h>
16#include <linux/sort.h>
17#include <linux/jhash.h>
Steven Whitehoused0dc80d2006-03-29 14:36:49 -050018#include <linux/kallsyms.h>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050019#include <linux/gfs2_ondisk.h>
Steven Whitehouse24264432006-09-11 21:40:30 -040020#include <linux/list.h>
Fabio Massimo Di Nitto7d308592006-09-19 07:56:29 +020021#include <linux/lm_interface.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000022#include <asm/uaccess.h>
23
24#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050025#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000026#include "glock.h"
27#include "glops.h"
28#include "inode.h"
29#include "lm.h"
30#include "lops.h"
31#include "meta_io.h"
32#include "quota.h"
33#include "super.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050034#include "util.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000035
David Teiglandb3b94fa2006-01-16 16:50:04 +000036struct greedy {
37 struct gfs2_holder gr_gh;
David Howellsc4028952006-11-22 14:57:56 +000038 struct delayed_work gr_work;
David Teiglandb3b94fa2006-01-16 16:50:04 +000039};
40
Steven Whitehouse37b2fa62006-09-08 13:35:56 -040041struct gfs2_gl_hash_bucket {
Steven Whitehouseb6397892006-09-12 10:10:01 -040042 struct hlist_head hb_list;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -040043};
44
David Teiglandb3b94fa2006-01-16 16:50:04 +000045typedef void (*glock_examiner) (struct gfs2_glock * gl);
46
Adrian Bunk08bc2db2006-04-28 10:59:12 -040047static int gfs2_dump_lockstate(struct gfs2_sbd *sdp);
Steven Whitehouse320dd102006-05-18 16:25:27 -040048static int dump_glock(struct gfs2_glock *gl);
Steven Whitehouse24264432006-09-11 21:40:30 -040049static int dump_inode(struct gfs2_inode *ip);
Adrian Bunk08bc2db2006-04-28 10:59:12 -040050
Steven Whitehouseb6397892006-09-12 10:10:01 -040051#define GFS2_GL_HASH_SHIFT 15
Steven Whitehouse087efdd2006-09-09 16:59:11 -040052#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
53#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
54
Steven Whitehouse85d1da62006-09-07 14:40:21 -040055static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE];
Steven Whitehouse087efdd2006-09-09 16:59:11 -040056
57/*
58 * Despite what you might think, the numbers below are not arbitrary :-)
59 * They are taken from the ipv4 routing hash code, which is well tested
60 * and thus should be nearly optimal. Later on we might tweek the numbers
61 * but for now this should be fine.
62 *
63 * The reason for putting the locks in a separate array from the list heads
64 * is that we can have fewer locks than list heads and save memory. We use
65 * the same hash function for both, but with a different hash mask.
66 */
67#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
68 defined(CONFIG_PROVE_LOCKING)
69
70#ifdef CONFIG_LOCKDEP
71# define GL_HASH_LOCK_SZ 256
72#else
73# if NR_CPUS >= 32
74# define GL_HASH_LOCK_SZ 4096
75# elif NR_CPUS >= 16
76# define GL_HASH_LOCK_SZ 2048
77# elif NR_CPUS >= 8
78# define GL_HASH_LOCK_SZ 1024
79# elif NR_CPUS >= 4
80# define GL_HASH_LOCK_SZ 512
81# else
82# define GL_HASH_LOCK_SZ 256
83# endif
84#endif
85
86/* We never want more locks than chains */
87#if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ
88# undef GL_HASH_LOCK_SZ
89# define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE
90#endif
91
92static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ];
93
94static inline rwlock_t *gl_lock_addr(unsigned int x)
95{
Steven Whitehouse94610612006-09-09 18:59:27 -040096 return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)];
Steven Whitehouse087efdd2006-09-09 16:59:11 -040097}
98#else /* not SMP, so no spinlocks required */
Randy Dunlap0ac23062006-11-28 22:29:19 -080099static inline rwlock_t *gl_lock_addr(unsigned int x)
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400100{
101 return NULL;
102}
103#endif
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400104
David Teiglandb3b94fa2006-01-16 16:50:04 +0000105/**
106 * relaxed_state_ok - is a requested lock compatible with the current lock mode?
107 * @actual: the current state of the lock
108 * @requested: the lock state that was requested by the caller
109 * @flags: the modifier flags passed in by the caller
110 *
111 * Returns: 1 if the locks are compatible, 0 otherwise
112 */
113
114static inline int relaxed_state_ok(unsigned int actual, unsigned requested,
115 int flags)
116{
117 if (actual == requested)
118 return 1;
119
120 if (flags & GL_EXACT)
121 return 0;
122
123 if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED)
124 return 1;
125
126 if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY))
127 return 1;
128
129 return 0;
130}
131
132/**
133 * gl_hash() - Turn glock number into hash bucket number
134 * @lock: The glock number
135 *
136 * Returns: The number of the corresponding hash bucket
137 */
138
Steven Whitehouseb8547852006-09-07 13:12:27 -0400139static unsigned int gl_hash(const struct gfs2_sbd *sdp,
140 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000141{
142 unsigned int h;
143
Steven Whitehousecd915492006-09-04 12:49:07 -0400144 h = jhash(&name->ln_number, sizeof(u64), 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000145 h = jhash(&name->ln_type, sizeof(unsigned int), h);
Steven Whitehouseb8547852006-09-07 13:12:27 -0400146 h = jhash(&sdp, sizeof(struct gfs2_sbd *), h);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000147 h &= GFS2_GL_HASH_MASK;
148
149 return h;
150}
151
152/**
153 * glock_free() - Perform a few checks and then release struct gfs2_glock
154 * @gl: The glock to release
155 *
156 * Also calls lock module to release its internal structure for this glock.
157 *
158 */
159
160static void glock_free(struct gfs2_glock *gl)
161{
162 struct gfs2_sbd *sdp = gl->gl_sbd;
163 struct inode *aspace = gl->gl_aspace;
164
165 gfs2_lm_put_lock(sdp, gl->gl_lock);
166
167 if (aspace)
168 gfs2_aspace_put(aspace);
169
170 kmem_cache_free(gfs2_glock_cachep, gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000171}
172
173/**
174 * gfs2_glock_hold() - increment reference count on glock
175 * @gl: The glock to hold
176 *
177 */
178
179void gfs2_glock_hold(struct gfs2_glock *gl)
180{
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400181 atomic_inc(&gl->gl_ref);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000182}
183
184/**
185 * gfs2_glock_put() - Decrement reference count on glock
186 * @gl: The glock to put
187 *
188 */
189
190int gfs2_glock_put(struct gfs2_glock *gl)
191{
David Teiglandb3b94fa2006-01-16 16:50:04 +0000192 int rv = 0;
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400193 struct gfs2_sbd *sdp = gl->gl_sbd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000194
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400195 write_lock(gl_lock_addr(gl->gl_hash));
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400196 if (atomic_dec_and_test(&gl->gl_ref)) {
Steven Whitehouseb6397892006-09-12 10:10:01 -0400197 hlist_del(&gl->gl_list);
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400198 write_unlock(gl_lock_addr(gl->gl_hash));
Steven Whitehouse190562b2006-04-20 16:57:23 -0400199 BUG_ON(spin_is_locked(&gl->gl_spin));
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400200 gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED);
201 gfs2_assert(sdp, list_empty(&gl->gl_reclaim));
202 gfs2_assert(sdp, list_empty(&gl->gl_holders));
203 gfs2_assert(sdp, list_empty(&gl->gl_waiters1));
204 gfs2_assert(sdp, list_empty(&gl->gl_waiters2));
205 gfs2_assert(sdp, list_empty(&gl->gl_waiters3));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000206 glock_free(gl);
207 rv = 1;
208 goto out;
209 }
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400210 write_unlock(gl_lock_addr(gl->gl_hash));
Steven Whitehousea2242db2006-08-24 17:03:05 -0400211out:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000212 return rv;
213}
214
215/**
216 * queue_empty - check to see if a glock's queue is empty
217 * @gl: the glock
218 * @head: the head of the queue to check
219 *
220 * This function protects the list in the event that a process already
221 * has a holder on the list and is adding a second holder for itself.
222 * The glmutex lock is what generally prevents processes from working
223 * on the same glock at once, but the special case of adding a second
224 * holder for yourself ("recursive" locking) doesn't involve locking
225 * glmutex, making the spin lock necessary.
226 *
227 * Returns: 1 if the queue is empty
228 */
229
230static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head)
231{
232 int empty;
233 spin_lock(&gl->gl_spin);
234 empty = list_empty(head);
235 spin_unlock(&gl->gl_spin);
236 return empty;
237}
238
239/**
240 * search_bucket() - Find struct gfs2_glock by lock number
241 * @bucket: the bucket to search
242 * @name: The lock name
243 *
244 * Returns: NULL, or the struct gfs2_glock with the requested number
245 */
246
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400247static struct gfs2_glock *search_bucket(unsigned int hash,
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400248 const struct gfs2_sbd *sdp,
Steven Whitehoused6a53722006-08-30 11:16:23 -0400249 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000250{
251 struct gfs2_glock *gl;
Steven Whitehouseb6397892006-09-12 10:10:01 -0400252 struct hlist_node *h;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000253
Steven Whitehouseb6397892006-09-12 10:10:01 -0400254 hlist_for_each_entry(gl, h, &gl_hash_table[hash].hb_list, gl_list) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000255 if (!lm_name_equal(&gl->gl_name, name))
256 continue;
Steven Whitehouse899be4d2006-08-30 12:50:28 -0400257 if (gl->gl_sbd != sdp)
258 continue;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000259
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400260 atomic_inc(&gl->gl_ref);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000261
262 return gl;
263 }
264
265 return NULL;
266}
267
268/**
269 * gfs2_glock_find() - Find glock by lock number
270 * @sdp: The GFS2 superblock
271 * @name: The lock name
272 *
273 * Returns: NULL, or the struct gfs2_glock with the requested number
274 */
275
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400276static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp,
Steven Whitehoused6a53722006-08-30 11:16:23 -0400277 const struct lm_lockname *name)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000278{
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400279 unsigned int hash = gl_hash(sdp, name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000280 struct gfs2_glock *gl;
281
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400282 read_lock(gl_lock_addr(hash));
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400283 gl = search_bucket(hash, sdp, name);
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400284 read_unlock(gl_lock_addr(hash));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000285
286 return gl;
287}
288
289/**
290 * gfs2_glock_get() - Get a glock, or create one if one doesn't exist
291 * @sdp: The GFS2 superblock
292 * @number: the lock number
293 * @glops: The glock_operations to use
294 * @create: If 0, don't create the glock if it doesn't exist
295 * @glp: the glock is returned here
296 *
297 * This does not lock a glock, just finds/creates structures for one.
