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ocfs2: Create the lock status block union.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / ocfs2 / dlmglue.c
CommitLineData
ccd979bd
MF		 1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmglue.c
5 *
6 * Code which implements an OCFS2 specific interface to our DLM.
7 *
8 * Copyright (C) 2003, 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 */
25
26#include <linux/types.h>
27#include <linux/slab.h>
28#include <linux/highmem.h>
29#include <linux/mm.h>
ccd979bd
MF		 30#include <linux/crc32.h>
31#include <linux/kthread.h>
32#include <linux/pagemap.h>
33#include <linux/debugfs.h>
34#include <linux/seq_file.h>
35
36#include <cluster/heartbeat.h>
37#include <cluster/nodemanager.h>
38#include <cluster/tcp.h>
39
ccd979bd
MF		 40#define MLOG_MASK_PREFIX ML_DLM_GLUE
41#include <cluster/masklog.h>
42
43#include "ocfs2.h"
d24fbcda 44#include "ocfs2_lockingver.h"
ccd979bd
MF		 45
46#include "alloc.h"
d680efe9 47#include "dcache.h"
ccd979bd
MF		 48#include "dlmglue.h"
49#include "extent_map.h"
7f1a37e3 50#include "file.h"
ccd979bd
MF		 51#include "heartbeat.h"
52#include "inode.h"
53#include "journal.h"
24ef1815 54#include "stackglue.h"
ccd979bd
MF		 55#include "slot_map.h"
56#include "super.h"
57#include "uptodate.h"
ccd979bd
MF		 58
59#include "buffer_head_io.h"
60
61struct ocfs2_mask_waiter {
62 struct list_head mw_item;
63 int mw_status;
64 struct completion mw_complete;
65 unsigned long mw_mask;
66 unsigned long mw_goal;
67};
68
54a7e755
MF		 69static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres);
70static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres);
cf8e06f1 71static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres);
ccd979bd 72
d680efe9 73/*
cc567d89 74 * Return value from ->downconvert_worker functions.
d680efe9 75 *
b5e500e2 76 * These control the precise actions of ocfs2_unblock_lock()
d680efe9
MF		 77 * and ocfs2_process_blocked_lock()
78 *
79 */
80enum ocfs2_unblock_action {
81 UNBLOCK_CONTINUE = 0, /* Continue downconvert */
82 UNBLOCK_CONTINUE_POST = 1, /* Continue downconvert, fire
83 * ->post_unlock callback */
84 UNBLOCK_STOP_POST = 2, /* Do not downconvert, fire
85 * ->post_unlock() callback. */
86};
87
88struct ocfs2_unblock_ctl {
89 int requeue;
90 enum ocfs2_unblock_action unblock_action;
91};
92
810d5aeb
MF		 93static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
94 int new_level);
95static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres);
96
cc567d89
MF		 97static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
98 int blocking);
99
cc567d89
MF		 100static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
101 int blocking);
d680efe9
MF		 102
103static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
104 struct ocfs2_lock_res *lockres);
ccd979bd 105
6cb129f5
AB		 106
107#define mlog_meta_lvb(__level, __lockres) ocfs2_dump_meta_lvb_info(__level, __PRETTY_FUNCTION__, __LINE__, __lockres)
108
109/* This aids in debugging situations where a bad LVB might be involved. */
110static void ocfs2_dump_meta_lvb_info(u64 level,
111 const char *function,
112 unsigned int line,
113 struct ocfs2_lock_res *lockres)
114{
8f2c9c1b
JB		 115 struct ocfs2_meta_lvb *lvb =
116 (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
6cb129f5
AB		 117
118 mlog(level, "LVB information for %s (called from %s:%u):\n",
119 lockres->l_name, function, line);
120 mlog(level, "version: %u, clusters: %u, generation: 0x%x\n",
121 lvb->lvb_version, be32_to_cpu(lvb->lvb_iclusters),
122 be32_to_cpu(lvb->lvb_igeneration));
123 mlog(level, "size: %llu, uid %u, gid %u, mode 0x%x\n",
124 (unsigned long long)be64_to_cpu(lvb->lvb_isize),
125 be32_to_cpu(lvb->lvb_iuid), be32_to_cpu(lvb->lvb_igid),
126 be16_to_cpu(lvb->lvb_imode));
127 mlog(level, "nlink %u, atime_packed 0x%llx, ctime_packed 0x%llx, "
128 "mtime_packed 0x%llx iattr 0x%x\n", be16_to_cpu(lvb->lvb_inlink),
129 (long long)be64_to_cpu(lvb->lvb_iatime_packed),
130 (long long)be64_to_cpu(lvb->lvb_ictime_packed),
131 (long long)be64_to_cpu(lvb->lvb_imtime_packed),
132 be32_to_cpu(lvb->lvb_iattr));
133}
134
135
f625c979
MF		 136/*
137 * OCFS2 Lock Resource Operations
138 *
139 * These fine tune the behavior of the generic dlmglue locking infrastructure.
0d5dc6c2
MF		 140 *
141 * The most basic of lock types can point ->l_priv to their respective
142 * struct ocfs2_super and allow the default actions to manage things.
143 *
144 * Right now, each lock type also needs to implement an init function,
145 * and trivial lock/unlock wrappers. ocfs2_simple_drop_lockres()
146 * should be called when the lock is no longer needed (i.e., object
147 * destruction time).
f625c979 148 */
ccd979bd 149struct ocfs2_lock_res_ops {
54a7e755
MF		 150 /*
151 * Translate an ocfs2_lock_res * into an ocfs2_super *. Define
152 * this callback if ->l_priv is not an ocfs2_super pointer
153 */
154 struct ocfs2_super * (*get_osb)(struct ocfs2_lock_res *);
b5e500e2 155
0d5dc6c2 156 /*
34d024f8
MF		 157 * Optionally called in the downconvert thread after a
158 * successful downconvert. The lockres will not be referenced
159 * after this callback is called, so it is safe to free
160 * memory, etc.
0d5dc6c2
MF		 161 *
162 * The exact semantics of when this is called are controlled
163 * by ->downconvert_worker()
164 */
d680efe9 165 void (*post_unlock)(struct ocfs2_super *, struct ocfs2_lock_res *);
f625c979 166
16d5b956
MF		 167 /*
168 * Allow a lock type to add checks to determine whether it is
169 * safe to downconvert a lock. Return 0 to re-queue the
170 * downconvert at a later time, nonzero to continue.
171 *
172 * For most locks, the default checks that there are no
173 * incompatible holders are sufficient.
174 *
175 * Called with the lockres spinlock held.
176 */
177 int (*check_downconvert)(struct ocfs2_lock_res *, int);
178
5ef0d4ea
MF		 179 /*
180 * Allows a lock type to populate the lock value block. This
181 * is called on downconvert, and when we drop a lock.
182 *
183 * Locks that want to use this should set LOCK_TYPE_USES_LVB
184 * in the flags field.
185 *
186 * Called with the lockres spinlock held.
187 */
188 void (*set_lvb)(struct ocfs2_lock_res *);
189
cc567d89
MF		 190 /*
191 * Called from the downconvert thread when it is determined
192 * that a lock will be downconverted. This is called without
193 * any locks held so the function can do work that might
194 * schedule (syncing out data, etc).
195 *
196 * This should return any one of the ocfs2_unblock_action
197 * values, depending on what it wants the thread to do.
198 */
199 int (*downconvert_worker)(struct ocfs2_lock_res *, int);
200
f625c979
MF		 201 /*
202 * LOCK_TYPE_* flags which describe the specific requirements
203 * of a lock type. Descriptions of each individual flag follow.
204 */
205 int flags;
ccd979bd
MF		 206};
207
f625c979
MF		 208/*
209 * Some locks want to "refresh" potentially stale data when a
210 * meaningful (PRMODE or EXMODE) lock level is first obtained. If this
211 * flag is set, the OCFS2_LOCK_NEEDS_REFRESH flag will be set on the
212 * individual lockres l_flags member from the ast function. It is
213 * expected that the locking wrapper will clear the
214 * OCFS2_LOCK_NEEDS_REFRESH flag when done.
215 */
216#define LOCK_TYPE_REQUIRES_REFRESH 0x1
217
b80fc012 218/*
5ef0d4ea
MF		 219 * Indicate that a lock type makes use of the lock value block. The
220 * ->set_lvb lock type callback must be defined.
b80fc012
MF		 221 */
222#define LOCK_TYPE_USES_LVB 0x2
223
ccd979bd 224static struct ocfs2_lock_res_ops ocfs2_inode_rw_lops = {
54a7e755 225 .get_osb = ocfs2_get_inode_osb,
f625c979 226 .flags = 0,
ccd979bd
MF		 227};
228
e63aecb6 229static struct ocfs2_lock_res_ops ocfs2_inode_inode_lops = {
54a7e755 230 .get_osb = ocfs2_get_inode_osb,
810d5aeb
MF		 231 .check_downconvert = ocfs2_check_meta_downconvert,
232 .set_lvb = ocfs2_set_meta_lvb,
f1f54068 233 .downconvert_worker = ocfs2_data_convert_worker,
b80fc012 234 .flags = LOCK_TYPE_REQUIRES_REFRESH|LOCK_TYPE_USES_LVB,
ccd979bd
MF		 235};
236
ccd979bd 237static struct ocfs2_lock_res_ops ocfs2_super_lops = {
f625c979 238 .flags = LOCK_TYPE_REQUIRES_REFRESH,
ccd979bd
MF		 239};
240
241static struct ocfs2_lock_res_ops ocfs2_rename_lops = {
f625c979 242 .flags = 0,
ccd979bd
MF		 243};
244
d680efe9 245static struct ocfs2_lock_res_ops ocfs2_dentry_lops = {
54a7e755 246 .get_osb = ocfs2_get_dentry_osb,
d680efe9 247 .post_unlock = ocfs2_dentry_post_unlock,
cc567d89 248 .downconvert_worker = ocfs2_dentry_convert_worker,
f625c979 249 .flags = 0,
d680efe9
MF		 250};
251
50008630
TY		 252static struct ocfs2_lock_res_ops ocfs2_inode_open_lops = {
253 .get_osb = ocfs2_get_inode_osb,
254 .flags = 0,
255};
256
cf8e06f1
MF		 257static struct ocfs2_lock_res_ops ocfs2_flock_lops = {
258 .get_osb = ocfs2_get_file_osb,
259 .flags = 0,
260};
261
d24fbcda
JB		 262/*
263 * This is the filesystem locking protocol version.
264 *
265 * Whenever the filesystem does new things with locks (adds or removes a
266 * lock, orders them differently, does different things underneath a lock),
267 * the version must be changed. The protocol is negotiated when joining
268 * the dlm domain. A node may join the domain if its major version is
269 * identical to all other nodes and its minor version is greater than
270 * or equal to all other nodes. When its minor version is greater than
271 * the other nodes, it will run at the minor version specified by the
272 * other nodes.
273 *
274 * If a locking change is made that will not be compatible with older
275 * versions, the major number must be increased and the minor version set
276 * to zero. If a change merely adds a behavior that can be disabled when
277 * speaking to older versions, the minor version must be increased. If a
278 * change adds a fully backwards compatible change (eg, LVB changes that
279 * are just ignored by older versions), the version does not need to be
280 * updated.