298 *
299 * Returns: errno
300 */
301
Steven Whitehousecd915492006-09-04 12:49:07 -0400302int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400303 const struct gfs2_glock_operations *glops, int create,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000304 struct gfs2_glock **glp)
305{
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400306 struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type };
David Teiglandb3b94fa2006-01-16 16:50:04 +0000307 struct gfs2_glock *gl, *tmp;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400308 unsigned int hash = gl_hash(sdp, &name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000309 int error;
310
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400311 read_lock(gl_lock_addr(hash));
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400312 gl = search_bucket(hash, sdp, &name);
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400313 read_unlock(gl_lock_addr(hash));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000314
315 if (gl || !create) {
316 *glp = gl;
317 return 0;
318 }
319
320 gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL);
321 if (!gl)
322 return -ENOMEM;
323
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400324 gl->gl_flags = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000325 gl->gl_name = name;
Steven Whitehouse16feb9f2006-09-13 10:43:37 -0400326 atomic_set(&gl->gl_ref, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000327 gl->gl_state = LM_ST_UNLOCKED;
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400328 gl->gl_hash = hash;
Steven Whitehouse320dd102006-05-18 16:25:27 -0400329 gl->gl_owner = NULL;
330 gl->gl_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000331 gl->gl_ops = glops;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400332 gl->gl_req_gh = NULL;
333 gl->gl_req_bh = NULL;
334 gl->gl_vn = 0;
335 gl->gl_stamp = jiffies;
336 gl->gl_object = NULL;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000337 gl->gl_sbd = sdp;
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400338 gl->gl_aspace = NULL;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000339 lops_init_le(&gl->gl_le, &gfs2_glock_lops);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000340
341 /* If this glock protects actual on-disk data or metadata blocks,
342 create a VFS inode to manage the pages/buffers holding them. */
Steven Whitehouse50299962006-09-04 09:49:55 -0400343 if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000344 gl->gl_aspace = gfs2_aspace_get(sdp);
345 if (!gl->gl_aspace) {
346 error = -ENOMEM;
347 goto fail;
348 }
349 }
350
351 error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock);
352 if (error)
353 goto fail_aspace;
354
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400355 write_lock(gl_lock_addr(hash));
Steven Whitehouse37b2fa62006-09-08 13:35:56 -0400356 tmp = search_bucket(hash, sdp, &name);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000357 if (tmp) {
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400358 write_unlock(gl_lock_addr(hash));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000359 glock_free(gl);
360 gl = tmp;
361 } else {
Steven Whitehouseb6397892006-09-12 10:10:01 -0400362 hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list);
Steven Whitehouse087efdd2006-09-09 16:59:11 -0400363 write_unlock(gl_lock_addr(hash));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000364 }
365
366 *glp = gl;
367
368 return 0;
369
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400370fail_aspace:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000371 if (gl->gl_aspace)
372 gfs2_aspace_put(gl->gl_aspace);
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400373fail:
Steven Whitehouse907b9bc2006-09-25 09:26:04 -0400374 kmem_cache_free(gfs2_glock_cachep, gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000375 return error;
376}
377
378/**
379 * gfs2_holder_init - initialize a struct gfs2_holder in the default way
380 * @gl: the glock
381 * @state: the state we're requesting
382 * @flags: the modifier flags
383 * @gh: the holder structure
384 *
385 */
386
Steven Whitehouse190562b2006-04-20 16:57:23 -0400387void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000388 struct gfs2_holder *gh)
389{
390 INIT_LIST_HEAD(&gh->gh_list);
391 gh->gh_gl = gl;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500392 gh->gh_ip = (unsigned long)__builtin_return_address(0);
Steven Whitehouse190562b2006-04-20 16:57:23 -0400393 gh->gh_owner = current;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000394 gh->gh_state = state;
395 gh->gh_flags = flags;
396 gh->gh_error = 0;
397 gh->gh_iflags = 0;
398 init_completion(&gh->gh_wait);
399
400 if (gh->gh_state == LM_ST_EXCLUSIVE)
401 gh->gh_flags |= GL_LOCAL_EXCL;
402
403 gfs2_glock_hold(gl);
404}
405
406/**
407 * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it
408 * @state: the state we're requesting
409 * @flags: the modifier flags
410 * @gh: the holder structure
411 *
412 * Don't mess with the glock.
413 *
414 */
415
Steven Whitehouse190562b2006-04-20 16:57:23 -0400416void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000417{
418 gh->gh_state = state;
Steven Whitehouse579b78a2006-04-26 14:58:26 -0400419 gh->gh_flags = flags;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000420 if (gh->gh_state == LM_ST_EXCLUSIVE)
421 gh->gh_flags |= GL_LOCAL_EXCL;
422
423 gh->gh_iflags &= 1 << HIF_ALLOCED;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500424 gh->gh_ip = (unsigned long)__builtin_return_address(0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000425}
426
427/**
428 * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
429 * @gh: the holder structure
430 *
431 */
432
433void gfs2_holder_uninit(struct gfs2_holder *gh)
434{
435 gfs2_glock_put(gh->gh_gl);
436 gh->gh_gl = NULL;
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500437 gh->gh_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000438}
439
440/**
441 * gfs2_holder_get - get a struct gfs2_holder structure
442 * @gl: the glock
443 * @state: the state we're requesting
444 * @flags: the modifier flags
Steven Whitehouseaf18ddb82006-06-24 15:42:21 -0400445 * @gfp_flags:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000446 *
447 * Figure out how big an impact this function has. Either:
448 * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd
449 * 2) Leave it like it is
450 *
451 * Returns: the holder structure, NULL on ENOMEM
452 */
453
Adrian Bunk08bc2db2006-04-28 10:59:12 -0400454static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl,
455 unsigned int state,
456 int flags, gfp_t gfp_flags)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000457{
458 struct gfs2_holder *gh;
459
460 gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags);
461 if (!gh)
462 return NULL;
463
464 gfs2_holder_init(gl, state, flags, gh);
465 set_bit(HIF_ALLOCED, &gh->gh_iflags);
Steven Whitehoused0dc80d2006-03-29 14:36:49 -0500466 gh->gh_ip = (unsigned long)__builtin_return_address(0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000467 return gh;
468}
469
470/**
471 * gfs2_holder_put - get rid of a struct gfs2_holder structure
472 * @gh: the holder structure
473 *
474 */
475
Adrian Bunk08bc2db2006-04-28 10:59:12 -0400476static void gfs2_holder_put(struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000477{
478 gfs2_holder_uninit(gh);
479 kfree(gh);
480}
481
482/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000483 * rq_mutex - process a mutex request in the queue
484 * @gh: the glock holder
485 *
486 * Returns: 1 if the queue is blocked
487 */
488
489static int rq_mutex(struct gfs2_holder *gh)
490{
491 struct gfs2_glock *gl = gh->gh_gl;
492
493 list_del_init(&gh->gh_list);
494 /* gh->gh_error never examined. */
495 set_bit(GLF_LOCK, &gl->gl_flags);
496 complete(&gh->gh_wait);
497
498 return 1;
499}
500
501/**
502 * rq_promote - process a promote request in the queue
503 * @gh: the glock holder
504 *
505 * Acquire a new inter-node lock, or change a lock state to more restrictive.