281 */
282const struct dlm_protocol_version ocfs2_locking_protocol = {
283 .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
284 .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
285};
286
ccd979bd
MF		 287static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
288{
289 return lockres->l_type == OCFS2_LOCK_TYPE_META ||
50008630
TY		 290 lockres->l_type == OCFS2_LOCK_TYPE_RW ||
291 lockres->l_type == OCFS2_LOCK_TYPE_OPEN;
ccd979bd
MF		 292}
293
ccd979bd
MF		 294static inline struct inode *ocfs2_lock_res_inode(struct ocfs2_lock_res *lockres)
295{
296 BUG_ON(!ocfs2_is_inode_lock(lockres));
297
298 return (struct inode *) lockres->l_priv;
299}
300
d680efe9
MF		 301static inline struct ocfs2_dentry_lock *ocfs2_lock_res_dl(struct ocfs2_lock_res *lockres)
302{
303 BUG_ON(lockres->l_type != OCFS2_LOCK_TYPE_DENTRY);
304
305 return (struct ocfs2_dentry_lock *)lockres->l_priv;
306}
307
54a7e755
MF		 308static inline struct ocfs2_super *ocfs2_get_lockres_osb(struct ocfs2_lock_res *lockres)
309{
310 if (lockres->l_ops->get_osb)
311 return lockres->l_ops->get_osb(lockres);
312
313 return (struct ocfs2_super *)lockres->l_priv;
314}
315
ccd979bd
MF		 316static int ocfs2_lock_create(struct ocfs2_super *osb,
317 struct ocfs2_lock_res *lockres,
318 int level,
bd3e7610 319 u32 dlm_flags);
ccd979bd
MF		 320static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
321 int wanted);
322static void ocfs2_cluster_unlock(struct ocfs2_super *osb,
323 struct ocfs2_lock_res *lockres,
324 int level);
325static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres);
326static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres);
327static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres);
328static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres, int level);
329static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
330 struct ocfs2_lock_res *lockres);
331static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
332 int convert);
7431cd7e
JB		 333#define ocfs2_log_dlm_error(_func, _err, _lockres) do { \
334 mlog(ML_ERROR, "DLM error %d while calling %s on resource %s\n", \
335 _err, _func, _lockres->l_name); \
ccd979bd 336} while (0)
34d024f8
MF		 337static int ocfs2_downconvert_thread(void *arg);
338static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
339 struct ocfs2_lock_res *lockres);
e63aecb6 340static int ocfs2_inode_lock_update(struct inode *inode,
ccd979bd
MF		 341 struct buffer_head **bh);
342static void ocfs2_drop_osb_locks(struct ocfs2_super *osb);
343static inline int ocfs2_highest_compat_lock_level(int level);
cf8e06f1
MF		 344static void ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
345 int new_level);
346static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
347 struct ocfs2_lock_res *lockres,
348 int new_level,
349 int lvb);
350static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
351 struct ocfs2_lock_res *lockres);
352static int ocfs2_cancel_convert(struct ocfs2_super *osb,
353 struct ocfs2_lock_res *lockres);
354
ccd979bd 355
ccd979bd
MF		 356static void ocfs2_build_lock_name(enum ocfs2_lock_type type,
357 u64 blkno,
358 u32 generation,
359 char *name)
360{
361 int len;
362
363 mlog_entry_void();
364
365 BUG_ON(type >= OCFS2_NUM_LOCK_TYPES);
366
b0697053
MF		 367 len = snprintf(name, OCFS2_LOCK_ID_MAX_LEN, "%c%s%016llx%08x",
368 ocfs2_lock_type_char(type), OCFS2_LOCK_ID_PAD,
369 (long long)blkno, generation);
ccd979bd
MF		 370
371 BUG_ON(len != (OCFS2_LOCK_ID_MAX_LEN - 1));
372
373 mlog(0, "built lock resource with name: %s\n", name);
374
375 mlog_exit_void();
376}
377
34af946a 378static DEFINE_SPINLOCK(ocfs2_dlm_tracking_lock);
ccd979bd
MF		 379
380static void ocfs2_add_lockres_tracking(struct ocfs2_lock_res *res,
381 struct ocfs2_dlm_debug *dlm_debug)
382{
383 mlog(0, "Add tracking for lockres %s\n", res->l_name);
384
385 spin_lock(&ocfs2_dlm_tracking_lock);
386 list_add(&res->l_debug_list, &dlm_debug->d_lockres_tracking);
387 spin_unlock(&ocfs2_dlm_tracking_lock);
388}
389
390static void ocfs2_remove_lockres_tracking(struct ocfs2_lock_res *res)
391{
392 spin_lock(&ocfs2_dlm_tracking_lock);
393 if (!list_empty(&res->l_debug_list))
394 list_del_init(&res->l_debug_list);
395 spin_unlock(&ocfs2_dlm_tracking_lock);
396}
397
398static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
399 struct ocfs2_lock_res *res,
400 enum ocfs2_lock_type type,
ccd979bd
MF		 401 struct ocfs2_lock_res_ops *ops,
402 void *priv)
403{
ccd979bd
MF		 404 res->l_type = type;
405 res->l_ops = ops;
406 res->l_priv = priv;
407
bd3e7610
JB		 408 res->l_level = DLM_LOCK_IV;
409 res->l_requested = DLM_LOCK_IV;
410 res->l_blocking = DLM_LOCK_IV;
ccd979bd
MF		 411 res->l_action = OCFS2_AST_INVALID;
412 res->l_unlock_action = OCFS2_UNLOCK_INVALID;
413
414 res->l_flags = OCFS2_LOCK_INITIALIZED;
415
416 ocfs2_add_lockres_tracking(res, osb->osb_dlm_debug);
417}
418
419void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res)
420{
421 /* This also clears out the lock status block */
422 memset(res, 0, sizeof(struct ocfs2_lock_res));
423 spin_lock_init(&res->l_lock);
424 init_waitqueue_head(&res->l_event);
425 INIT_LIST_HEAD(&res->l_blocked_list);
426 INIT_LIST_HEAD(&res->l_mask_waiters);
427}
428
429void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
430 enum ocfs2_lock_type type,
24c19ef4 431 unsigned int generation,
ccd979bd
MF		 432 struct inode *inode)
433{
434 struct ocfs2_lock_res_ops *ops;
435
436 switch(type) {
437 case OCFS2_LOCK_TYPE_RW:
438 ops = &ocfs2_inode_rw_lops;
439 break;
440 case OCFS2_LOCK_TYPE_META:
e63aecb6 441 ops = &ocfs2_inode_inode_lops;
ccd979bd 442 break;
50008630
TY		 443 case OCFS2_LOCK_TYPE_OPEN:
444 ops = &ocfs2_inode_open_lops;
445 break;
ccd979bd
MF		 446 default:
447 mlog_bug_on_msg(1, "type: %d\n", type);
448 ops = NULL; /* thanks, gcc */
449 break;
450 };
451
d680efe9 452 ocfs2_build_lock_name(type, OCFS2_I(inode)->ip_blkno,
24c19ef4 453 generation, res->l_name);
d680efe9
MF		 454 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), res, type, ops, inode);
455}
456
54a7e755
MF		 457static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres)
458{
459 struct inode *inode = ocfs2_lock_res_inode(lockres);
460
461 return OCFS2_SB(inode->i_sb);
462}
463
cf8e06f1
MF		 464static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres)
465{
466 struct ocfs2_file_private *fp = lockres->l_priv;
467
468 return OCFS2_SB(fp->fp_file->f_mapping->host->i_sb);
469}
470
d680efe9
MF		 471static __u64 ocfs2_get_dentry_lock_ino(struct ocfs2_lock_res *lockres)
472{
473 __be64 inode_blkno_be;
474
475 memcpy(&inode_blkno_be, &lockres->l_name[OCFS2_DENTRY_LOCK_INO_START],
476 sizeof(__be64));
477
478 return be64_to_cpu(inode_blkno_be);
479}
480
54a7e755
MF		 481static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres)
482{
483 struct ocfs2_dentry_lock *dl = lockres->l_priv;
484
485 return OCFS2_SB(dl->dl_inode->i_sb);
486}
487
d680efe9
MF		 488void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
489 u64 parent, struct inode *inode)
490{
491 int len;
492 u64 inode_blkno = OCFS2_I(inode)->ip_blkno;
493 __be64 inode_blkno_be = cpu_to_be64(inode_blkno);
494 struct ocfs2_lock_res *lockres = &dl->dl_lockres;
495
496 ocfs2_lock_res_init_once(lockres);
497
498 /*
499 * Unfortunately, the standard lock naming scheme won't work
500 * here because we have two 16 byte values to use. Instead,
501 * we'll stuff the inode number as a binary value. We still
502 * want error prints to show something without garbling the
503 * display, so drop a null byte in there before the inode
504 * number. A future version of OCFS2 will likely use all
505 * binary lock names. The stringified names have been a
506 * tremendous aid in debugging, but now that the debugfs
507 * interface exists, we can mangle things there if need be.
508 *
509 * NOTE: We also drop the standard "pad" value (the total lock
510 * name size stays the same though - the last part is all
511 * zeros due to the memset in ocfs2_lock_res_init_once()
512 */
513 len = snprintf(lockres->l_name, OCFS2_DENTRY_LOCK_INO_START,
514 "%c%016llx",
515 ocfs2_lock_type_char(OCFS2_LOCK_TYPE_DENTRY),
516 (long long)parent);
517
518 BUG_ON(len != (OCFS2_DENTRY_LOCK_INO_START - 1));
519
520 memcpy(&lockres->l_name[OCFS2_DENTRY_LOCK_INO_START], &inode_blkno_be,
521 sizeof(__be64));
522
523 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
524 OCFS2_LOCK_TYPE_DENTRY, &ocfs2_dentry_lops,
525 dl);
ccd979bd
MF		 526}
527
528static void ocfs2_super_lock_res_init(struct ocfs2_lock_res *res,
529 struct ocfs2_super *osb)
530{
531 /* Superblock lockres doesn't come from a slab so we call init
532 * once on it manually. */
533 ocfs2_lock_res_init_once(res);
d680efe9
MF		 534 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_SUPER, OCFS2_SUPER_BLOCK_BLKNO,
535 0, res->l_name);
ccd979bd 536 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_SUPER,
ccd979bd
MF		 537 &ocfs2_super_lops, osb);
538}
539
540static void ocfs2_rename_lock_res_init(struct ocfs2_lock_res *res,
541 struct ocfs2_super *osb)
542{
543 /* Rename lockres doesn't come from a slab so we call init
544 * once on it manually. */
545 ocfs2_lock_res_init_once(res);
d680efe9
MF		 546 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_RENAME, 0, 0, res->l_name);
547 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_RENAME,
ccd979bd
MF		 548 &ocfs2_rename_lops, osb);
549}
550
cf8e06f1
MF		 551void ocfs2_file_lock_res_init(struct ocfs2_lock_res *lockres,
552 struct ocfs2_file_private *fp)
553{
554 struct inode *inode = fp->fp_file->f_mapping->host;
555 struct ocfs2_inode_info *oi = OCFS2_I(inode);