506 *
507 * Returns: 1 if the queue is blocked
508 */
509
510static int rq_promote(struct gfs2_holder *gh)
511{
512 struct gfs2_glock *gl = gh->gh_gl;
513 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400514 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000515
516 if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
517 if (list_empty(&gl->gl_holders)) {
518 gl->gl_req_gh = gh;
519 set_bit(GLF_LOCK, &gl->gl_flags);
520 spin_unlock(&gl->gl_spin);
521
522 if (atomic_read(&sdp->sd_reclaim_count) >
523 gfs2_tune_get(sdp, gt_reclaim_limit) &&
524 !(gh->gh_flags & LM_FLAG_PRIORITY)) {
525 gfs2_reclaim_glock(sdp);
526 gfs2_reclaim_glock(sdp);
527 }
528
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400529 glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000530 spin_lock(&gl->gl_spin);
531 }
532 return 1;
533 }
534
535 if (list_empty(&gl->gl_holders)) {
536 set_bit(HIF_FIRST, &gh->gh_iflags);
537 set_bit(GLF_LOCK, &gl->gl_flags);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000538 } else {
539 struct gfs2_holder *next_gh;
540 if (gh->gh_flags & GL_LOCAL_EXCL)
541 return 1;
542 next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder,
543 gh_list);
544 if (next_gh->gh_flags & GL_LOCAL_EXCL)
545 return 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000546 }
547
548 list_move_tail(&gh->gh_list, &gl->gl_holders);
549 gh->gh_error = 0;
550 set_bit(HIF_HOLDER, &gh->gh_iflags);
551
David Teiglandb3b94fa2006-01-16 16:50:04 +0000552 complete(&gh->gh_wait);
553
554 return 0;
555}
556
557/**
558 * rq_demote - process a demote request in the queue
559 * @gh: the glock holder
560 *
561 * Returns: 1 if the queue is blocked
562 */
563
564static int rq_demote(struct gfs2_holder *gh)
565{
566 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400567 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000568
569 if (!list_empty(&gl->gl_holders))
570 return 1;
571
572 if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) {
573 list_del_init(&gh->gh_list);
574 gh->gh_error = 0;
575 spin_unlock(&gl->gl_spin);
576 if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
577 gfs2_holder_put(gh);
578 else
579 complete(&gh->gh_wait);
580 spin_lock(&gl->gl_spin);
581 } else {
582 gl->gl_req_gh = gh;
583 set_bit(GLF_LOCK, &gl->gl_flags);
584 spin_unlock(&gl->gl_spin);
585
586 if (gh->gh_state == LM_ST_UNLOCKED ||
587 gl->gl_state != LM_ST_EXCLUSIVE)
588 glops->go_drop_th(gl);
589 else
590 glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
591
592 spin_lock(&gl->gl_spin);
593 }
594
595 return 0;
596}
597
598/**
599 * rq_greedy - process a queued request to drop greedy status
600 * @gh: the glock holder
601 *
602 * Returns: 1 if the queue is blocked
603 */
604
605static int rq_greedy(struct gfs2_holder *gh)
606{
607 struct gfs2_glock *gl = gh->gh_gl;
608
609 list_del_init(&gh->gh_list);
610 /* gh->gh_error never examined. */
611 clear_bit(GLF_GREEDY, &gl->gl_flags);
612 spin_unlock(&gl->gl_spin);
613
614 gfs2_holder_uninit(gh);
615 kfree(container_of(gh, struct greedy, gr_gh));
616
Steven Whitehouse907b9bc2006-09-25 09:26:04 -0400617 spin_lock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000618
619 return 0;
620}
621
622/**
623 * run_queue - process holder structures on a glock
624 * @gl: the glock
625 *
626 */
David Teiglandb3b94fa2006-01-16 16:50:04 +0000627static void run_queue(struct gfs2_glock *gl)
628{
629 struct gfs2_holder *gh;
630 int blocked = 1;
631
632 for (;;) {
633 if (test_bit(GLF_LOCK, &gl->gl_flags))
634 break;
635
636 if (!list_empty(&gl->gl_waiters1)) {
637 gh = list_entry(gl->gl_waiters1.next,
638 struct gfs2_holder, gh_list);
639
640 if (test_bit(HIF_MUTEX, &gh->gh_iflags))
641 blocked = rq_mutex(gh);
642 else
643 gfs2_assert_warn(gl->gl_sbd, 0);
644
645 } else if (!list_empty(&gl->gl_waiters2) &&
646 !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) {
647 gh = list_entry(gl->gl_waiters2.next,
648 struct gfs2_holder, gh_list);
649
650 if (test_bit(HIF_DEMOTE, &gh->gh_iflags))
651 blocked = rq_demote(gh);
652 else if (test_bit(HIF_GREEDY, &gh->gh_iflags))
653 blocked = rq_greedy(gh);
654 else
655 gfs2_assert_warn(gl->gl_sbd, 0);
656
657 } else if (!list_empty(&gl->gl_waiters3)) {
658 gh = list_entry(gl->gl_waiters3.next,
659 struct gfs2_holder, gh_list);
660
661 if (test_bit(HIF_PROMOTE, &gh->gh_iflags))
662 blocked = rq_promote(gh);
663 else
664 gfs2_assert_warn(gl->gl_sbd, 0);
665
666 } else
667 break;
668
669 if (blocked)
670 break;
671 }
672}
673
674/**
675 * gfs2_glmutex_lock - acquire a local lock on a glock
676 * @gl: the glock
677 *
678 * Gives caller exclusive access to manipulate a glock structure.
679 */
680
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400681static void gfs2_glmutex_lock(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000682{
683 struct gfs2_holder gh;
684
685 gfs2_holder_init(gl, 0, 0, &gh);
686 set_bit(HIF_MUTEX, &gh.gh_iflags);
687
688 spin_lock(&gl->gl_spin);
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400689 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000690 list_add_tail(&gh.gh_list, &gl->gl_waiters1);
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400691 } else {
Steven Whitehouse320dd102006-05-18 16:25:27 -0400692 gl->gl_owner = current;
693 gl->gl_ip = (unsigned long)__builtin_return_address(0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000694 complete(&gh.gh_wait);
Steven Whitehouse320dd102006-05-18 16:25:27 -0400695 }
David Teiglandb3b94fa2006-01-16 16:50:04 +0000696 spin_unlock(&gl->gl_spin);
697
698 wait_for_completion(&gh.gh_wait);
699 gfs2_holder_uninit(&gh);
700}
701
702/**
703 * gfs2_glmutex_trylock - try to acquire a local lock on a glock
704 * @gl: the glock
705 *
706 * Returns: 1 if the glock is acquired
707 */
708
Adrian Bunk08bc2db2006-04-28 10:59:12 -0400709static int gfs2_glmutex_trylock(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000710{
711 int acquired = 1;
712
713 spin_lock(&gl->gl_spin);
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400714 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000715 acquired = 0;
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400716 } else {
Steven Whitehouse320dd102006-05-18 16:25:27 -0400717 gl->gl_owner = current;
718 gl->gl_ip = (unsigned long)__builtin_return_address(0);
719 }
David Teiglandb3b94fa2006-01-16 16:50:04 +0000720 spin_unlock(&gl->gl_spin);
721
722 return acquired;
723}
724
725/**
726 * gfs2_glmutex_unlock - release a local lock on a glock
727 * @gl: the glock
728 *
729 */
730
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400731static void gfs2_glmutex_unlock(struct gfs2_glock *gl)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000732{
733 spin_lock(&gl->gl_spin);
734 clear_bit(GLF_LOCK, &gl->gl_flags);
Steven Whitehouse320dd102006-05-18 16:25:27 -0400735 gl->gl_owner = NULL;
736 gl->gl_ip = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000737 run_queue(gl);
Steven Whitehouse190562b2006-04-20 16:57:23 -0400738 BUG_ON(!spin_is_locked(&gl->gl_spin));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000739 spin_unlock(&gl->gl_spin);
740}
741
742/**
743 * handle_callback - add a demote request to a lock's queue
744 * @gl: the glock
745 * @state: the state the caller wants us to change to
746 *
Steven Whitehouseaf18ddb82006-06-24 15:42:21 -0400747 * Note: This may fail sliently if we are out of memory.
David Teiglandb3b94fa2006-01-16 16:50:04 +0000748 */
749
750static void handle_callback(struct gfs2_glock *gl, unsigned int state)
751{
752 struct gfs2_holder *gh, *new_gh = NULL;
753
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400754restart:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000755 spin_lock(&gl->gl_spin);
756
757 list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
758 if (test_bit(HIF_DEMOTE, &gh->gh_iflags) &&
759 gl->gl_req_gh != gh) {
760 if (gh->gh_state != state)
761 gh->gh_state = LM_ST_UNLOCKED;
762 goto out;
763 }
764 }
765
766 if (new_gh) {
767 list_add_tail(&new_gh->gh_list, &gl->gl_waiters2);
768 new_gh = NULL;
769 } else {
770 spin_unlock(&gl->gl_spin);
771
Steven Whitehouseab923032006-11-15 15:17:03 -0500772 new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_NOFS);
Steven Whitehouseaf18ddb82006-06-24 15:42:21 -0400773 if (!new_gh)
774 return;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000775 set_bit(HIF_DEMOTE, &new_gh->gh_iflags);
776 set_bit(HIF_DEALLOC, &new_gh->gh_iflags);
777
778 goto restart;
779 }
780
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400781out:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000782 spin_unlock(&gl->gl_spin);
783
784 if (new_gh)
785 gfs2_holder_put(new_gh);
786}
787
788/**
789 * state_change - record that the glock is now in a different state
790 * @gl: the glock
791 * @new_state the new state
792 *
793 */
794
795static void state_change(struct gfs2_glock *gl, unsigned int new_state)
796{
David Teiglandb3b94fa2006-01-16 16:50:04 +0000797 int held1, held2;
798
799 held1 = (gl->gl_state != LM_ST_UNLOCKED);
800 held2 = (new_state != LM_ST_UNLOCKED);
801
802 if (held1 != held2) {
David Teigland6a6b3d02006-02-23 10:11:47 +0000803 if (held2)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000804 gfs2_glock_hold(gl);
David Teigland6a6b3d02006-02-23 10:11:47 +0000805 else
David Teiglandb3b94fa2006-01-16 16:50:04 +0000806 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000807 }
808
809 gl->gl_state = new_state;
810}
811
812/**
813 * xmote_bh - Called after the lock module is done acquiring a lock
814 * @gl: The glock in question
815 * @ret: the int returned from the lock module
816 *
817 */
818
819static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
820{
821 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400822 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000823 struct gfs2_holder *gh = gl->gl_req_gh;
824 int prev_state = gl->gl_state;
825 int op_done = 1;
826
827 gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
828 gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
829 gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC));
830
831 state_change(gl, ret & LM_OUT_ST_MASK);
832
833 if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) {
834 if (glops->go_inval)
Steven Whitehouse1a14d3a2006-11-20 10:37:45 -0500835 glops->go_inval(gl, DIO_METADATA);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000836 } else if (gl->gl_state == LM_ST_DEFERRED) {
837 /* We might not want to do this here.
838 Look at moving to the inode glops. */
839 if (glops->go_inval)
Steven Whitehouse1a14d3a2006-11-20 10:37:45 -0500840 glops->go_inval(gl, 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000841 }
842
843 /* Deal with each possible exit condition */
844
845 if (!gh)
846 gl->gl_stamp = jiffies;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000847 else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
848 spin_lock(&gl->gl_spin);
849 list_del_init(&gh->gh_list);
850 gh->gh_error = -EIO;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000851 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000852 } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) {
853 spin_lock(&gl->gl_spin);
854 list_del_init(&gh->gh_list);
855 if (gl->gl_state == gh->gh_state ||
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400856 gl->gl_state == LM_ST_UNLOCKED) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000857 gh->gh_error = 0;
Steven Whitehouse85d1da62006-09-07 14:40:21 -0400858 } else {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000859 if (gfs2_assert_warn(sdp, gh->gh_flags &
860 (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1)
861 fs_warn(sdp, "ret = 0x%.8X\n", ret);
862 gh->gh_error = GLR_TRYFAILED;
863 }
864 spin_unlock(&gl->gl_spin);
865
866 if (ret & LM_OUT_CANCELED)
Steven Whitehouse50299962006-09-04 09:49:55 -0400867 handle_callback(gl, LM_ST_UNLOCKED);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000868
869 } else if (ret & LM_OUT_CANCELED) {
870 spin_lock(&gl->gl_spin);
871 list_del_init(&gh->gh_list);
872 gh->gh_error = GLR_CANCELED;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000873 spin_unlock(&gl->gl_spin);
874
875 } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
876 spin_lock(&gl->gl_spin);
877 list_move_tail(&gh->gh_list, &gl->gl_holders);
878 gh->gh_error = 0;
879 set_bit(HIF_HOLDER, &gh->gh_iflags);
880 spin_unlock(&gl->gl_spin);
881
882 set_bit(HIF_FIRST, &gh->gh_iflags);
883
884 op_done = 0;
885
886 } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
887 spin_lock(&gl->gl_spin);
888 list_del_init(&gh->gh_list);
889 gh->gh_error = GLR_TRYFAILED;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000890 spin_unlock(&gl->gl_spin);
891
892 } else {
893 if (gfs2_assert_withdraw(sdp, 0) == -1)
894 fs_err(sdp, "ret = 0x%.8X\n", ret);
895 }
896
897 if (glops->go_xmote_bh)
898 glops->go_xmote_bh(gl);
899
900 if (op_done) {
901 spin_lock(&gl->gl_spin);
902 gl->gl_req_gh = NULL;
903 gl->gl_req_bh = NULL;
904 clear_bit(GLF_LOCK, &gl->gl_flags);
905 run_queue(gl);
906 spin_unlock(&gl->gl_spin);
907 }
908
909 gfs2_glock_put(gl);
910
911 if (gh) {
912 if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
913 gfs2_holder_put(gh);
914 else
915 complete(&gh->gh_wait);
916 }
917}
918
919/**
920 * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock
921 * @gl: The glock in question
922 * @state: the requested state
923 * @flags: modifier flags to the lock call
924 *
925 */
926
927void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags)
928{
929 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400930 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000931 int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB |
932 LM_FLAG_NOEXP | LM_FLAG_ANY |
933 LM_FLAG_PRIORITY);
934 unsigned int lck_ret;
935
936 gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
937 gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
938 gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED);
939 gfs2_assert_warn(sdp, state != gl->gl_state);
940
Steven Whitehouse50299962006-09-04 09:49:55 -0400941 if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
Steven Whitehouse1a14d3a2006-11-20 10:37:45 -0500942 glops->go_sync(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000943
944 gfs2_glock_hold(gl);
945 gl->gl_req_bh = xmote_bh;
946
Steven Whitehouseec45d9f2006-08-30 10:36:52 -0400947 lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000948
949 if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR)))
950 return;
951
952 if (lck_ret & LM_OUT_ASYNC)
953 gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC);
954 else
955 xmote_bh(gl, lck_ret);
956}
957
958/**
959 * drop_bh - Called after a lock module unlock completes
960 * @gl: the glock
961 * @ret: the return status
962 *
963 * Doesn't wake up the process waiting on the struct gfs2_holder (if any)
964 * Doesn't drop the reference on the glock the top half took out
965 *
966 */
967
968static void drop_bh(struct gfs2_glock *gl, unsigned int ret)
969{
970 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -0400971 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000972 struct gfs2_holder *gh = gl->gl_req_gh;
973
974 clear_bit(GLF_PREFETCH, &gl->gl_flags);
975
976 gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
977 gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
978 gfs2_assert_warn(sdp, !ret);
979
980 state_change(gl, LM_ST_UNLOCKED);
981
982 if (glops->go_inval)
Steven Whitehouse1a14d3a2006-11-20 10:37:45 -0500983 glops->go_inval(gl, DIO_METADATA);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000984
985 if (gh) {
986 spin_lock(&gl->gl_spin);
987 list_del_init(&gh->gh_list);
988 gh->gh_error = 0;
989 spin_unlock(&gl->gl_spin);
990 }
991
992 if (glops->go_drop_bh)
993 glops->go_drop_bh(gl);
994
995 spin_lock(&gl->gl_spin);
996 gl->gl_req_gh = NULL;
997 gl->gl_req_bh = NULL;
998 clear_bit(GLF_LOCK, &gl->gl_flags);
999 run_queue(gl);
1000 spin_unlock(&gl->gl_spin);
1001
1002 gfs2_glock_put(gl);
1003
1004 if (gh) {
1005 if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
1006 gfs2_holder_put(gh);
1007 else
1008 complete(&gh->gh_wait);
1009 }
1010}
1011
1012/**
1013 * gfs2_glock_drop_th - call into the lock module to unlock a lock
1014 * @gl: the glock
1015 *
1016 */
1017
1018void gfs2_glock_drop_th(struct gfs2_glock *gl)
1019{
1020 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001021 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001022 unsigned int ret;
1023
1024 gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
1025 gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
1026 gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED);
1027
Steven Whitehouse50299962006-09-04 09:49:55 -04001028 if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
Steven Whitehouse1a14d3a2006-11-20 10:37:45 -05001029 glops->go_sync(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001030
1031 gfs2_glock_hold(gl);
1032 gl->gl_req_bh = drop_bh;
1033
David Teiglandb3b94fa2006-01-16 16:50:04 +00001034 ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state);
1035
1036 if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR)))
1037 return;
1038
1039 if (!ret)
1040 drop_bh(gl, ret);
1041 else
1042 gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC);
1043}
1044
1045/**
1046 * do_cancels - cancel requests for locks stuck waiting on an expire flag
1047 * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock
1048 *
1049 * Don't cancel GL_NOCANCEL requests.
1050 */
1051
1052static void do_cancels(struct gfs2_holder *gh)
1053{
1054 struct gfs2_glock *gl = gh->gh_gl;
1055
1056 spin_lock(&gl->gl_spin);
1057
1058 while (gl->gl_req_gh != gh &&
1059 !test_bit(HIF_HOLDER, &gh->gh_iflags) &&
1060 !list_empty(&gh->gh_list)) {
Steven Whitehouse50299962006-09-04 09:49:55 -04001061 if (gl->gl_req_bh && !(gl->gl_req_gh &&
1062 (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00001063 spin_unlock(&gl->gl_spin);
1064 gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock);
1065 msleep(100);
1066 spin_lock(&gl->gl_spin);
1067 } else {
1068 spin_unlock(&gl->gl_spin);
1069 msleep(100);
1070 spin_lock(&gl->gl_spin);
1071 }
1072 }
1073
1074 spin_unlock(&gl->gl_spin);
1075}
1076
1077/**
1078 * glock_wait_internal - wait on a glock acquisition
1079 * @gh: the glock holder
1080 *
1081 * Returns: 0 on success
1082 */
1083
1084static int glock_wait_internal(struct gfs2_holder *gh)
1085{
1086 struct gfs2_glock *gl = gh->gh_gl;
1087 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001088 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001089
1090 if (test_bit(HIF_ABORTED, &gh->gh_iflags))
1091 return -EIO;
1092
1093 if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
1094 spin_lock(&gl->gl_spin);
1095 if (gl->gl_req_gh != gh &&
1096 !test_bit(HIF_HOLDER, &gh->gh_iflags) &&
1097 !list_empty(&gh->gh_list)) {
1098 list_del_init(&gh->gh_list);
1099 gh->gh_error = GLR_TRYFAILED;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001100 run_queue(gl);
1101 spin_unlock(&gl->gl_spin);
1102 return gh->gh_error;
1103 }
1104 spin_unlock(&gl->gl_spin);
1105 }
1106
1107 if (gh->gh_flags & LM_FLAG_PRIORITY)
1108 do_cancels(gh);
1109
1110 wait_for_completion(&gh->gh_wait);
1111
1112 if (gh->gh_error)
1113 return gh->gh_error;
1114
1115 gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags));
Steven Whitehouse85d1da62006-09-07 14:40:21 -04001116 gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, gh->gh_state,
David Teiglandb3b94fa2006-01-16 16:50:04 +00001117 gh->gh_flags));
1118
1119 if (test_bit(HIF_FIRST, &gh->gh_iflags)) {
1120 gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
1121