556
557 ocfs2_lock_res_init_once(lockres);
558 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_FLOCK, oi->ip_blkno,
559 inode->i_generation, lockres->l_name);
560 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
561 OCFS2_LOCK_TYPE_FLOCK, &ocfs2_flock_lops,
562 fp);
563 lockres->l_flags |= OCFS2_LOCK_NOCACHE;
564}
565
ccd979bd
MF		 566void ocfs2_lock_res_free(struct ocfs2_lock_res *res)
567{
568 mlog_entry_void();
569
570 if (!(res->l_flags & OCFS2_LOCK_INITIALIZED))
571 return;
572
573 ocfs2_remove_lockres_tracking(res);
574
575 mlog_bug_on_msg(!list_empty(&res->l_blocked_list),
576 "Lockres %s is on the blocked list\n",
577 res->l_name);
578 mlog_bug_on_msg(!list_empty(&res->l_mask_waiters),
579 "Lockres %s has mask waiters pending\n",
580 res->l_name);
581 mlog_bug_on_msg(spin_is_locked(&res->l_lock),
582 "Lockres %s is locked\n",
583 res->l_name);
584 mlog_bug_on_msg(res->l_ro_holders,
585 "Lockres %s has %u ro holders\n",
586 res->l_name, res->l_ro_holders);
587 mlog_bug_on_msg(res->l_ex_holders,
588 "Lockres %s has %u ex holders\n",
589 res->l_name, res->l_ex_holders);
590
591 /* Need to clear out the lock status block for the dlm */
592 memset(&res->l_lksb, 0, sizeof(res->l_lksb));
593
594 res->l_flags = 0UL;
595 mlog_exit_void();
596}
597
598static inline void ocfs2_inc_holders(struct ocfs2_lock_res *lockres,
599 int level)
600{
601 mlog_entry_void();
602
603 BUG_ON(!lockres);
604
605 switch(level) {
bd3e7610 606 case DLM_LOCK_EX:
ccd979bd
MF		 607 lockres->l_ex_holders++;
608 break;
bd3e7610 609 case DLM_LOCK_PR:
ccd979bd
MF		 610 lockres->l_ro_holders++;
611 break;
612 default:
613 BUG();
614 }
615
616 mlog_exit_void();
617}
618
619static inline void ocfs2_dec_holders(struct ocfs2_lock_res *lockres,
620 int level)
621{
622 mlog_entry_void();
623
624 BUG_ON(!lockres);
625
626 switch(level) {
bd3e7610 627 case DLM_LOCK_EX:
ccd979bd
MF		 628 BUG_ON(!lockres->l_ex_holders);
629 lockres->l_ex_holders--;
630 break;
bd3e7610 631 case DLM_LOCK_PR:
ccd979bd
MF		 632 BUG_ON(!lockres->l_ro_holders);
633 lockres->l_ro_holders--;
634 break;
635 default:
636 BUG();
637 }
638 mlog_exit_void();
639}
640
641/* WARNING: This function lives in a world where the only three lock
642 * levels are EX, PR, and NL. It *will* have to be adjusted when more
643 * lock types are added. */
644static inline int ocfs2_highest_compat_lock_level(int level)
645{
bd3e7610 646 int new_level = DLM_LOCK_EX;
ccd979bd 647
bd3e7610
JB		 648 if (level == DLM_LOCK_EX)
649 new_level = DLM_LOCK_NL;
650 else if (level == DLM_LOCK_PR)
651 new_level = DLM_LOCK_PR;
ccd979bd
MF		 652 return new_level;
653}
654
655static void lockres_set_flags(struct ocfs2_lock_res *lockres,
656 unsigned long newflags)
657{
800deef3 658 struct ocfs2_mask_waiter *mw, *tmp;
ccd979bd
MF		 659
660 assert_spin_locked(&lockres->l_lock);
661
662 lockres->l_flags = newflags;
663
800deef3 664 list_for_each_entry_safe(mw, tmp, &lockres->l_mask_waiters, mw_item) {
ccd979bd
MF		 665 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
666 continue;
667
668 list_del_init(&mw->mw_item);
669 mw->mw_status = 0;
670 complete(&mw->mw_complete);
671 }
672}
673static void lockres_or_flags(struct ocfs2_lock_res *lockres, unsigned long or)
674{
675 lockres_set_flags(lockres, lockres->l_flags | or);
676}
677static void lockres_clear_flags(struct ocfs2_lock_res *lockres,
678 unsigned long clear)
679{
680 lockres_set_flags(lockres, lockres->l_flags & ~clear);
681}
682
683static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres)
684{
685 mlog_entry_void();
686
687 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
688 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
689 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
bd3e7610 690 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
ccd979bd
MF		 691
692 lockres->l_level = lockres->l_requested;
693 if (lockres->l_level <=
694 ocfs2_highest_compat_lock_level(lockres->l_blocking)) {
bd3e7610 695 lockres->l_blocking = DLM_LOCK_NL;
ccd979bd
MF		 696 lockres_clear_flags(lockres, OCFS2_LOCK_BLOCKED);
697 }
698 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
699
700 mlog_exit_void();
701}
702
703static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres)
704{
705 mlog_entry_void();
706
707 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
708 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
709
710 /* Convert from RO to EX doesn't really need anything as our
711 * information is already up to data. Convert from NL to
712 * *anything* however should mark ourselves as needing an
713 * update */
bd3e7610 714 if (lockres->l_level == DLM_LOCK_NL &&
f625c979 715 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
ccd979bd
MF		 716 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
717
718 lockres->l_level = lockres->l_requested;
719 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
720
721 mlog_exit_void();
722}
723
724static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres)
725{
726 mlog_entry_void();
727
3cf0c507 728 BUG_ON((!(lockres->l_flags & OCFS2_LOCK_BUSY)));
ccd979bd
MF		 729 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
730
bd3e7610 731 if (lockres->l_requested > DLM_LOCK_NL &&
f625c979
MF		 732 !(lockres->l_flags & OCFS2_LOCK_LOCAL) &&
733 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
ccd979bd
MF		 734 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
735
736 lockres->l_level = lockres->l_requested;
737 lockres_or_flags(lockres, OCFS2_LOCK_ATTACHED);
738 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
739
740 mlog_exit_void();
741}
742
ccd979bd
MF		 743static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres,
744 int level)
745{
746 int needs_downconvert = 0;
747 mlog_entry_void();
748
749 assert_spin_locked(&lockres->l_lock);
750
751 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
752
753 if (level > lockres->l_blocking) {
754 /* only schedule a downconvert if we haven't already scheduled
755 * one that goes low enough to satisfy the level we're
756 * blocking. this also catches the case where we get
757 * duplicate BASTs */
758 if (ocfs2_highest_compat_lock_level(level) <
759 ocfs2_highest_compat_lock_level(lockres->l_blocking))
760 needs_downconvert = 1;
761
762 lockres->l_blocking = level;
763 }
764
765 mlog_exit(needs_downconvert);
766 return needs_downconvert;
767}
768
aa2623ad 769static void ocfs2_blocking_ast(void *opaque, int level)
ccd979bd 770{
aa2623ad
MF		 771 struct ocfs2_lock_res *lockres = opaque;
772 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
ccd979bd
MF		 773 int needs_downconvert;
774 unsigned long flags;
775
bd3e7610 776 BUG_ON(level <= DLM_LOCK_NL);
ccd979bd 777
aa2623ad
MF		 778 mlog(0, "BAST fired for lockres %s, blocking %d, level %d type %s\n",
779 lockres->l_name, level, lockres->l_level,
780 ocfs2_lock_type_string(lockres->l_type));
781
cf8e06f1
MF		 782 /*
783 * We can skip the bast for locks which don't enable caching -
784 * they'll be dropped at the earliest possible time anyway.
785 */
786 if (lockres->l_flags & OCFS2_LOCK_NOCACHE)
787 return;
788
ccd979bd
MF		 789 spin_lock_irqsave(&lockres->l_lock, flags);
790 needs_downconvert = ocfs2_generic_handle_bast(lockres, level);
791 if (needs_downconvert)
792 ocfs2_schedule_blocked_lock(osb, lockres);
793 spin_unlock_irqrestore(&lockres->l_lock, flags);
794
d680efe9
MF		 795 wake_up(&lockres->l_event);
796
34d024f8 797 ocfs2_wake_downconvert_thread(osb);
ccd979bd
MF		 798}
799
e92d57df 800static void ocfs2_locking_ast(void *opaque)
ccd979bd 801{
e92d57df 802 struct ocfs2_lock_res *lockres = opaque;
ccd979bd
MF		 803 unsigned long flags;
804
805 spin_lock_irqsave(&lockres->l_lock, flags);
806
8f2c9c1b
JB		 807 if (ocfs2_dlm_lock_status(&lockres->l_lksb)) {
808 mlog(ML_ERROR, "lockres %s: lksb status value of %d!\n",
809 lockres->l_name,
810 ocfs2_dlm_lock_status(&lockres->l_lksb));
ccd979bd
MF		 811 spin_unlock_irqrestore(&lockres->l_lock, flags);
812 return;
813 }
814
815 switch(lockres->l_action) {
816 case OCFS2_AST_ATTACH:
817 ocfs2_generic_handle_attach_action(lockres);
e92d57df 818 lockres_clear_flags(lockres, OCFS2_LOCK_LOCAL);
ccd979bd
MF		 819 break;
820 case OCFS2_AST_CONVERT:
821 ocfs2_generic_handle_convert_action(lockres);
822 break;
823 case OCFS2_AST_DOWNCONVERT:
824 ocfs2_generic_handle_downconvert_action(lockres);
825 break;
826 default:
e92d57df
MF		 827 mlog(ML_ERROR, "lockres %s: ast fired with invalid action: %u "
828 "lockres flags = 0x%lx, unlock action: %u\n",
829 lockres->l_name, lockres->l_action, lockres->l_flags,
830 lockres->l_unlock_action);
ccd979bd
MF		 831 BUG();
832 }
833
ccd979bd
MF		 834 /* set it to something invalid so if we get called again we
835 * can catch it. */
836 lockres->l_action = OCFS2_AST_INVALID;
ccd979bd
MF		 837
838 wake_up(&lockres->l_event);
d680efe9 839 spin_unlock_irqrestore(&lockres->l_lock, flags);
ccd979bd
MF		 840}
841
ccd979bd
MF		 842static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
843 int convert)
844{
845 unsigned long flags;
846
847 mlog_entry_void();
848 spin_lock_irqsave(&lockres->l_lock, flags);
849 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
850 if (convert)
851 lockres->l_action = OCFS2_AST_INVALID;
852 else
853 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
854 spin_unlock_irqrestore(&lockres->l_lock, flags);
855
856 wake_up(&lockres->l_event);
857 mlog_exit_void();
858}
859
860/* Note: If we detect another process working on the lock (i.e.,
861 * OCFS2_LOCK_BUSY), we'll bail out returning 0. It's up to the caller
862 * to do the right thing in that case.