1122 if (glops->go_lock) {
1123 gh->gh_error = glops->go_lock(gh);
1124 if (gh->gh_error) {
1125 spin_lock(&gl->gl_spin);
1126 list_del_init(&gh->gh_list);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001127 spin_unlock(&gl->gl_spin);
1128 }
1129 }
1130
1131 spin_lock(&gl->gl_spin);
1132 gl->gl_req_gh = NULL;
1133 gl->gl_req_bh = NULL;
1134 clear_bit(GLF_LOCK, &gl->gl_flags);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001135 run_queue(gl);
1136 spin_unlock(&gl->gl_spin);
1137 }
1138
1139 return gh->gh_error;
1140}
1141
1142static inline struct gfs2_holder *
1143find_holder_by_owner(struct list_head *head, struct task_struct *owner)
1144{
1145 struct gfs2_holder *gh;
1146
1147 list_for_each_entry(gh, head, gh_list) {
1148 if (gh->gh_owner == owner)
1149 return gh;
1150 }
1151
1152 return NULL;
1153}
1154
1155/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001156 * add_to_queue - Add a holder to the wait queue (but look for recursion)
1157 * @gh: the holder structure to add
1158 *
1159 */
1160
1161static void add_to_queue(struct gfs2_holder *gh)
1162{
1163 struct gfs2_glock *gl = gh->gh_gl;
1164 struct gfs2_holder *existing;
1165
Steven Whitehouse190562b2006-04-20 16:57:23 -04001166 BUG_ON(!gh->gh_owner);
1167
David Teiglandb3b94fa2006-01-16 16:50:04 +00001168 existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner);
1169 if (existing) {
Steven Whitehouse5965b1f2006-04-26 13:21:55 -04001170 print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
Abhijith Das86384602006-08-25 11:13:37 -05001171 printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid);
Steven Whitehouse907b9bc2006-09-25 09:26:04 -04001172 printk(KERN_INFO "lock type : %d lock state : %d\n",
Abhijith Das86384602006-08-25 11:13:37 -05001173 existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state);
Steven Whitehouse5965b1f2006-04-26 13:21:55 -04001174 print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
Abhijith Das86384602006-08-25 11:13:37 -05001175 printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid);
Steven Whitehouse907b9bc2006-09-25 09:26:04 -04001176 printk(KERN_INFO "lock type : %d lock state : %d\n",
Abhijith Das86384602006-08-25 11:13:37 -05001177 gl->gl_name.ln_type, gl->gl_state);
Steven Whitehouse5965b1f2006-04-26 13:21:55 -04001178 BUG();
David Teiglandb3b94fa2006-01-16 16:50:04 +00001179 }
1180
1181 existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner);
1182 if (existing) {
Steven Whitehouse5965b1f2006-04-26 13:21:55 -04001183 print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
1184 print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
1185 BUG();
David Teiglandb3b94fa2006-01-16 16:50:04 +00001186 }
1187
David Teiglandb3b94fa2006-01-16 16:50:04 +00001188 if (gh->gh_flags & LM_FLAG_PRIORITY)
1189 list_add(&gh->gh_list, &gl->gl_waiters3);
1190 else
Steven Whitehouse907b9bc2006-09-25 09:26:04 -04001191 list_add_tail(&gh->gh_list, &gl->gl_waiters3);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001192}
1193
1194/**
1195 * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock)
1196 * @gh: the holder structure
1197 *
1198 * if (gh->gh_flags & GL_ASYNC), this never returns an error
1199 *
1200 * Returns: 0, GLR_TRYFAILED, or errno on failure
1201 */
1202
1203int gfs2_glock_nq(struct gfs2_holder *gh)
1204{
1205 struct gfs2_glock *gl = gh->gh_gl;
1206 struct gfs2_sbd *sdp = gl->gl_sbd;
1207 int error = 0;
1208
Steven Whitehouse320dd102006-05-18 16:25:27 -04001209restart:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001210 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
1211 set_bit(HIF_ABORTED, &gh->gh_iflags);
1212 return -EIO;
1213 }
1214
1215 set_bit(HIF_PROMOTE, &gh->gh_iflags);
1216
1217 spin_lock(&gl->gl_spin);
1218 add_to_queue(gh);
1219 run_queue(gl);
1220 spin_unlock(&gl->gl_spin);
1221
1222 if (!(gh->gh_flags & GL_ASYNC)) {
1223 error = glock_wait_internal(gh);
1224 if (error == GLR_CANCELED) {
Steven Whitehouse190562b2006-04-20 16:57:23 -04001225 msleep(100);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001226 goto restart;
1227 }
1228 }
1229
1230 clear_bit(GLF_PREFETCH, &gl->gl_flags);
1231
1232 return error;
1233}
1234
1235/**
1236 * gfs2_glock_poll - poll to see if an async request has been completed
1237 * @gh: the holder
1238 *
1239 * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on
1240 */
1241
1242int gfs2_glock_poll(struct gfs2_holder *gh)
1243{
1244 struct gfs2_glock *gl = gh->gh_gl;
1245 int ready = 0;
1246
1247 spin_lock(&gl->gl_spin);
1248
1249 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
1250 ready = 1;
1251 else if (list_empty(&gh->gh_list)) {
1252 if (gh->gh_error == GLR_CANCELED) {
1253 spin_unlock(&gl->gl_spin);
Steven Whitehouse190562b2006-04-20 16:57:23 -04001254 msleep(100);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001255 if (gfs2_glock_nq(gh))
1256 return 1;
1257 return 0;
1258 } else
1259 ready = 1;
1260 }
1261
1262 spin_unlock(&gl->gl_spin);
1263
1264 return ready;
1265}
1266
1267/**
1268 * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC
1269 * @gh: the holder structure
1270 *
1271 * Returns: 0, GLR_TRYFAILED, or errno on failure
1272 */
1273
1274int gfs2_glock_wait(struct gfs2_holder *gh)
1275{
1276 int error;
1277
1278 error = glock_wait_internal(gh);
1279 if (error == GLR_CANCELED) {
Steven Whitehouse190562b2006-04-20 16:57:23 -04001280 msleep(100);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001281 gh->gh_flags &= ~GL_ASYNC;
1282 error = gfs2_glock_nq(gh);
1283 }
1284
1285 return error;
1286}
1287
1288/**
1289 * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock)
1290 * @gh: the glock holder
1291 *
1292 */
1293
1294void gfs2_glock_dq(struct gfs2_holder *gh)
1295{
1296 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001297 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001298
David Teiglandb3b94fa2006-01-16 16:50:04 +00001299 if (gh->gh_flags & GL_NOCACHE)
1300 handle_callback(gl, LM_ST_UNLOCKED);
1301
1302 gfs2_glmutex_lock(gl);
1303
1304 spin_lock(&gl->gl_spin);
1305 list_del_init(&gh->gh_list);
1306
1307 if (list_empty(&gl->gl_holders)) {
1308 spin_unlock(&gl->gl_spin);
1309
1310 if (glops->go_unlock)
1311 glops->go_unlock(gh);
1312
David Teiglandb3b94fa2006-01-16 16:50:04 +00001313 gl->gl_stamp = jiffies;
1314
1315 spin_lock(&gl->gl_spin);
1316 }
1317
1318 clear_bit(GLF_LOCK, &gl->gl_flags);
1319 run_queue(gl);
1320 spin_unlock(&gl->gl_spin);
1321}
1322
1323/**
1324 * gfs2_glock_prefetch - Try to prefetch a glock
1325 * @gl: the glock
1326 * @state: the state to prefetch in
1327 * @flags: flags passed to go_xmote_th()
1328 *
1329 */
1330
Adrian Bunk08bc2db2006-04-28 10:59:12 -04001331static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state,
1332 int flags)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001333{
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001334 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001335
1336 spin_lock(&gl->gl_spin);
1337
Steven Whitehouse50299962006-09-04 09:49:55 -04001338 if (test_bit(GLF_LOCK, &gl->gl_flags) || !list_empty(&gl->gl_holders) ||
1339 !list_empty(&gl->gl_waiters1) || !list_empty(&gl->gl_waiters2) ||
David Teiglandb3b94fa2006-01-16 16:50:04 +00001340 !list_empty(&gl->gl_waiters3) ||
1341 relaxed_state_ok(gl->gl_state, state, flags)) {
1342 spin_unlock(&gl->gl_spin);
1343 return;
1344 }
1345
1346 set_bit(GLF_PREFETCH, &gl->gl_flags);
1347 set_bit(GLF_LOCK, &gl->gl_flags);
1348 spin_unlock(&gl->gl_spin);
1349
1350 glops->go_xmote_th(gl, state, flags);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001351}
1352
David Howellsc4028952006-11-22 14:57:56 +00001353static void greedy_work(struct work_struct *work)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001354{
David Howellsc4028952006-11-22 14:57:56 +00001355 struct greedy *gr = container_of(work, struct greedy, gr_work.work);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001356 struct gfs2_holder *gh = &gr->gr_gh;
1357 struct gfs2_glock *gl = gh->gh_gl;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001358 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001359
1360 clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
1361
1362 if (glops->go_greedy)
1363 glops->go_greedy(gl);
1364
1365 spin_lock(&gl->gl_spin);
1366
1367 if (list_empty(&gl->gl_waiters2)) {
1368 clear_bit(GLF_GREEDY, &gl->gl_flags);
1369 spin_unlock(&gl->gl_spin);
1370 gfs2_holder_uninit(gh);
1371 kfree(gr);
1372 } else {
1373 gfs2_glock_hold(gl);
1374 list_add_tail(&gh->gh_list, &gl->gl_waiters2);
1375 run_queue(gl);
1376 spin_unlock(&gl->gl_spin);
1377 gfs2_glock_put(gl);
1378 }
1379}
1380
1381/**
1382 * gfs2_glock_be_greedy -
1383 * @gl:
1384 * @time:
1385 *
1386 * Returns: 0 if go_greedy will be called, 1 otherwise
1387 */
1388
1389int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time)
1390{
1391 struct greedy *gr;
1392 struct gfs2_holder *gh;
1393
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -04001394 if (!time || gl->gl_sbd->sd_args.ar_localcaching ||
David Teiglandb3b94fa2006-01-16 16:50:04 +00001395 test_and_set_bit(GLF_GREEDY, &gl->gl_flags))
1396 return 1;
1397
1398 gr = kmalloc(sizeof(struct greedy), GFP_KERNEL);
1399 if (!gr) {
1400 clear_bit(GLF_GREEDY, &gl->gl_flags);
1401 return 1;
1402 }
1403 gh = &gr->gr_gh;
1404
Steven Whitehouse579b78a2006-04-26 14:58:26 -04001405 gfs2_holder_init(gl, 0, 0, gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001406 set_bit(HIF_GREEDY, &gh->gh_iflags);
David Howellsc4028952006-11-22 14:57:56 +00001407 INIT_DELAYED_WORK(&gr->gr_work, greedy_work);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001408
1409 set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
1410 schedule_delayed_work(&gr->gr_work, time);
1411
1412 return 0;
1413}
1414
1415/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001416 * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
1417 * @gh: the holder structure
1418 *
1419 */
1420
1421void gfs2_glock_dq_uninit(struct gfs2_holder *gh)
1422{
1423 gfs2_glock_dq(gh);
1424 gfs2_holder_uninit(gh);
1425}
1426
1427/**
1428 * gfs2_glock_nq_num - acquire a glock based on lock number
1429 * @sdp: the filesystem
1430 * @number: the lock number
1431 * @glops: the glock operations for the type of glock
1432 * @state: the state to acquire the glock in
1433 * @flags: modifier flags for the aquisition
1434 * @gh: the struct gfs2_holder
1435 *
1436 * Returns: errno
1437 */
1438
Steven Whitehousecd915492006-09-04 12:49:07 -04001439int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001440 const struct gfs2_glock_operations *glops,
1441 unsigned int state, int flags, struct gfs2_holder *gh)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001442{
1443 struct gfs2_glock *gl;
1444 int error;
1445
1446 error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
1447 if (!error) {
1448 error = gfs2_glock_nq_init(gl, state, flags, gh);
1449 gfs2_glock_put(gl);
1450 }
1451
1452 return error;
1453}
1454
1455/**
1456 * glock_compare - Compare two struct gfs2_glock structures for sorting
1457 * @arg_a: the first structure
1458 * @arg_b: the second structure
1459 *
1460 */
1461
1462static int glock_compare(const void *arg_a, const void *arg_b)
1463{
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001464 const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a;
1465 const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b;
1466 const struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1467 const struct lm_lockname *b = &gh_b->gh_gl->gl_name;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001468
1469 if (a->ln_number > b->ln_number)
Steven Whitehousea5e08a92006-09-09 17:07:05 -04001470 return 1;
1471 if (a->ln_number < b->ln_number)
1472 return -1;
1473 if (gh_a->gh_state == LM_ST_SHARED && gh_b->gh_state == LM_ST_EXCLUSIVE)
1474 return 1;
1475 if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && (gh_b->gh_flags & GL_LOCAL_EXCL))
1476 return 1;
1477 return 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001478}
1479
1480/**
1481 * nq_m_sync - synchonously acquire more than one glock in deadlock free order
1482 * @num_gh: the number of structures
1483 * @ghs: an array of struct gfs2_holder structures
1484 *
1485 * Returns: 0 on success (all glocks acquired),
1486 * errno on failure (no glocks acquired)
1487 */
1488
1489static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs,
1490 struct gfs2_holder **p)
1491{
1492 unsigned int x;
1493 int error = 0;
1494
1495 for (x = 0; x < num_gh; x++)
1496 p[x] = &ghs[x];
1497
1498 sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL);
1499
1500 for (x = 0; x < num_gh; x++) {
1501 p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1502
1503 error = gfs2_glock_nq(p[x]);
1504 if (error) {
1505 while (x--)
1506 gfs2_glock_dq(p[x]);
1507 break;
1508 }
1509 }
1510
1511 return error;
1512}
1513
1514/**
1515 * gfs2_glock_nq_m - acquire multiple glocks
1516 * @num_gh: the number of structures
1517 * @ghs: an array of struct gfs2_holder structures
1518 *
1519 * Figure out how big an impact this function has. Either:
1520 * 1) Replace this code with code that calls gfs2_glock_prefetch()
1521 * 2) Forget async stuff and just call nq_m_sync()
1522 * 3) Leave it like it is
1523 *
1524 * Returns: 0 on success (all glocks acquired),
1525 * errno on failure (no glocks acquired)
1526 */
1527
1528int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1529{
1530 int *e;
1531 unsigned int x;
1532 int borked = 0, serious = 0;
1533 int error = 0;
1534
1535 if (!num_gh)
1536 return 0;
1537
1538 if (num_gh == 1) {
1539 ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1540 return gfs2_glock_nq(ghs);
1541 }
1542
1543 e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL);
1544 if (!e)
1545 return -ENOMEM;
1546
1547 for (x = 0; x < num_gh; x++) {
1548 ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC;
1549 error = gfs2_glock_nq(&ghs[x]);
1550 if (error) {
1551 borked = 1;
1552 serious = error;
1553 num_gh = x;
1554 break;
1555 }
1556 }
1557
1558 for (x = 0; x < num_gh; x++) {
1559 error = e[x] = glock_wait_internal(&ghs[x]);
1560 if (error) {
1561 borked = 1;
1562 if (error != GLR_TRYFAILED && error != GLR_CANCELED)
1563 serious = error;
1564 }
1565 }
1566
1567 if (!borked) {
1568 kfree(e);
1569 return 0;
1570 }
1571
1572 for (x = 0; x < num_gh; x++)
1573 if (!e[x])
1574 gfs2_glock_dq(&ghs[x]);
1575
1576 if (serious)
1577 error = serious;
1578 else {
1579 for (x = 0; x < num_gh; x++)
1580 gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags,
1581 &ghs[x]);
1582 error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e);
1583 }
1584
1585 kfree(e);
1586
1587 return error;
1588}
1589
1590/**
1591 * gfs2_glock_dq_m - release multiple glocks
1592 * @num_gh: the number of structures
1593 * @ghs: an array of struct gfs2_holder structures
1594 *
1595 */
1596
1597void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1598{
1599 unsigned int x;
1600
1601 for (x = 0; x < num_gh; x++)
1602 gfs2_glock_dq(&ghs[x]);
1603}
1604
1605/**
1606 * gfs2_glock_dq_uninit_m - release multiple glocks
1607 * @num_gh: the number of structures
1608 * @ghs: an array of struct gfs2_holder structures
1609 *
1610 */
1611
1612void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs)
1613{
1614 unsigned int x;
1615
1616 for (x = 0; x < num_gh; x++)
1617 gfs2_glock_dq_uninit(&ghs[x]);
1618}
1619
1620/**
1621 * gfs2_glock_prefetch_num - prefetch a glock based on lock number
1622 * @sdp: the filesystem
1623 * @number: the lock number
1624 * @glops: the glock operations for the type of glock
1625 * @state: the state to acquire the glock in
1626 * @flags: modifier flags for the aquisition
1627 *
1628 * Returns: errno
1629 */
1630
Steven Whitehousecd915492006-09-04 12:49:07 -04001631void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, u64 number,
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001632 const struct gfs2_glock_operations *glops,
David Teiglandb3b94fa2006-01-16 16:50:04 +00001633 unsigned int state, int flags)
1634{
1635 struct gfs2_glock *gl;
1636 int error;
1637
1638 if (atomic_read(&sdp->sd_reclaim_count) <
1639 gfs2_tune_get(sdp, gt_reclaim_limit)) {
1640 error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
1641 if (!error) {
1642 gfs2_glock_prefetch(gl, state, flags);
1643 gfs2_glock_put(gl);
1644 }
1645 }
1646}
1647
1648/**
1649 * gfs2_lvb_hold - attach a LVB from a glock
1650 * @gl: The glock in question
1651 *
1652 */
1653
1654int gfs2_lvb_hold(struct gfs2_glock *gl)
1655{
1656 int error;
1657
1658 gfs2_glmutex_lock(gl);
1659
1660 if (!atomic_read(&gl->gl_lvb_count)) {
1661 error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb);
1662 if (error) {
1663 gfs2_glmutex_unlock(gl);
1664 return error;
1665 }
1666 gfs2_glock_hold(gl);
1667 }
1668 atomic_inc(&gl->gl_lvb_count);
1669
1670 gfs2_glmutex_unlock(gl);
1671
1672 return 0;
1673}
1674
1675/**
1676 * gfs2_lvb_unhold - detach a LVB from a glock
1677 * @gl: The glock in question
1678 *
1679 */
1680
1681void gfs2_lvb_unhold(struct gfs2_glock *gl)
1682{
1683 gfs2_glock_hold(gl);
1684 gfs2_glmutex_lock(gl);
1685
1686 gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0);
1687 if (atomic_dec_and_test(&gl->gl_lvb_count)) {
1688 gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb);
1689 gl->gl_lvb = NULL;
1690 gfs2_glock_put(gl);
1691 }
1692
1693 gfs2_glmutex_unlock(gl);
1694 gfs2_glock_put(gl);
1695}
1696
David Teiglandb3b94fa2006-01-16 16:50:04 +00001697static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name,
1698 unsigned int state)
1699{
1700 struct gfs2_glock *gl;
1701
1702 gl = gfs2_glock_find(sdp, name);
1703 if (!gl)
1704 return;
1705
1706 if (gl->gl_ops->go_callback)
1707 gl->gl_ops->go_callback(gl, state);
1708 handle_callback(gl, state);
1709
1710 spin_lock(&gl->gl_spin);
1711 run_queue(gl);
1712 spin_unlock(&gl->gl_spin);
1713
1714 gfs2_glock_put(gl);
1715}
1716
1717/**
1718 * gfs2_glock_cb - Callback used by locking module
Steven Whitehouse1c089c32006-09-07 15:50:20 -04001719 * @sdp: Pointer to the superblock
David Teiglandb3b94fa2006-01-16 16:50:04 +00001720 * @type: Type of callback
1721 * @data: Type dependent data pointer
1722 *
1723 * Called by the locking module when it wants to tell us something.
1724 * Either we need to drop a lock, one of our ASYNC requests completed, or
1725 * a journal from another client needs to be recovered.