863 */
864static int ocfs2_lock_create(struct ocfs2_super *osb,
865 struct ocfs2_lock_res *lockres,
866 int level,
bd3e7610 867 u32 dlm_flags)
ccd979bd
MF		 868{
869 int ret = 0;
ccd979bd
MF		 870 unsigned long flags;
871
872 mlog_entry_void();
873
bd3e7610 874 mlog(0, "lock %s, level = %d, flags = %u\n", lockres->l_name, level,
ccd979bd
MF		 875 dlm_flags);
876
877 spin_lock_irqsave(&lockres->l_lock, flags);
878 if ((lockres->l_flags & OCFS2_LOCK_ATTACHED) ||
879 (lockres->l_flags & OCFS2_LOCK_BUSY)) {
880 spin_unlock_irqrestore(&lockres->l_lock, flags);
881 goto bail;
882 }
883
884 lockres->l_action = OCFS2_AST_ATTACH;
885 lockres->l_requested = level;
886 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
887 spin_unlock_irqrestore(&lockres->l_lock, flags);
888
7431cd7e
JB		 889 ret = ocfs2_dlm_lock(osb->dlm,
890 level,
891 &lockres->l_lksb,
892 dlm_flags,
893 lockres->l_name,
894 OCFS2_LOCK_ID_MAX_LEN - 1,
895 lockres);
896 if (ret) {
897 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
ccd979bd
MF		 898 ocfs2_recover_from_dlm_error(lockres, 1);
899 }
900
7431cd7e 901 mlog(0, "lock %s, return from ocfs2_dlm_lock\n", lockres->l_name);
ccd979bd
MF		 902
903bail:
904 mlog_exit(ret);
905 return ret;
906}
907
908static inline int ocfs2_check_wait_flag(struct ocfs2_lock_res *lockres,
909 int flag)
910{
911 unsigned long flags;
912 int ret;
913
914 spin_lock_irqsave(&lockres->l_lock, flags);
915 ret = lockres->l_flags & flag;
916 spin_unlock_irqrestore(&lockres->l_lock, flags);
917
918 return ret;
919}
920
921static inline void ocfs2_wait_on_busy_lock(struct ocfs2_lock_res *lockres)
922
923{
924 wait_event(lockres->l_event,
925 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_BUSY));
926}
927
928static inline void ocfs2_wait_on_refreshing_lock(struct ocfs2_lock_res *lockres)
929
930{
931 wait_event(lockres->l_event,
932 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_REFRESHING));
933}
934
935/* predict what lock level we'll be dropping down to on behalf
936 * of another node, and return true if the currently wanted
937 * level will be compatible with it. */
938static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
939 int wanted)
940{
941 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
942
943 return wanted <= ocfs2_highest_compat_lock_level(lockres->l_blocking);
944}
945
946static void ocfs2_init_mask_waiter(struct ocfs2_mask_waiter *mw)
947{
948 INIT_LIST_HEAD(&mw->mw_item);
949 init_completion(&mw->mw_complete);
950}
951
952static int ocfs2_wait_for_mask(struct ocfs2_mask_waiter *mw)
953{
954 wait_for_completion(&mw->mw_complete);
955 /* Re-arm the completion in case we want to wait on it again */
956 INIT_COMPLETION(mw->mw_complete);
957 return mw->mw_status;
958}
959
960static void lockres_add_mask_waiter(struct ocfs2_lock_res *lockres,
961 struct ocfs2_mask_waiter *mw,
962 unsigned long mask,
963 unsigned long goal)
964{
965 BUG_ON(!list_empty(&mw->mw_item));
966
967 assert_spin_locked(&lockres->l_lock);
968
969 list_add_tail(&mw->mw_item, &lockres->l_mask_waiters);
970 mw->mw_mask = mask;
971 mw->mw_goal = goal;
972}
973
974/* returns 0 if the mw that was removed was already satisfied, -EBUSY
975 * if the mask still hadn't reached its goal */
976static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
977 struct ocfs2_mask_waiter *mw)
978{
979 unsigned long flags;
980 int ret = 0;
981
982 spin_lock_irqsave(&lockres->l_lock, flags);
983 if (!list_empty(&mw->mw_item)) {
984 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
985 ret = -EBUSY;
986
987 list_del_init(&mw->mw_item);
988 init_completion(&mw->mw_complete);
989 }
990 spin_unlock_irqrestore(&lockres->l_lock, flags);
991
992 return ret;
993
994}
995
cf8e06f1
MF		 996static int ocfs2_wait_for_mask_interruptible(struct ocfs2_mask_waiter *mw,
997 struct ocfs2_lock_res *lockres)
998{
999 int ret;
1000
1001 ret = wait_for_completion_interruptible(&mw->mw_complete);
1002 if (ret)
1003 lockres_remove_mask_waiter(lockres, mw);
1004 else
1005 ret = mw->mw_status;
1006 /* Re-arm the completion in case we want to wait on it again */
1007 INIT_COMPLETION(mw->mw_complete);
1008 return ret;
1009}
1010
ccd979bd
MF		 1011static int ocfs2_cluster_lock(struct ocfs2_super *osb,
1012 struct ocfs2_lock_res *lockres,
1013 int level,
bd3e7610 1014 u32 lkm_flags,
ccd979bd
MF		 1015 int arg_flags)
1016{
1017 struct ocfs2_mask_waiter mw;
ccd979bd
MF		 1018 int wait, catch_signals = !(osb->s_mount_opt & OCFS2_MOUNT_NOINTR);
1019 int ret = 0; /* gcc doesn't realize wait = 1 guarantees ret is set */
1020 unsigned long flags;
1021
1022 mlog_entry_void();
1023
1024 ocfs2_init_mask_waiter(&mw);
1025
b80fc012 1026 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
bd3e7610 1027 lkm_flags |= DLM_LKF_VALBLK;
b80fc012 1028
ccd979bd
MF		 1029again:
1030 wait = 0;
1031
1032 if (catch_signals && signal_pending(current)) {
1033 ret = -ERESTARTSYS;
1034 goto out;
1035 }
1036
1037 spin_lock_irqsave(&lockres->l_lock, flags);
1038
1039 mlog_bug_on_msg(lockres->l_flags & OCFS2_LOCK_FREEING,
1040 "Cluster lock called on freeing lockres %s! flags "
1041 "0x%lx\n", lockres->l_name, lockres->l_flags);
1042
1043 /* We only compare against the currently granted level
1044 * here. If the lock is blocked waiting on a downconvert,
1045 * we'll get caught below. */
1046 if (lockres->l_flags & OCFS2_LOCK_BUSY &&
1047 level > lockres->l_level) {
1048 /* is someone sitting in dlm_lock? If so, wait on
1049 * them. */
1050 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1051 wait = 1;
1052 goto unlock;
1053 }
1054
ccd979bd
MF		 1055 if (lockres->l_flags & OCFS2_LOCK_BLOCKED &&
1056 !ocfs2_may_continue_on_blocked_lock(lockres, level)) {
1057 /* is the lock is currently blocked on behalf of
1058 * another node */
1059 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BLOCKED, 0);
1060 wait = 1;
1061 goto unlock;
1062 }
1063
1064 if (level > lockres->l_level) {
1065 if (lockres->l_action != OCFS2_AST_INVALID)
1066 mlog(ML_ERROR, "lockres %s has action %u pending\n",
1067 lockres->l_name, lockres->l_action);
1068
019d1b22
MF		 1069 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1070 lockres->l_action = OCFS2_AST_ATTACH;
bd3e7610 1071 lkm_flags &= ~DLM_LKF_CONVERT;
019d1b22
MF		 1072 } else {
1073 lockres->l_action = OCFS2_AST_CONVERT;
bd3e7610 1074 lkm_flags |= DLM_LKF_CONVERT;
019d1b22
MF		 1075 }
1076
ccd979bd
MF		 1077 lockres->l_requested = level;
1078 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1079 spin_unlock_irqrestore(&lockres->l_lock, flags);
1080
bd3e7610
JB		 1081 BUG_ON(level == DLM_LOCK_IV);
1082 BUG_ON(level == DLM_LOCK_NL);
ccd979bd
MF		 1083
1084 mlog(0, "lock %s, convert from %d to level = %d\n",
1085 lockres->l_name, lockres->l_level, level);
1086
1087 /* call dlm_lock to upgrade lock now */
7431cd7e
JB		 1088 ret = ocfs2_dlm_lock(osb->dlm,
1089 level,
1090 &lockres->l_lksb,
1091 lkm_flags,
1092 lockres->l_name,
1093 OCFS2_LOCK_ID_MAX_LEN - 1,
1094 lockres);
1095 if (ret) {
1096 if (!(lkm_flags & DLM_LKF_NOQUEUE) ||
1097 (ret != -EAGAIN)) {
24ef1815 1098 ocfs2_log_dlm_error("ocfs2_dlm_lock",
7431cd7e 1099 ret, lockres);
ccd979bd
MF		 1100 }
1101 ocfs2_recover_from_dlm_error(lockres, 1);
1102 goto out;
1103 }
1104
24ef1815 1105 mlog(0, "lock %s, successfull return from ocfs2_dlm_lock\n",
ccd979bd
MF		 1106 lockres->l_name);
1107
1108 /* At this point we've gone inside the dlm and need to
1109 * complete our work regardless. */
1110 catch_signals = 0;
1111
1112 /* wait for busy to clear and carry on */
1113 goto again;
1114 }
1115
1116 /* Ok, if we get here then we're good to go. */
1117 ocfs2_inc_holders(lockres, level);
1118
1119 ret = 0;
1120unlock:
1121 spin_unlock_irqrestore(&lockres->l_lock, flags);
1122out:
1123 /*
1124 * This is helping work around a lock inversion between the page lock
1125 * and dlm locks. One path holds the page lock while calling aops
1126 * which block acquiring dlm locks. The voting thread holds dlm
1127 * locks while acquiring page locks while down converting data locks.
1128 * This block is helping an aop path notice the inversion and back
1129 * off to unlock its page lock before trying the dlm lock again.
1130 */
1131 if (wait && arg_flags & OCFS2_LOCK_NONBLOCK &&
1132 mw.mw_mask & (OCFS2_LOCK_BUSY|OCFS2_LOCK_BLOCKED)) {
1133 wait = 0;
1134 if (lockres_remove_mask_waiter(lockres, &mw))
1135 ret = -EAGAIN;
1136 else
1137 goto again;
1138 }
1139 if (wait) {
1140 ret = ocfs2_wait_for_mask(&mw);
1141 if (ret == 0)
1142 goto again;
1143 mlog_errno(ret);
1144 }
1145
1146 mlog_exit(ret);
1147 return ret;
1148}
1149
1150static void ocfs2_cluster_unlock(struct ocfs2_super *osb,
1151 struct ocfs2_lock_res *lockres,
1152 int level)
1153{
1154 unsigned long flags;
1155
1156 mlog_entry_void();
1157 spin_lock_irqsave(&lockres->l_lock, flags);
1158 ocfs2_dec_holders(lockres, level);
34d024f8 1159 ocfs2_downconvert_on_unlock(osb, lockres);
ccd979bd
MF		 1160 spin_unlock_irqrestore(&lockres->l_lock, flags);
1161 mlog_exit_void();
1162}
1163
da66116e
AB		 1164static int ocfs2_create_new_lock(struct ocfs2_super *osb,
1165 struct ocfs2_lock_res *lockres,
1166 int ex,
1167 int local)
ccd979bd 1168{
bd3e7610 1169 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 1170 unsigned long flags;
bd3e7610 1171 u32 lkm_flags = local ? DLM_LKF_LOCAL : 0;
ccd979bd
MF		 1172
1173 spin_lock_irqsave(&lockres->l_lock, flags);
1174 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
1175 lockres_or_flags(lockres, OCFS2_LOCK_LOCAL);
1176 spin_unlock_irqrestore(&lockres->l_lock, flags);
1177
24c19ef4 1178 return ocfs2_lock_create(osb, lockres, level, lkm_flags);
ccd979bd
MF		 1179}
1180
1181/* Grants us an EX lock on the data and metadata resources, skipping
1182 * the normal cluster directory lookup. Use this ONLY on newly created
1183 * inodes which other nodes can't possibly see, and which haven't been
1184 * hashed in the inode hash yet. This can give us a good performance
1185 * increase as it'll skip the network broadcast normally associated
1186 * with creating a new lock resource. */
1187int ocfs2_create_new_inode_locks(struct inode *inode)
1188{
1189 int ret;
d680efe9 1190 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1191
1192 BUG_ON(!inode);
1193 BUG_ON(!ocfs2_inode_is_new(inode));
1194
1195 mlog_entry_void();
1196
b0697053 1197 mlog(0, "Inode %llu\n", (unsigned long long)OCFS2_I(inode)->ip_blkno);
ccd979bd
MF		 1198
1199 /* NOTE: That we don't increment any of the holder counts, nor
1200 * do we add anything to a journal handle. Since this is
1201 * supposed to be a new inode which the cluster doesn't know
1202 * about yet, there is no need to. As far as the LVB handling
1203 * is concerned, this is basically like acquiring an EX lock
1204 * on a resource which has an invalid one -- we'll set it
1205 * valid when we release the EX. */
1206
24c19ef4 1207 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_rw_lockres, 1, 1);
ccd979bd
MF		 1208 if (ret) {
1209 mlog_errno(ret);
1210 goto bail;
1211 }
1212
24c19ef4 1213 /*
bd3e7610 1214 * We don't want to use DLM_LKF_LOCAL on a meta data lock as they
24c19ef4
MF		 1215 * don't use a generation in their lock names.
1216 */
e63aecb6 1217 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_inode_lockres, 1, 0);
ccd979bd
MF		 1218 if (ret) {
1219 mlog_errno(ret);
1220 goto bail;
1221 }
1222
50008630
TY		 1223 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_open_lockres, 0, 0);
1224 if (ret) {
1225 mlog_errno(ret);
1226 goto bail;
1227 }
1228
ccd979bd
MF		 1229bail:
1230 mlog_exit(ret);
1231 return ret;
1232}
1233
1234int ocfs2_rw_lock(struct inode *inode, int write)
1235{
1236 int status, level;
1237 struct ocfs2_lock_res *lockres;
c271c5c2 1238 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1239
1240 BUG_ON(!inode);
1241
1242 mlog_entry_void();
1243
b0697053
MF		 1244 mlog(0, "inode %llu take %s RW lock\n",
1245 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1246 write ? "EXMODE" : "PRMODE");
1247
c271c5c2
SM		 1248 if (ocfs2_mount_local(osb))
1249 return 0;
1250
ccd979bd
MF		 1251 lockres = &OCFS2_I(inode)->ip_rw_lockres;
1252
bd3e7610 1253 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 1254
1255 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres, level, 0,
1256 0);
1257 if (status < 0)
1258 mlog_errno(status);
1259
1260 mlog_exit(status);
1261 return status;
1262}
1263
1264void ocfs2_rw_unlock(struct inode *inode, int write)
1265{
bd3e7610 1266 int level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 1267 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_rw_lockres;
c271c5c2 1268 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1269
1270 mlog_entry_void();
1271
b0697053
MF		 1272 mlog(0, "inode %llu drop %s RW lock\n",
1273 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1274 write ? "EXMODE" : "PRMODE");
1275
c271c5c2
SM		 1276 if (!ocfs2_mount_local(osb))
1277 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
ccd979bd
MF		 1278
1279 mlog_exit_void();
1280}
1281
50008630
TY		 1282/*
1283 * ocfs2_open_lock always get PR mode lock.