1726 */
1727
Steven Whitehouse9b47c112006-09-08 10:17:58 -04001728void gfs2_glock_cb(void *cb_data, unsigned int type, void *data)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001729{
Steven Whitehouse9b47c112006-09-08 10:17:58 -04001730 struct gfs2_sbd *sdp = cb_data;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001731
David Teiglandb3b94fa2006-01-16 16:50:04 +00001732 switch (type) {
1733 case LM_CB_NEED_E:
David Teiglande7f5c012006-04-27 11:25:45 -04001734 blocking_cb(sdp, data, LM_ST_UNLOCKED);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001735 return;
1736
1737 case LM_CB_NEED_D:
David Teiglande7f5c012006-04-27 11:25:45 -04001738 blocking_cb(sdp, data, LM_ST_DEFERRED);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001739 return;
1740
1741 case LM_CB_NEED_S:
David Teiglande7f5c012006-04-27 11:25:45 -04001742 blocking_cb(sdp, data, LM_ST_SHARED);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001743 return;
1744
1745 case LM_CB_ASYNC: {
David Teiglande7f5c012006-04-27 11:25:45 -04001746 struct lm_async_cb *async = data;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001747 struct gfs2_glock *gl;
1748
1749 gl = gfs2_glock_find(sdp, &async->lc_name);
1750 if (gfs2_assert_warn(sdp, gl))
1751 return;
1752 if (!gfs2_assert_warn(sdp, gl->gl_req_bh))
1753 gl->gl_req_bh(gl, async->lc_ret);
1754 gfs2_glock_put(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001755 return;
1756 }
1757
1758 case LM_CB_NEED_RECOVERY:
1759 gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data);
1760 if (sdp->sd_recoverd_process)
1761 wake_up_process(sdp->sd_recoverd_process);
1762 return;
1763
1764 case LM_CB_DROPLOCKS:
1765 gfs2_gl_hash_clear(sdp, NO_WAIT);
1766 gfs2_quota_scan(sdp);
1767 return;
1768
1769 default:
1770 gfs2_assert_warn(sdp, 0);
1771 return;
1772 }
1773}
1774
1775/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001776 * demote_ok - Check to see if it's ok to unlock a glock
1777 * @gl: the glock
1778 *
1779 * Returns: 1 if it's ok
1780 */
1781
1782static int demote_ok(struct gfs2_glock *gl)
1783{
1784 struct gfs2_sbd *sdp = gl->gl_sbd;
Steven Whitehouse8fb4b532006-08-30 09:30:00 -04001785 const struct gfs2_glock_operations *glops = gl->gl_ops;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001786 int demote = 1;
1787
1788 if (test_bit(GLF_STICKY, &gl->gl_flags))
1789 demote = 0;
1790 else if (test_bit(GLF_PREFETCH, &gl->gl_flags))
Steven Whitehouse50299962006-09-04 09:49:55 -04001791 demote = time_after_eq(jiffies, gl->gl_stamp +
David Teiglandb3b94fa2006-01-16 16:50:04 +00001792 gfs2_tune_get(sdp, gt_prefetch_secs) * HZ);
1793 else if (glops->go_demote_ok)
1794 demote = glops->go_demote_ok(gl);
1795
1796 return demote;
1797}
1798
1799/**
1800 * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list
1801 * @gl: the glock
1802 *
1803 */
1804
1805void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
1806{
1807 struct gfs2_sbd *sdp = gl->gl_sbd;
1808
1809 spin_lock(&sdp->sd_reclaim_lock);
1810 if (list_empty(&gl->gl_reclaim)) {
1811 gfs2_glock_hold(gl);
1812 list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list);
1813 atomic_inc(&sdp->sd_reclaim_count);
1814 }
1815 spin_unlock(&sdp->sd_reclaim_lock);
1816
1817 wake_up(&sdp->sd_reclaim_wq);
1818}
1819
1820/**
1821 * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list
1822 * @sdp: the filesystem
1823 *
1824 * Called from gfs2_glockd() glock reclaim daemon, or when promoting a
1825 * different glock and we notice that there are a lot of glocks in the
1826 * reclaim list.
1827 *
1828 */
1829
1830void gfs2_reclaim_glock(struct gfs2_sbd *sdp)
1831{
1832 struct gfs2_glock *gl;
1833
1834 spin_lock(&sdp->sd_reclaim_lock);
1835 if (list_empty(&sdp->sd_reclaim_list)) {
1836 spin_unlock(&sdp->sd_reclaim_lock);
1837 return;
1838 }
1839 gl = list_entry(sdp->sd_reclaim_list.next,
1840 struct gfs2_glock, gl_reclaim);
1841 list_del_init(&gl->gl_reclaim);
1842 spin_unlock(&sdp->sd_reclaim_lock);
1843
1844 atomic_dec(&sdp->sd_reclaim_count);
1845 atomic_inc(&sdp->sd_reclaimed);
1846
1847 if (gfs2_glmutex_trylock(gl)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00001848 if (queue_empty(gl, &gl->gl_holders) &&
Steven Whitehouse50299962006-09-04 09:49:55 -04001849 gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001850 handle_callback(gl, LM_ST_UNLOCKED);
1851 gfs2_glmutex_unlock(gl);
1852 }
1853
1854 gfs2_glock_put(gl);
1855}
1856
1857/**
1858 * examine_bucket - Call a function for glock in a hash bucket
1859 * @examiner: the function
1860 * @sdp: the filesystem
1861 * @bucket: the bucket
1862 *
1863 * Returns: 1 if the bucket has entries
1864 */
1865
1866static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp,
Steven Whitehouse37b2fa62006-09-08 13:35:56 -04001867 unsigned int hash)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001868{
Steven Whitehouse24264432006-09-11 21:40:30 -04001869 struct gfs2_glock *gl, *prev = NULL;
1870 int has_entries = 0;
Steven Whitehouseb6397892006-09-12 10:10:01 -04001871 struct hlist_head *head = &gl_hash_table[hash].hb_list;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001872
Steven Whitehouse24264432006-09-11 21:40:30 -04001873 read_lock(gl_lock_addr(hash));
Steven Whitehouseb6397892006-09-12 10:10:01 -04001874 /* Can't use hlist_for_each_entry - don't want prefetch here */
1875 if (hlist_empty(head))
Steven Whitehouse24264432006-09-11 21:40:30 -04001876 goto out;
Steven Whitehouseb6397892006-09-12 10:10:01 -04001877 gl = list_entry(head->first, struct gfs2_glock, gl_list);
1878 while(1) {
Steven Whitehouse24264432006-09-11 21:40:30 -04001879 if (gl->gl_sbd == sdp) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00001880 gfs2_glock_hold(gl);
Steven Whitehouse24264432006-09-11 21:40:30 -04001881 read_unlock(gl_lock_addr(hash));
1882 if (prev)
1883 gfs2_glock_put(prev);
1884 prev = gl;
1885 examiner(gl);
Steven Whitehousea8336342006-09-14 13:57:38 -04001886 has_entries = 1;
Steven Whitehouse24264432006-09-11 21:40:30 -04001887 read_lock(gl_lock_addr(hash));
David Teiglandb3b94fa2006-01-16 16:50:04 +00001888 }
Steven Whitehouseb6397892006-09-12 10:10:01 -04001889 if (gl->gl_list.next == NULL)
1890 break;
Steven Whitehouse24264432006-09-11 21:40:30 -04001891 gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001892 }
Steven Whitehouse24264432006-09-11 21:40:30 -04001893out:
1894 read_unlock(gl_lock_addr(hash));
1895 if (prev)
1896 gfs2_glock_put(prev);
1897 return has_entries;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001898}
1899
1900/**
1901 * scan_glock - look at a glock and see if we can reclaim it
1902 * @gl: the glock to look at
1903 *
1904 */
1905
1906static void scan_glock(struct gfs2_glock *gl)
1907{
Steven Whitehouseb0041572006-11-23 10:51:34 -05001908 if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object)
Steven Whitehouse24264432006-09-11 21:40:30 -04001909 return;
Steven Whitehousea2242db2006-08-24 17:03:05 -04001910
David Teiglandb3b94fa2006-01-16 16:50:04 +00001911 if (gfs2_glmutex_trylock(gl)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00001912 if (queue_empty(gl, &gl->gl_holders) &&
Steven Whitehouse24264432006-09-11 21:40:30 -04001913 gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001914 goto out_schedule;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001915 gfs2_glmutex_unlock(gl);
1916 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001917 return;
1918
Steven Whitehouse627add22006-07-05 13:16:19 -04001919out_schedule:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001920 gfs2_glmutex_unlock(gl);
1921 gfs2_glock_schedule_for_reclaim(gl);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001922}
1923
1924/**
1925 * gfs2_scand_internal - Look for glocks and inodes to toss from memory
1926 * @sdp: the filesystem
1927 *
1928 */
1929
1930void gfs2_scand_internal(struct gfs2_sbd *sdp)
1931{
1932 unsigned int x;
1933
Steven Whitehouse94610612006-09-09 18:59:27 -04001934 for (x = 0; x < GFS2_GL_HASH_SIZE; x++)
Steven Whitehouse37b2fa62006-09-08 13:35:56 -04001935 examine_bucket(scan_glock, sdp, x);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001936}
1937
1938/**
1939 * clear_glock - look at a glock and see if we can free it from glock cache
1940 * @gl: the glock to look at
1941 *
1942 */
1943
1944static void clear_glock(struct gfs2_glock *gl)
1945{
1946 struct gfs2_sbd *sdp = gl->gl_sbd;
1947 int released;
1948
1949 spin_lock(&sdp->sd_reclaim_lock);
1950 if (!list_empty(&gl->gl_reclaim)) {
1951 list_del_init(&gl->gl_reclaim);
1952 atomic_dec(&sdp->sd_reclaim_count);
Steven Whitehouse190562b2006-04-20 16:57:23 -04001953 spin_unlock(&sdp->sd_reclaim_lock);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001954 released = gfs2_glock_put(gl);
1955 gfs2_assert(sdp, !released);
Steven Whitehouse190562b2006-04-20 16:57:23 -04001956 } else {
1957 spin_unlock(&sdp->sd_reclaim_lock);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001958 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001959
1960 if (gfs2_glmutex_trylock(gl)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00001961 if (queue_empty(gl, &gl->gl_holders) &&
1962 gl->gl_state != LM_ST_UNLOCKED)
1963 handle_callback(gl, LM_ST_UNLOCKED);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001964 gfs2_glmutex_unlock(gl);
1965 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001966}
1967
1968/**
1969 * gfs2_gl_hash_clear - Empty out the glock hash table
1970 * @sdp: the filesystem
1971 * @wait: wait until it's all gone
1972 *
1973 * Called when unmounting the filesystem, or when inter-node lock manager
1974 * requests DROPLOCKS because it is running out of capacity.