1284 */
1285int ocfs2_open_lock(struct inode *inode)
1286{
1287 int status = 0;
1288 struct ocfs2_lock_res *lockres;
1289 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1290
1291 BUG_ON(!inode);
1292
1293 mlog_entry_void();
1294
1295 mlog(0, "inode %llu take PRMODE open lock\n",
1296 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1297
1298 if (ocfs2_mount_local(osb))
1299 goto out;
1300
1301 lockres = &OCFS2_I(inode)->ip_open_lockres;
1302
1303 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1304 DLM_LOCK_PR, 0, 0);
50008630
TY		 1305 if (status < 0)
1306 mlog_errno(status);
1307
1308out:
1309 mlog_exit(status);
1310 return status;
1311}
1312
1313int ocfs2_try_open_lock(struct inode *inode, int write)
1314{
1315 int status = 0, level;
1316 struct ocfs2_lock_res *lockres;
1317 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1318
1319 BUG_ON(!inode);
1320
1321 mlog_entry_void();
1322
1323 mlog(0, "inode %llu try to take %s open lock\n",
1324 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1325 write ? "EXMODE" : "PRMODE");
1326
1327 if (ocfs2_mount_local(osb))
1328 goto out;
1329
1330 lockres = &OCFS2_I(inode)->ip_open_lockres;
1331
bd3e7610 1332 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
50008630
TY		 1333
1334 /*
1335 * The file system may already holding a PRMODE/EXMODE open lock.
bd3e7610 1336 * Since we pass DLM_LKF_NOQUEUE, the request won't block waiting on
50008630
TY		 1337 * other nodes and the -EAGAIN will indicate to the caller that
1338 * this inode is still in use.
1339 */
1340 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1341 level, DLM_LKF_NOQUEUE, 0);
50008630
TY		 1342
1343out:
1344 mlog_exit(status);
1345 return status;
1346}
1347
1348/*
1349 * ocfs2_open_unlock unlock PR and EX mode open locks.
1350 */
1351void ocfs2_open_unlock(struct inode *inode)
1352{
1353 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_open_lockres;
1354 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1355
1356 mlog_entry_void();
1357
1358 mlog(0, "inode %llu drop open lock\n",
1359 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1360
1361 if (ocfs2_mount_local(osb))
1362 goto out;
1363
1364 if(lockres->l_ro_holders)
1365 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1366 DLM_LOCK_PR);
50008630
TY		 1367 if(lockres->l_ex_holders)
1368 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1369 DLM_LOCK_EX);
50008630
TY		 1370
1371out:
1372 mlog_exit_void();
1373}
1374
cf8e06f1
MF		 1375static int ocfs2_flock_handle_signal(struct ocfs2_lock_res *lockres,
1376 int level)
1377{
1378 int ret;
1379 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
1380 unsigned long flags;
1381 struct ocfs2_mask_waiter mw;
1382
1383 ocfs2_init_mask_waiter(&mw);
1384
1385retry_cancel:
1386 spin_lock_irqsave(&lockres->l_lock, flags);
1387 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
1388 ret = ocfs2_prepare_cancel_convert(osb, lockres);
1389 if (ret) {
1390 spin_unlock_irqrestore(&lockres->l_lock, flags);
1391 ret = ocfs2_cancel_convert(osb, lockres);
1392 if (ret < 0) {
1393 mlog_errno(ret);
1394 goto out;
1395 }
1396 goto retry_cancel;
1397 }
1398 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1399 spin_unlock_irqrestore(&lockres->l_lock, flags);
1400
1401 ocfs2_wait_for_mask(&mw);
1402 goto retry_cancel;
1403 }
1404
1405 ret = -ERESTARTSYS;
1406 /*
1407 * We may still have gotten the lock, in which case there's no
1408 * point to restarting the syscall.
1409 */
1410 if (lockres->l_level == level)
1411 ret = 0;
1412
1413 mlog(0, "Cancel returning %d. flags: 0x%lx, level: %d, act: %d\n", ret,
1414 lockres->l_flags, lockres->l_level, lockres->l_action);
1415
1416 spin_unlock_irqrestore(&lockres->l_lock, flags);
1417
1418out:
1419 return ret;
1420}
1421
1422/*
1423 * ocfs2_file_lock() and ocfs2_file_unlock() map to a single pair of
1424 * flock() calls. The locking approach this requires is sufficiently
1425 * different from all other cluster lock types that we implement a
1426 * seperate path to the "low-level" dlm calls. In particular:
1427 *
1428 * - No optimization of lock levels is done - we take at exactly
1429 * what's been requested.
1430 *
1431 * - No lock caching is employed. We immediately downconvert to
1432 * no-lock at unlock time. This also means flock locks never go on
1433 * the blocking list).
1434 *
1435 * - Since userspace can trivially deadlock itself with flock, we make
1436 * sure to allow cancellation of a misbehaving applications flock()
1437 * request.
1438 *
1439 * - Access to any flock lockres doesn't require concurrency, so we
1440 * can simplify the code by requiring the caller to guarantee
1441 * serialization of dlmglue flock calls.
1442 */
1443int ocfs2_file_lock(struct file *file, int ex, int trylock)
1444{
1445 int ret, level = ex ? LKM_EXMODE : LKM_PRMODE;
1446 unsigned int lkm_flags = trylock ? LKM_NOQUEUE : 0;
1447 unsigned long flags;
1448 struct ocfs2_file_private *fp = file->private_data;
1449 struct ocfs2_lock_res *lockres = &fp->fp_flock;
1450 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
1451 struct ocfs2_mask_waiter mw;
1452
1453 ocfs2_init_mask_waiter(&mw);
1454
1455 if ((lockres->l_flags & OCFS2_LOCK_BUSY) ||
bd3e7610 1456 (lockres->l_level > DLM_LOCK_NL)) {
cf8e06f1
MF		 1457 mlog(ML_ERROR,
1458 "File lock \"%s\" has busy or locked state: flags: 0x%lx, "
1459 "level: %u\n", lockres->l_name, lockres->l_flags,
1460 lockres->l_level);
1461 return -EINVAL;
1462 }
1463
1464 spin_lock_irqsave(&lockres->l_lock, flags);
1465 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1466 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1467 spin_unlock_irqrestore(&lockres->l_lock, flags);
1468
1469 /*
1470 * Get the lock at NLMODE to start - that way we
1471 * can cancel the upconvert request if need be.
1472 */
1473 ret = ocfs2_lock_create(osb, lockres, LKM_NLMODE, 0);
1474 if (ret < 0) {
1475 mlog_errno(ret);
1476 goto out;
1477 }
1478
1479 ret = ocfs2_wait_for_mask(&mw);
1480 if (ret) {
1481 mlog_errno(ret);
1482 goto out;
1483 }
1484 spin_lock_irqsave(&lockres->l_lock, flags);
1485 }
1486
1487 lockres->l_action = OCFS2_AST_CONVERT;
1488 lkm_flags |= LKM_CONVERT;
1489 lockres->l_requested = level;
1490 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1491
1492 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1493 spin_unlock_irqrestore(&lockres->l_lock, flags);
1494
24ef1815
JB		 1495 ret = ocfs2_dlm_lock(osb->dlm, level, &lockres->l_lksb, lkm_flags,
1496 lockres->l_name, OCFS2_LOCK_ID_MAX_LEN - 1,
1497 lockres);
7431cd7e
JB		 1498 if (ret) {
1499 if (!trylock || (ret != -EAGAIN)) {
24ef1815 1500 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
cf8e06f1
MF		 1501 ret = -EINVAL;
1502 }
1503
1504 ocfs2_recover_from_dlm_error(lockres, 1);
1505 lockres_remove_mask_waiter(lockres, &mw);
1506 goto out;
1507 }
1508
1509 ret = ocfs2_wait_for_mask_interruptible(&mw, lockres);
1510 if (ret == -ERESTARTSYS) {
1511 /*
1512 * Userspace can cause deadlock itself with
1513 * flock(). Current behavior locally is to allow the
1514 * deadlock, but abort the system call if a signal is
1515 * received. We follow this example, otherwise a
1516 * poorly written program could sit in kernel until
1517 * reboot.
1518 *
1519 * Handling this is a bit more complicated for Ocfs2
1520 * though. We can't exit this function with an
1521 * outstanding lock request, so a cancel convert is
1522 * required. We intentionally overwrite 'ret' - if the
1523 * cancel fails and the lock was granted, it's easier
1524 * to just bubble sucess back up to the user.
1525 */
1526 ret = ocfs2_flock_handle_signal(lockres, level);
1527 }
1528
1529out:
1530
1531 mlog(0, "Lock: \"%s\" ex: %d, trylock: %d, returns: %d\n",
1532 lockres->l_name, ex, trylock, ret);
1533 return ret;
1534}
1535
1536void ocfs2_file_unlock(struct file *file)
1537{
1538 int ret;
1539 unsigned long flags;
1540 struct ocfs2_file_private *fp = file->private_data;
1541 struct ocfs2_lock_res *lockres = &fp->fp_flock;
1542 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
1543 struct ocfs2_mask_waiter mw;
1544
1545 ocfs2_init_mask_waiter(&mw);
1546
1547 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED))
1548 return;
1549
1550 if (lockres->l_level == LKM_NLMODE)
1551 return;
1552
1553 mlog(0, "Unlock: \"%s\" flags: 0x%lx, level: %d, act: %d\n",
1554 lockres->l_name, lockres->l_flags, lockres->l_level,
1555 lockres->l_action);
1556
1557 spin_lock_irqsave(&lockres->l_lock, flags);
1558 /*
1559 * Fake a blocking ast for the downconvert code.
1560 */
1561 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
bd3e7610 1562 lockres->l_blocking = DLM_LOCK_EX;
cf8e06f1
MF		 1563
1564 ocfs2_prepare_downconvert(lockres, LKM_NLMODE);
1565 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1566 spin_unlock_irqrestore(&lockres->l_lock, flags);
1567
1568 ret = ocfs2_downconvert_lock(osb, lockres, LKM_NLMODE, 0);
1569 if (ret) {
1570 mlog_errno(ret);
1571 return;
1572 }
1573
1574 ret = ocfs2_wait_for_mask(&mw);
1575 if (ret)
1576 mlog_errno(ret);
1577}
1578
34d024f8
MF		 1579static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
1580 struct ocfs2_lock_res *lockres)
ccd979bd
MF		 1581{
1582 int kick = 0;
1583
1584 mlog_entry_void();
1585
1586 /* If we know that another node is waiting on our lock, kick
34d024f8 1587 * the downconvert thread * pre-emptively when we reach a release
ccd979bd
MF		 1588 * condition. */
1589 if (lockres->l_flags & OCFS2_LOCK_BLOCKED) {
1590 switch(lockres->l_blocking) {
bd3e7610 1591 case DLM_LOCK_EX:
ccd979bd
MF		 1592 if (!lockres->l_ex_holders && !lockres->l_ro_holders)
1593 kick = 1;
1594 break;
bd3e7610 1595 case DLM_LOCK_PR:
ccd979bd
MF		 1596 if (!lockres->l_ex_holders)
1597 kick = 1;
1598 break;
1599 default:
1600 BUG();
1601 }
1602 }
1603
1604 if (kick)
34d024f8 1605 ocfs2_wake_downconvert_thread(osb);
ccd979bd
MF		 1606
1607 mlog_exit_void();
1608}
1609
ccd979bd
MF		 1610#define OCFS2_SEC_BITS 34
1611#define OCFS2_SEC_SHIFT (64 - 34)
1612#define OCFS2_NSEC_MASK ((1ULL << OCFS2_SEC_SHIFT) - 1)
1613
1614/* LVB only has room for 64 bits of time here so we pack it for
1615 * now. */
1616static u64 ocfs2_pack_timespec(struct timespec *spec)
1617{
1618 u64 res;
1619 u64 sec = spec->tv_sec;
1620 u32 nsec = spec->tv_nsec;
1621
1622 res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK);
1623
1624 return res;
1625}
1626
1627/* Call this with the lockres locked. I am reasonably sure we don't
1628 * need ip_lock in this function as anyone who would be changing those
e63aecb6 1629 * values is supposed to be blocked in ocfs2_inode_lock right now. */
ccd979bd
MF		 1630static void __ocfs2_stuff_meta_lvb(struct inode *inode)
1631{
1632 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1633 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd
MF		 1634 struct ocfs2_meta_lvb *lvb;
1635
1636 mlog_entry_void();
1637
8f2c9c1b 1638 lvb = (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd 1639
24c19ef4
MF		 1640 /*
1641 * Invalidate the LVB of a deleted inode - this way other
1642 * nodes are forced to go to disk and discover the new inode
1643 * status.
1644 */
1645 if (oi->ip_flags & OCFS2_INODE_DELETED) {
1646 lvb->lvb_version = 0;
1647 goto out;
1648 }
1649
4d3b83f7 1650 lvb->lvb_version = OCFS2_LVB_VERSION;
ccd979bd
MF		 1651 lvb->lvb_isize = cpu_to_be64(i_size_read(inode));
1652 lvb->lvb_iclusters = cpu_to_be32(oi->ip_clusters);
1653 lvb->lvb_iuid = cpu_to_be32(inode->i_uid);
1654 lvb->lvb_igid = cpu_to_be32(inode->i_gid);
1655 lvb->lvb_imode = cpu_to_be16(inode->i_mode);
1656 lvb->lvb_inlink = cpu_to_be16(inode->i_nlink);
1657 lvb->lvb_iatime_packed =
1658 cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime));
1659 lvb->lvb_ictime_packed =
1660 cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime));
1661 lvb->lvb_imtime_packed =
1662 cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime));
ca4d147e 1663 lvb->lvb_iattr = cpu_to_be32(oi->ip_attr);
15b1e36b 1664 lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features);
f9e2d82e 1665 lvb->lvb_igeneration = cpu_to_be32(inode->i_generation);
ccd979bd 1666
24c19ef4 1667out:
ccd979bd
MF		 1668 mlog_meta_lvb(0, lockres);
1669
1670 mlog_exit_void();
1671}
1672
1673static void ocfs2_unpack_timespec(struct timespec *spec,
1674 u64 packed_time)
1675{
1676 spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT;
1677 spec->tv_nsec = packed_time & OCFS2_NSEC_MASK;
1678}
1679
1680static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
1681{
1682 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1683 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd
MF		 1684 struct ocfs2_meta_lvb *lvb;
1685
1686 mlog_entry_void();
1687
1688 mlog_meta_lvb(0, lockres);
1689
8f2c9c1b 1690 lvb = (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd
MF		 1691
1692 /* We're safe here without the lockres lock... */
1693 spin_lock(&oi->ip_lock);
1694 oi->ip_clusters = be32_to_cpu(lvb->lvb_iclusters);
1695 i_size_write(inode, be64_to_cpu(lvb->lvb_isize));
1696
ca4d147e 1697 oi->ip_attr = be32_to_cpu(lvb->lvb_iattr);
15b1e36b 1698 oi->ip_dyn_features = be16_to_cpu(lvb->lvb_idynfeatures);
ca4d147e
HP		 1699 ocfs2_set_inode_flags(inode);
1700
ccd979bd
MF		 1701 /* fast-symlinks are a special case */
1702 if (S_ISLNK(inode->i_mode) && !oi->ip_clusters)
1703 inode->i_blocks = 0;
1704 else
8110b073 1705 inode->i_blocks = ocfs2_inode_sector_count(inode);
ccd979bd
MF		 1706
1707 inode->i_uid = be32_to_cpu(lvb->lvb_iuid);
1708 inode->i_gid = be32_to_cpu(lvb->lvb_igid);
1709 inode->i_mode = be16_to_cpu(lvb->lvb_imode);
1710 inode->i_nlink = be16_to_cpu(lvb->lvb_inlink);
1711 ocfs2_unpack_timespec(&inode->i_atime,
1712 be64_to_cpu(lvb->lvb_iatime_packed));
1713 ocfs2_unpack_timespec(&inode->i_mtime,
1714 be64_to_cpu(lvb->lvb_imtime_packed));
1715 ocfs2_unpack_timespec(&inode->i_ctime,
1716 be64_to_cpu(lvb->lvb_ictime_packed));
1717 spin_unlock(&oi->ip_lock);
1718
1719 mlog_exit_void();
1720}
1721
f9e2d82e
MF		 1722static inline int ocfs2_meta_lvb_is_trustable(struct inode *inode,
1723 struct ocfs2_lock_res *lockres)
ccd979bd 1724{
8f2c9c1b
JB		 1725 struct ocfs2_meta_lvb *lvb =
1726 (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd 1727
f9e2d82e
MF		 1728 if (lvb->lvb_version == OCFS2_LVB_VERSION
1729 && be32_to_cpu(lvb->lvb_igeneration) == inode->i_generation)
ccd979bd
MF		 1730 return 1;
1731 return 0;
1732}
1733
1734/* Determine whether a lock resource needs to be refreshed, and
1735 * arbitrate who gets to refresh it.
1736 *
1737 * 0 means no refresh needed.
1738 *
1739 * > 0 means you need to refresh this and you MUST call
1740 * ocfs2_complete_lock_res_refresh afterwards. */
1741static int ocfs2_should_refresh_lock_res(struct ocfs2_lock_res *lockres)
1742{
1743 unsigned long flags;
1744 int status = 0;
1745
1746 mlog_entry_void();
1747
1748refresh_check:
1749 spin_lock_irqsave(&lockres->l_lock, flags);
1750 if (!(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH)) {
1751 spin_unlock_irqrestore(&lockres->l_lock, flags);
1752 goto bail;
1753 }
1754
1755 if (lockres->l_flags & OCFS2_LOCK_REFRESHING) {
1756 spin_unlock_irqrestore(&lockres->l_lock, flags);
1757
1758 ocfs2_wait_on_refreshing_lock(lockres);
1759 goto refresh_check;
1760 }
1761
1762 /* Ok, I'll be the one to refresh this lock. */
1763 lockres_or_flags(lockres, OCFS2_LOCK_REFRESHING);
1764 spin_unlock_irqrestore(&lockres->l_lock, flags);
1765
1766 status = 1;
1767bail:
1768 mlog_exit(status);
1769 return status;
1770}
1771
1772/* If status is non zero, I'll mark it as not being in refresh
1773 * anymroe, but i won't clear the needs refresh flag. */
1774static inline void ocfs2_complete_lock_res_refresh(struct ocfs2_lock_res *lockres,
1775 int status)
1776{
1777 unsigned long flags;
1778 mlog_entry_void();
1779
1780 spin_lock_irqsave(&lockres->l_lock, flags);
1781 lockres_clear_flags(lockres, OCFS2_LOCK_REFRESHING);
1782 if (!status)
1783 lockres_clear_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
1784 spin_unlock_irqrestore(&lockres->l_lock, flags);
1785
1786 wake_up(&lockres->l_event);
1787
1788 mlog_exit_void();
1789}
1790
1791/* may or may not return a bh if it went to disk. */
e63aecb6 1792static int ocfs2_inode_lock_update(struct inode *inode,
ccd979bd
MF		 1793 struct buffer_head **bh)
1794{
1795 int status = 0;
1796 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1797 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd 1798 struct ocfs2_dinode *fe;
c271c5c2 1799 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1800
1801 mlog_entry_void();
1802
be9e986b
MF		 1803 if (ocfs2_mount_local(osb))
1804 goto bail;
1805
ccd979bd
MF		 1806 spin_lock(&oi->ip_lock);
1807 if (oi->ip_flags & OCFS2_INODE_DELETED) {
b0697053 1808 mlog(0, "Orphaned inode %llu was deleted while we "
ccd979bd 1809 "were waiting on a lock. ip_flags = 0x%x\n",
b0697053 1810 (unsigned long long)oi->ip_blkno, oi->ip_flags);
ccd979bd
MF		 1811 spin_unlock(&oi->ip_lock);
1812 status = -ENOENT;
1813 goto bail;
1814 }
1815 spin_unlock(&oi->ip_lock);
1816
be9e986b
MF		 1817 if (!ocfs2_should_refresh_lock_res(lockres))
1818 goto bail;
ccd979bd
MF		 1819
1820 /* This will discard any caching information we might have had
1821 * for the inode metadata. */
1822 ocfs2_metadata_cache_purge(inode);
1823
83418978
MF		 1824 ocfs2_extent_map_trunc(inode, 0);
1825
be9e986b 1826 if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {
b0697053
MF		 1827 mlog(0, "Trusting LVB on inode %llu\n",
1828 (unsigned long long)oi->ip_blkno);
ccd979bd
MF		 1829 ocfs2_refresh_inode_from_lvb(inode);
1830 } else {
1831 /* Boo, we have to go to disk. */
1832 /* read bh, cast, ocfs2_refresh_inode */
1833 status = ocfs2_read_block(OCFS2_SB(inode->i_sb), oi->ip_blkno,
1834 bh, OCFS2_BH_CACHED, inode);
1835 if (status < 0) {
1836 mlog_errno(status);
1837 goto bail_refresh;
1838 }
1839 fe = (struct ocfs2_dinode *) (*bh)->b_data;
1840
1841 /* This is a good chance to make sure we're not
1842 * locking an invalid object.
1843 *
1844 * We bug on a stale inode here because we checked
1845 * above whether it was wiped from disk. The wiping
1846 * node provides a guarantee that we receive that
1847 * message and can mark the inode before dropping any
1848 * locks associated with it. */
1849 if (!OCFS2_IS_VALID_DINODE(fe)) {
1850 OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
1851 status = -EIO;
1852 goto bail_refresh;
1853 }
1854 mlog_bug_on_msg(inode->i_generation !=
1855 le32_to_cpu(fe->i_generation),
b0697053 1856 "Invalid dinode %llu disk generation: %u "
ccd979bd 1857 "inode->i_generation: %u\n",
b0697053
MF		 1858 (unsigned long long)oi->ip_blkno,
1859 le32_to_cpu(fe->i_generation),
ccd979bd
MF		 1860 inode->i_generation);
1861 mlog_bug_on_msg(le64_to_cpu(fe->i_dtime) ||
1862 !(fe->i_flags & cpu_to_le32(OCFS2_VALID_FL)),
b0697053
MF		 1863 "Stale dinode %llu dtime: %llu flags: 0x%x\n",
1864 (unsigned long long)oi->ip_blkno,
1865 (unsigned long long)le64_to_cpu(fe->i_dtime),
ccd979bd
MF		 1866 le32_to_cpu(fe->i_flags));
1867
1868 ocfs2_refresh_inode(inode, fe);
1869 }
1870
1871 status = 0;
1872bail_refresh:
be9e986b 1873 ocfs2_complete_lock_res_refresh(lockres, status);
ccd979bd
MF		 1874bail:
1875 mlog_exit(status);
1876 return status;
1877}
1878
1879static int ocfs2_assign_bh(struct inode *inode,
1880 struct buffer_head **ret_bh,
1881 struct buffer_head *passed_bh)
1882{
1883 int status;
1884
1885 if (passed_bh) {
1886 /* Ok, the update went to disk for us, use the
1887 * returned bh. */
1888 *ret_bh = passed_bh;
1889 get_bh(*ret_bh);
1890
1891 return 0;
1892 }
1893
1894 status = ocfs2_read_block(OCFS2_SB(inode->i_sb),
1895 OCFS2_I(inode)->ip_blkno,
1896 ret_bh,
1897 OCFS2_BH_CACHED,
1898 inode);
1899 if (status < 0)
1900 mlog_errno(status);
1901
1902 return status;
1903}
1904
1905/*
1906 * returns < 0 error if the callback will never be called, otherwise
1907 * the result of the lock will be communicated via the callback.