1975 */
1976
1977void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
1978{
1979 unsigned long t;
1980 unsigned int x;
1981 int cont;
1982
1983 t = jiffies;
1984
1985 for (;;) {
1986 cont = 0;
Steven Whitehouse24264432006-09-11 21:40:30 -04001987 for (x = 0; x < GFS2_GL_HASH_SIZE; x++) {
Steven Whitehouse907b9bc2006-09-25 09:26:04 -04001988 if (examine_bucket(clear_glock, sdp, x))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001989 cont = 1;
Steven Whitehouse24264432006-09-11 21:40:30 -04001990 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00001991
1992 if (!wait || !cont)
1993 break;
1994
1995 if (time_after_eq(jiffies,
1996 t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) {
1997 fs_warn(sdp, "Unmount seems to be stalled. "
1998 "Dumping lock state...\n");
1999 gfs2_dump_lockstate(sdp);
2000 t = jiffies;
2001 }
2002
David Teiglandb3b94fa2006-01-16 16:50:04 +00002003 invalidate_inodes(sdp->sd_vfs);
Steven Whitehousefd88de562006-05-05 16:59:11 -04002004 msleep(10);
David Teiglandb3b94fa2006-01-16 16:50:04 +00002005 }
2006}
2007
2008/*
2009 * Diagnostic routines to help debug distributed deadlock
2010 */
2011
2012/**
2013 * dump_holder - print information about a glock holder
2014 * @str: a string naming the type of holder
2015 * @gh: the glock holder
2016 *
2017 * Returns: 0 on success, -ENOBUFS when we run out of space
2018 */
2019
2020static int dump_holder(char *str, struct gfs2_holder *gh)
2021{
2022 unsigned int x;
2023 int error = -ENOBUFS;
2024
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002025 printk(KERN_INFO " %s\n", str);
2026 printk(KERN_INFO " owner = %ld\n",
David Teiglandb3b94fa2006-01-16 16:50:04 +00002027 (gh->gh_owner) ? (long)gh->gh_owner->pid : -1);
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002028 printk(KERN_INFO " gh_state = %u\n", gh->gh_state);
2029 printk(KERN_INFO " gh_flags =");
David Teiglandb3b94fa2006-01-16 16:50:04 +00002030 for (x = 0; x < 32; x++)
2031 if (gh->gh_flags & (1 << x))
2032 printk(" %u", x);
2033 printk(" \n");
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002034 printk(KERN_INFO " error = %d\n", gh->gh_error);
2035 printk(KERN_INFO " gh_iflags =");
David Teiglandb3b94fa2006-01-16 16:50:04 +00002036 for (x = 0; x < 32; x++)
2037 if (test_bit(x, &gh->gh_iflags))
2038 printk(" %u", x);
2039 printk(" \n");
Steven Whitehoused0dc80d2006-03-29 14:36:49 -05002040 print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip);
David Teiglandb3b94fa2006-01-16 16:50:04 +00002041
2042 error = 0;
2043
2044 return error;
2045}
2046
2047/**
2048 * dump_inode - print information about an inode
2049 * @ip: the inode
2050 *
2051 * Returns: 0 on success, -ENOBUFS when we run out of space
2052 */
2053
2054static int dump_inode(struct gfs2_inode *ip)
2055{
2056 unsigned int x;
2057 int error = -ENOBUFS;
2058
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002059 printk(KERN_INFO " Inode:\n");
2060 printk(KERN_INFO " num = %llu %llu\n",
Steven Whitehouse382066d2006-05-24 10:22:09 -04002061 (unsigned long long)ip->i_num.no_formal_ino,
2062 (unsigned long long)ip->i_num.no_addr);
Steven Whitehouseb60623c2006-11-01 12:22:46 -05002063 printk(KERN_INFO " type = %u\n", IF2DT(ip->i_inode.i_mode));
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002064 printk(KERN_INFO " i_flags =");
David Teiglandb3b94fa2006-01-16 16:50:04 +00002065 for (x = 0; x < 32; x++)
2066 if (test_bit(x, &ip->i_flags))
2067 printk(" %u", x);
2068 printk(" \n");
David Teiglandb3b94fa2006-01-16 16:50:04 +00002069
2070 error = 0;
2071
2072 return error;
2073}
2074
2075/**
2076 * dump_glock - print information about a glock
2077 * @gl: the glock
2078 * @count: where we are in the buffer
2079 *
2080 * Returns: 0 on success, -ENOBUFS when we run out of space
2081 */
2082
2083static int dump_glock(struct gfs2_glock *gl)
2084{
2085 struct gfs2_holder *gh;
2086 unsigned int x;
2087 int error = -ENOBUFS;
2088
2089 spin_lock(&gl->gl_spin);
2090
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002091 printk(KERN_INFO "Glock 0x%p (%u, %llu)\n", gl, gl->gl_name.ln_type,
Steven Whitehouse382066d2006-05-24 10:22:09 -04002092 (unsigned long long)gl->gl_name.ln_number);
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002093 printk(KERN_INFO " gl_flags =");
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002094 for (x = 0; x < 32; x++) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00002095 if (test_bit(x, &gl->gl_flags))
2096 printk(" %u", x);
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002097 }
David Teiglandb3b94fa2006-01-16 16:50:04 +00002098 printk(" \n");
Steven Whitehouse16feb9f2006-09-13 10:43:37 -04002099 printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref));
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002100 printk(KERN_INFO " gl_state = %u\n", gl->gl_state);
Steven Whitehouse320dd102006-05-18 16:25:27 -04002101 printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm);
2102 print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip);
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002103 printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");
2104 printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no");
2105 printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));
2106 printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no");
2107 printk(KERN_INFO " le = %s\n",
David Teiglandb3b94fa2006-01-16 16:50:04 +00002108 (list_empty(&gl->gl_le.le_list)) ? "no" : "yes");
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002109 printk(KERN_INFO " reclaim = %s\n",
David Teiglandb3b94fa2006-01-16 16:50:04 +00002110 (list_empty(&gl->gl_reclaim)) ? "no" : "yes");
2111 if (gl->gl_aspace)
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002112 printk(KERN_INFO " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace,
Russell Cattelan88721872006-08-10 11:08:40 -05002113 gl->gl_aspace->i_mapping->nrpages);
David Teiglandb3b94fa2006-01-16 16:50:04 +00002114 else
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002115 printk(KERN_INFO " aspace = no\n");
2116 printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count));
David Teiglandb3b94fa2006-01-16 16:50:04 +00002117 if (gl->gl_req_gh) {
2118 error = dump_holder("Request", gl->gl_req_gh);
2119 if (error)
2120 goto out;
2121 }
2122 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
2123 error = dump_holder("Holder", gh);
2124 if (error)
2125 goto out;
2126 }
2127 list_for_each_entry(gh, &gl->gl_waiters1, gh_list) {
2128 error = dump_holder("Waiter1", gh);
2129 if (error)
2130 goto out;
2131 }
2132 list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
2133 error = dump_holder("Waiter2", gh);
2134 if (error)
2135 goto out;
2136 }
2137 list_for_each_entry(gh, &gl->gl_waiters3, gh_list) {
2138 error = dump_holder("Waiter3", gh);
2139 if (error)
2140 goto out;
2141 }
Steven Whitehouse5c676f62006-02-27 17:23:27 -05002142 if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00002143 if (!test_bit(GLF_LOCK, &gl->gl_flags) &&
2144 list_empty(&gl->gl_holders)) {
Steven Whitehouse5c676f62006-02-27 17:23:27 -05002145 error = dump_inode(gl->gl_object);
David Teiglandb3b94fa2006-01-16 16:50:04 +00002146 if (error)
2147 goto out;
2148 } else {
2149 error = -ENOBUFS;
Steven Whitehoused92a8d42006-02-27 10:57:14 -05002150 printk(KERN_INFO " Inode: busy\n");
David Teiglandb3b94fa2006-01-16 16:50:04 +00002151 }
2152 }
2153
2154 error = 0;
2155
Steven Whitehousea91ea692006-09-04 12:04:26 -04002156out:
David Teiglandb3b94fa2006-01-16 16:50:04 +00002157 spin_unlock(&gl->gl_spin);
David Teiglandb3b94fa2006-01-16 16:50:04 +00002158 return error;
2159}
2160
2161/**
2162 * gfs2_dump_lockstate - print out the current lockstate
2163 * @sdp: the filesystem
2164 * @ub: the buffer to copy the information into
2165 *
2166 * If @ub is NULL, dump the lockstate to the console.
2167 *
2168 */
2169
Adrian Bunk08bc2db2006-04-28 10:59:12 -04002170static int gfs2_dump_lockstate(struct gfs2_sbd *sdp)
David Teiglandb3b94fa2006-01-16 16:50:04 +00002171{
David Teiglandb3b94fa2006-01-16 16:50:04 +00002172 struct gfs2_glock *gl;
Steven Whitehouseb6397892006-09-12 10:10:01 -04002173 struct hlist_node *h;
David Teiglandb3b94fa2006-01-16 16:50:04 +00002174 unsigned int x;
2175 int error = 0;
2176
2177 for (x = 0; x < GFS2_GL_HASH_SIZE; x++) {
David Teiglandb3b94fa2006-01-16 16:50:04 +00002178
Steven Whitehouse087efdd2006-09-09 16:59:11 -04002179 read_lock(gl_lock_addr(x));
David Teiglandb3b94fa2006-01-16 16:50:04 +00002180
Steven Whitehouseb6397892006-09-12 10:10:01 -04002181 hlist_for_each_entry(gl, h, &gl_hash_table[x].hb_list, gl_list) {
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002182 if (gl->gl_sbd != sdp)
2183 continue;
David Teiglandb3b94fa2006-01-16 16:50:04 +00002184
2185 error = dump_glock(gl);
2186 if (error)
2187 break;
2188 }
2189
Steven Whitehouse087efdd2006-09-09 16:59:11 -04002190 read_unlock(gl_lock_addr(x));
David Teiglandb3b94fa2006-01-16 16:50:04 +00002191
2192 if (error)
2193 break;
2194 }
2195
2196
2197 return error;
2198}
2199
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002200int __init gfs2_glock_init(void)
2201{
2202 unsigned i;
2203 for(i = 0; i < GFS2_GL_HASH_SIZE; i++) {
Steven Whitehouseb6397892006-09-12 10:10:01 -04002204 INIT_HLIST_HEAD(&gl_hash_table[i].hb_list);
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002205 }
Steven Whitehouse087efdd2006-09-09 16:59:11 -04002206#ifdef GL_HASH_LOCK_SZ
2207 for(i = 0; i < GL_HASH_LOCK_SZ; i++) {
2208 rwlock_init(&gl_hash_locks[i]);
2209 }
2210#endif
Steven Whitehouse85d1da62006-09-07 14:40:21 -04002211 return 0;
2212}
2213