1908 */
e63aecb6 1909int ocfs2_inode_lock_full(struct inode *inode,
ccd979bd
MF		 1910 struct buffer_head **ret_bh,
1911 int ex,
1912 int arg_flags)
1913{
bd3e7610
JB		 1914 int status, level, acquired;
1915 u32 dlm_flags;
c271c5c2 1916 struct ocfs2_lock_res *lockres = NULL;
ccd979bd
MF		 1917 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1918 struct buffer_head *local_bh = NULL;
1919
1920 BUG_ON(!inode);
1921
1922 mlog_entry_void();
1923
b0697053
MF		 1924 mlog(0, "inode %llu, take %s META lock\n",
1925 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1926 ex ? "EXMODE" : "PRMODE");
1927
1928 status = 0;
1929 acquired = 0;
1930 /* We'll allow faking a readonly metadata lock for
1931 * rodevices. */
1932 if (ocfs2_is_hard_readonly(osb)) {
1933 if (ex)
1934 status = -EROFS;
1935 goto bail;
1936 }
1937
c271c5c2
SM		 1938 if (ocfs2_mount_local(osb))
1939 goto local;
1940
ccd979bd 1941 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
553abd04 1942 ocfs2_wait_for_recovery(osb);
ccd979bd 1943
e63aecb6 1944 lockres = &OCFS2_I(inode)->ip_inode_lockres;
bd3e7610 1945 level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 1946 dlm_flags = 0;
1947 if (arg_flags & OCFS2_META_LOCK_NOQUEUE)
bd3e7610 1948 dlm_flags |= DLM_LKF_NOQUEUE;
ccd979bd
MF		 1949
1950 status = ocfs2_cluster_lock(osb, lockres, level, dlm_flags, arg_flags);
1951 if (status < 0) {
1952 if (status != -EAGAIN && status != -EIOCBRETRY)
1953 mlog_errno(status);
1954 goto bail;
1955 }
1956
1957 /* Notify the error cleanup path to drop the cluster lock. */
1958 acquired = 1;
1959
1960 /* We wait twice because a node may have died while we were in
1961 * the lower dlm layers. The second time though, we've
1962 * committed to owning this lock so we don't allow signals to
1963 * abort the operation. */
1964 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
553abd04 1965 ocfs2_wait_for_recovery(osb);
ccd979bd 1966
c271c5c2 1967local:
24c19ef4
MF		 1968 /*
1969 * We only see this flag if we're being called from
1970 * ocfs2_read_locked_inode(). It means we're locking an inode
1971 * which hasn't been populated yet, so clear the refresh flag
1972 * and let the caller handle it.
1973 */
1974 if (inode->i_state & I_NEW) {
1975 status = 0;
c271c5c2
SM		 1976 if (lockres)
1977 ocfs2_complete_lock_res_refresh(lockres, 0);
24c19ef4
MF		 1978 goto bail;
1979 }
1980
ccd979bd 1981 /* This is fun. The caller may want a bh back, or it may
e63aecb6 1982 * not. ocfs2_inode_lock_update definitely wants one in, but
ccd979bd
MF		 1983 * may or may not read one, depending on what's in the
1984 * LVB. The result of all of this is that we've *only* gone to
1985 * disk if we have to, so the complexity is worthwhile. */
e63aecb6 1986 status = ocfs2_inode_lock_update(inode, &local_bh);
ccd979bd
MF		 1987 if (status < 0) {
1988 if (status != -ENOENT)
1989 mlog_errno(status);
1990 goto bail;
1991 }
1992
1993 if (ret_bh) {
1994 status = ocfs2_assign_bh(inode, ret_bh, local_bh);
1995 if (status < 0) {
1996 mlog_errno(status);
1997 goto bail;
1998 }
1999 }
2000
ccd979bd
MF		 2001bail:
2002 if (status < 0) {
2003 if (ret_bh && (*ret_bh)) {
2004 brelse(*ret_bh);
2005 *ret_bh = NULL;
2006 }
2007 if (acquired)
e63aecb6 2008 ocfs2_inode_unlock(inode, ex);
ccd979bd
MF		 2009 }
2010
2011 if (local_bh)
2012 brelse(local_bh);
2013
2014 mlog_exit(status);
2015 return status;
2016}
2017
2018/*
34d024f8
MF		 2019 * This is working around a lock inversion between tasks acquiring DLM
2020 * locks while holding a page lock and the downconvert thread which
2021 * blocks dlm lock acquiry while acquiring page locks.
ccd979bd
MF		 2022 *
2023 * ** These _with_page variantes are only intended to be called from aop
2024 * methods that hold page locks and return a very specific *positive* error
2025 * code that aop methods pass up to the VFS -- test for errors with != 0. **
2026 *
34d024f8
MF		 2027 * The DLM is called such that it returns -EAGAIN if it would have
2028 * blocked waiting for the downconvert thread. In that case we unlock
2029 * our page so the downconvert thread can make progress. Once we've
2030 * done this we have to return AOP_TRUNCATED_PAGE so the aop method
2031 * that called us can bubble that back up into the VFS who will then
2032 * immediately retry the aop call.
ccd979bd
MF		 2033 *
2034 * We do a blocking lock and immediate unlock before returning, though, so that
2035 * the lock has a great chance of being cached on this node by the time the VFS
2036 * calls back to retry the aop. This has a potential to livelock as nodes
2037 * ping locks back and forth, but that's a risk we're willing to take to avoid
2038 * the lock inversion simply.
2039 */
e63aecb6 2040int ocfs2_inode_lock_with_page(struct inode *inode,
ccd979bd
MF		 2041 struct buffer_head **ret_bh,
2042 int ex,
2043 struct page *page)
2044{
2045 int ret;
2046
e63aecb6 2047 ret = ocfs2_inode_lock_full(inode, ret_bh, ex, OCFS2_LOCK_NONBLOCK);
ccd979bd
MF		 2048 if (ret == -EAGAIN) {
2049 unlock_page(page);
e63aecb6
MF		 2050 if (ocfs2_inode_lock(inode, ret_bh, ex) == 0)
2051 ocfs2_inode_unlock(inode, ex);
ccd979bd
MF		 2052 ret = AOP_TRUNCATED_PAGE;
2053 }
2054
2055 return ret;
2056}
2057
e63aecb6 2058int ocfs2_inode_lock_atime(struct inode *inode,
7f1a37e3
TY		 2059 struct vfsmount *vfsmnt,
2060 int *level)
2061{
2062 int ret;
2063
2064 mlog_entry_void();
e63aecb6 2065 ret = ocfs2_inode_lock(inode, NULL, 0);
7f1a37e3
TY		 2066 if (ret < 0) {
2067 mlog_errno(ret);
2068 return ret;
2069 }
2070
2071 /*
2072 * If we should update atime, we will get EX lock,
2073 * otherwise we just get PR lock.
2074 */
2075 if (ocfs2_should_update_atime(inode, vfsmnt)) {
2076 struct buffer_head *bh = NULL;
2077
e63aecb6
MF		 2078 ocfs2_inode_unlock(inode, 0);
2079 ret = ocfs2_inode_lock(inode, &bh, 1);
7f1a37e3
TY		 2080 if (ret < 0) {
2081 mlog_errno(ret);
2082 return ret;
2083 }
2084 *level = 1;
2085 if (ocfs2_should_update_atime(inode, vfsmnt))
2086 ocfs2_update_inode_atime(inode, bh);
2087 if (bh)
2088 brelse(bh);
2089 } else
2090 *level = 0;
2091
2092 mlog_exit(ret);
2093 return ret;
2094}
2095
e63aecb6 2096void ocfs2_inode_unlock(struct inode *inode,
ccd979bd
MF		 2097 int ex)
2098{
bd3e7610 2099 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
e63aecb6 2100 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_inode_lockres;
c271c5c2 2101 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 2102
2103 mlog_entry_void();
2104
b0697053
MF		 2105 mlog(0, "inode %llu drop %s META lock\n",
2106 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 2107 ex ? "EXMODE" : "PRMODE");
2108
c271c5c2
SM		 2109 if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)) &&
2110 !ocfs2_mount_local(osb))
ccd979bd
MF		 2111 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
2112
2113 mlog_exit_void();
2114}
2115
2116int ocfs2_super_lock(struct ocfs2_super *osb,
2117 int ex)
2118{
c271c5c2 2119 int status = 0;
bd3e7610 2120 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 2121 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
ccd979bd
MF		 2122
2123 mlog_entry_void();
2124
2125 if (ocfs2_is_hard_readonly(osb))
2126 return -EROFS;
2127
c271c5c2
SM		 2128 if (ocfs2_mount_local(osb))
2129 goto bail;
2130
ccd979bd
MF		 2131 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
2132 if (status < 0) {
2133 mlog_errno(status);
2134 goto bail;
2135 }
2136
2137 /* The super block lock path is really in the best position to
2138 * know when resources covered by the lock need to be
2139 * refreshed, so we do it here. Of course, making sense of
2140 * everything is up to the caller :) */
2141 status = ocfs2_should_refresh_lock_res(lockres);
2142 if (status < 0) {
2143 mlog_errno(status);
2144 goto bail;
2145 }
2146 if (status) {
8e8a4603 2147 status = ocfs2_refresh_slot_info(osb);
ccd979bd
MF		 2148
2149 ocfs2_complete_lock_res_refresh(lockres, status);
2150
2151 if (status < 0)
2152 mlog_errno(status);
2153 }
2154bail:
2155 mlog_exit(status);
2156 return status;
2157}
2158
2159void ocfs2_super_unlock(struct ocfs2_super *osb,
2160 int ex)
2161{
bd3e7610 2162 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 2163 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
2164
c271c5c2
SM		 2165 if (!ocfs2_mount_local(osb))
2166 ocfs2_cluster_unlock(osb, lockres, level);
ccd979bd
MF		 2167}
2168
2169int ocfs2_rename_lock(struct ocfs2_super *osb)
2170{
2171 int status;
2172 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2173
2174 if (ocfs2_is_hard_readonly(osb))
2175 return -EROFS;
2176
c271c5c2
SM		 2177 if (ocfs2_mount_local(osb))
2178 return 0;
2179
bd3e7610 2180 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_EX, 0, 0);
ccd979bd
MF		 2181 if (status < 0)
2182 mlog_errno(status);
2183
2184 return status;
2185}
2186
2187void ocfs2_rename_unlock(struct ocfs2_super *osb)
2188{
2189 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2190
c271c5c2 2191 if (!ocfs2_mount_local(osb))
bd3e7610 2192 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
ccd979bd
MF		 2193}
2194
d680efe9
MF		 2195int ocfs2_dentry_lock(struct dentry *dentry, int ex)
2196{
2197 int ret;
bd3e7610 2198 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
d680efe9
MF		 2199 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2200 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2201
2202 BUG_ON(!dl);
2203
2204 if (ocfs2_is_hard_readonly(osb))
2205 return -EROFS;
2206
c271c5c2
SM		 2207 if (ocfs2_mount_local(osb))
2208 return 0;
2209
d680efe9
MF		 2210 ret = ocfs2_cluster_lock(osb, &dl->dl_lockres, level, 0, 0);
2211 if (ret < 0)
2212 mlog_errno(ret);
2213
2214 return ret;
2215}
2216
2217void ocfs2_dentry_unlock(struct dentry *dentry, int ex)
2218{
bd3e7610 2219 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
d680efe9
MF		 2220 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2221 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2222
c271c5c2
SM		 2223 if (!ocfs2_mount_local(osb))
2224 ocfs2_cluster_unlock(osb, &dl->dl_lockres, level);
d680efe9
MF		 2225}
2226
ccd979bd
MF		 2227/* Reference counting of the dlm debug structure. We want this because
2228 * open references on the debug inodes can live on after a mount, so
2229 * we can't rely on the ocfs2_super to always exist. */
2230static void ocfs2_dlm_debug_free(struct kref *kref)
2231{
2232 struct ocfs2_dlm_debug *dlm_debug;
2233
2234 dlm_debug = container_of(kref, struct ocfs2_dlm_debug, d_refcnt);
2235
2236 kfree(dlm_debug);
2237}
2238
2239void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug)
2240{
2241 if (dlm_debug)
2242 kref_put(&dlm_debug->d_refcnt, ocfs2_dlm_debug_free);
2243}
2244
2245static void ocfs2_get_dlm_debug(struct ocfs2_dlm_debug *debug)
2246{
2247 kref_get(&debug->d_refcnt);
2248}
2249
2250struct ocfs2_dlm_debug *ocfs2_new_dlm_debug(void)
2251{
2252 struct ocfs2_dlm_debug *dlm_debug;
2253
2254 dlm_debug = kmalloc(sizeof(struct ocfs2_dlm_debug), GFP_KERNEL);
2255 if (!dlm_debug) {
2256 mlog_errno(-ENOMEM);
2257 goto out;
2258 }
2259
2260 kref_init(&dlm_debug->d_refcnt);
2261 INIT_LIST_HEAD(&dlm_debug->d_lockres_tracking);
2262 dlm_debug->d_locking_state = NULL;
2263out:
2264 return dlm_debug;
2265}
2266
2267/* Access to this is arbitrated for us via seq_file->sem. */
2268struct ocfs2_dlm_seq_priv {
2269 struct ocfs2_dlm_debug *p_dlm_debug;
2270 struct ocfs2_lock_res p_iter_res;
2271 struct ocfs2_lock_res p_tmp_res;
2272};
2273
2274static struct ocfs2_lock_res *ocfs2_dlm_next_res(struct ocfs2_lock_res *start,
2275 struct ocfs2_dlm_seq_priv *priv)
2276{
2277 struct ocfs2_lock_res *iter, *ret = NULL;
2278 struct ocfs2_dlm_debug *dlm_debug = priv->p_dlm_debug;
2279
2280 assert_spin_locked(&ocfs2_dlm_tracking_lock);
2281
2282 list_for_each_entry(iter, &start->l_debug_list, l_debug_list) {
2283 /* discover the head of the list */
2284 if (&iter->l_debug_list == &dlm_debug->d_lockres_tracking) {
2285 mlog(0, "End of list found, %p\n", ret);
2286 break;
2287 }
2288
2289 /* We track our "dummy" iteration lockres' by a NULL
2290 * l_ops field. */
2291 if (iter->l_ops != NULL) {
2292 ret = iter;
2293 break;
2294 }
2295 }
2296
2297 return ret;
2298}
2299
2300static void *ocfs2_dlm_seq_start(struct seq_file *m, loff_t *pos)
2301{
2302 struct ocfs2_dlm_seq_priv *priv = m->private;
2303 struct ocfs2_lock_res *iter;
2304
2305 spin_lock(&ocfs2_dlm_tracking_lock);
2306 iter = ocfs2_dlm_next_res(&priv->p_iter_res, priv);
2307 if (iter) {
2308 /* Since lockres' have the lifetime of their container
2309 * (which can be inodes, ocfs2_supers, etc) we want to
2310 * copy this out to a temporary lockres while still
2311 * under the spinlock. Obviously after this we can't
2312 * trust any pointers on the copy returned, but that's
2313 * ok as the information we want isn't typically held
2314 * in them. */
2315 priv->p_tmp_res = *iter;
2316 iter = &priv->p_tmp_res;
2317 }
2318 spin_unlock(&ocfs2_dlm_tracking_lock);
2319
2320 return iter;
2321}
2322
2323static void ocfs2_dlm_seq_stop(struct seq_file *m, void *v)
2324{
2325}
2326
2327static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
2328{
2329 struct ocfs2_dlm_seq_priv *priv = m->private;
2330 struct ocfs2_lock_res *iter = v;
2331 struct ocfs2_lock_res *dummy = &priv->p_iter_res;
2332
2333 spin_lock(&ocfs2_dlm_tracking_lock);
2334 iter = ocfs2_dlm_next_res(iter, priv);
2335 list_del_init(&dummy->l_debug_list);
2336 if (iter) {
2337 list_add(&dummy->l_debug_list, &iter->l_debug_list);
2338 priv->p_tmp_res = *iter;
2339 iter = &priv->p_tmp_res;
2340 }
2341 spin_unlock(&ocfs2_dlm_tracking_lock);
2342
2343 return iter;
2344}
2345
2346/* So that debugfs.ocfs2 can determine which format is being used */
2347#define OCFS2_DLM_DEBUG_STR_VERSION 1
2348static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
2349{
2350 int i;
2351 char *lvb;
2352 struct ocfs2_lock_res *lockres = v;
2353
2354 if (!lockres)
2355 return -EINVAL;
2356
d680efe9
MF		 2357 seq_printf(m, "0x%x\t", OCFS2_DLM_DEBUG_STR_VERSION);
2358
2359 if (lockres->l_type == OCFS2_LOCK_TYPE_DENTRY)
2360 seq_printf(m, "%.*s%08x\t", OCFS2_DENTRY_LOCK_INO_START - 1,
2361 lockres->l_name,
2362 (unsigned int)ocfs2_get_dentry_lock_ino(lockres));
2363 else
2364 seq_printf(m, "%.*s\t", OCFS2_LOCK_ID_MAX_LEN, lockres->l_name);
2365
2366 seq_printf(m, "%d\t"
ccd979bd
MF		 2367 "0x%lx\t"
2368 "0x%x\t"
2369 "0x%x\t"
2370 "%u\t"
2371 "%u\t"
2372 "%d\t"
2373 "%d\t",
ccd979bd
MF		 2374 lockres->l_level,
2375 lockres->l_flags,
2376 lockres->l_action,
2377 lockres->l_unlock_action,
2378 lockres->l_ro_holders,
2379 lockres->l_ex_holders,
2380 lockres->l_requested,
2381 lockres->l_blocking);
2382
2383 /* Dump the raw LVB */
8f2c9c1b 2384 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd
MF		 2385 for(i = 0; i < DLM_LVB_LEN; i++)
2386 seq_printf(m, "0x%x\t", lvb[i]);
2387
2388 /* End the line */
2389 seq_printf(m, "\n");
2390 return 0;
2391}
2392
90d99779 2393static const struct seq_operations ocfs2_dlm_seq_ops = {
ccd979bd
MF		 2394 .start = ocfs2_dlm_seq_start,
2395 .stop = ocfs2_dlm_seq_stop,
2396 .next = ocfs2_dlm_seq_next,
2397 .show = ocfs2_dlm_seq_show,
2398};
2399
2400static int ocfs2_dlm_debug_release(struct inode *inode, struct file *file)
2401{
2402 struct seq_file *seq = (struct seq_file *) file->private_data;
2403 struct ocfs2_dlm_seq_priv *priv = seq->private;
2404 struct ocfs2_lock_res *res = &priv->p_iter_res;
2405
2406 ocfs2_remove_lockres_tracking(res);
2407 ocfs2_put_dlm_debug(priv->p_dlm_debug);
2408 return seq_release_private(inode, file);
2409}
2410
2411static int ocfs2_dlm_debug_open(struct inode *inode, struct file *file)
2412{
2413 int ret;
2414 struct ocfs2_dlm_seq_priv *priv;
2415 struct seq_file *seq;
2416 struct ocfs2_super *osb;
2417
2418 priv = kzalloc(sizeof(struct ocfs2_dlm_seq_priv), GFP_KERNEL);
2419 if (!priv) {
2420 ret = -ENOMEM;
2421 mlog_errno(ret);
2422 goto out;
2423 }
8e18e294 2424 osb = inode->i_private;
ccd979bd
MF		 2425 ocfs2_get_dlm_debug(osb->osb_dlm_debug);
2426 priv->p_dlm_debug = osb->osb_dlm_debug;
2427 INIT_LIST_HEAD(&priv->p_iter_res.l_debug_list);
2428
2429 ret = seq_open(file, &ocfs2_dlm_seq_ops);
2430 if (ret) {
2431 kfree(priv);
2432 mlog_errno(ret);
2433 goto out;
2434 }
2435
2436 seq = (struct seq_file *) file->private_data;
2437 seq->private = priv;
2438
2439 ocfs2_add_lockres_tracking(&priv->p_iter_res,
2440 priv->p_dlm_debug);
2441
2442out:
2443 return ret;
2444}
2445
4b6f5d20 2446static const struct file_operations ocfs2_dlm_debug_fops = {
ccd979bd
MF		 2447 .open = ocfs2_dlm_debug_open,
2448 .release = ocfs2_dlm_debug_release,
2449 .read = seq_read,
2450 .llseek = seq_lseek,
2451};
2452
2453static int ocfs2_dlm_init_debug(struct ocfs2_super *osb)
2454{
2455 int ret = 0;
2456 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
2457
2458 dlm_debug->d_locking_state = debugfs_create_file("locking_state",
2459 S_IFREG|S_IRUSR,
2460 osb->osb_debug_root,
2461 osb,
2462 &ocfs2_dlm_debug_fops);
2463 if (!dlm_debug->d_locking_state) {
2464 ret = -EINVAL;
2465 mlog(ML_ERROR,
2466 "Unable to create locking state debugfs file.\n");
2467 goto out;
2468 }
2469
2470 ocfs2_get_dlm_debug(dlm_debug);
2471out:
2472 return ret;
2473}
2474
2475static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)
2476{
2477 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
2478
2479 if (dlm_debug) {
2480 debugfs_remove(dlm_debug->d_locking_state);
2481 ocfs2_put_dlm_debug(dlm_debug);
2482 }
2483}
2484
2485int ocfs2_dlm_init(struct ocfs2_super *osb)
2486{
c271c5c2 2487 int status = 0;
ccd979bd 2488 u32 dlm_key;
c271c5c2 2489 struct dlm_ctxt *dlm = NULL;
ccd979bd
MF		 2490
2491 mlog_entry_void();
2492
c271c5c2
SM		 2493 if (ocfs2_mount_local(osb))
2494 goto local;
2495
ccd979bd
MF		 2496 status = ocfs2_dlm_init_debug(osb);
2497 if (status < 0) {
2498 mlog_errno(status);
2499 goto bail;
2500 }
2501
34d024f8
MF		 2502 /* launch downconvert thread */
2503 osb->dc_task = kthread_run(ocfs2_downconvert_thread, osb, "ocfs2dc");
2504 if (IS_ERR(osb->dc_task)) {
2505 status = PTR_ERR(osb->dc_task);
2506 osb->dc_task = NULL;
ccd979bd
MF		 2507 mlog_errno(status);
2508 goto bail;
2509 }
2510
2511 /* used by the dlm code to make message headers unique, each
2512 * node in this domain must agree on this. */
2513 dlm_key = crc32_le(0, osb->uuid_str, strlen(osb->uuid_str));
2514
2515 /* for now, uuid == domain */
d24fbcda
JB		 2516 dlm = dlm_register_domain(osb->uuid_str, dlm_key,
2517 &osb->osb_locking_proto);
ccd979bd
MF		 2518 if (IS_ERR(dlm)) {
2519 status = PTR_ERR(dlm);
2520 mlog_errno(status);
2521 goto bail;
2522 }
2523
c271c5c2
SM		 2524 dlm_register_eviction_cb(dlm, &osb->osb_eviction_cb);
2525
2526local:
ccd979bd
MF		 2527 ocfs2_super_lock_res_init(&osb->osb_super_lockres, osb);
2528 ocfs2_rename_lock_res_init(&osb->osb_rename_lockres, osb);
2529
ccd979bd
MF		 2530 osb->dlm = dlm;
2531
2532 status = 0;
2533bail:
2534 if (status < 0) {
2535 ocfs2_dlm_shutdown_debug(osb);
34d024f8
MF		 2536 if (osb->dc_task)
2537 kthread_stop(osb->dc_task);
ccd979bd
MF		 2538 }
2539
2540 mlog_exit(status);
2541 return status;
2542}
2543
2544void ocfs2_dlm_shutdown(struct ocfs2_super *osb)
2545{
2546 mlog_entry_void();
2547
2548 dlm_unregister_eviction_cb(&osb->osb_eviction_cb);
2549
2550 ocfs2_drop_osb_locks(osb);
2551
34d024f8
MF		 2552 if (osb->dc_task) {
2553 kthread_stop(osb->dc_task);
2554 osb->dc_task = NULL;
ccd979bd
MF		 2555 }
2556
2557 ocfs2_lock_res_free(&osb->osb_super_lockres);
2558 ocfs2_lock_res_free(&osb->osb_rename_lockres);
2559
2560 dlm_unregister_domain(osb->dlm);
2561 osb->dlm = NULL;
2562
2563 ocfs2_dlm_shutdown_debug(osb);
2564
2565 mlog_exit_void();
2566}
2567
7431cd7e 2568static void ocfs2_unlock_ast(void *opaque, int error)
ccd979bd
MF		 2569{
2570 struct ocfs2_lock_res *lockres = opaque;
2571 unsigned long flags;
2572
2573 mlog_entry_void();
2574
2575 mlog(0, "UNLOCK AST called on lock %s, action = %d\n", lockres->l_name,
2576 lockres->l_unlock_action);
2577
2578 spin_lock_irqsave(&lockres->l_lock, flags);
2579 /* We tried to cancel a convert request, but it was already
2580 * granted. All we want to do here is clear our unlock
2581 * state. The wake_up call done at the bottom is redundant
2582 * (ocfs2_prepare_cancel_convert doesn't sleep on this) but doesn't
2583 * hurt anything anyway */
7431cd7e 2584 if (error == -DLM_ECANCEL &&
ccd979bd
MF		 2585 lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT) {
2586 mlog(0, "Got cancelgrant for %s\n", lockres->l_name);
2587
2588 /* We don't clear the busy flag in this case as it
2589 * should have been cleared by the ast which the dlm
2590 * has called. */
2591 goto complete_unlock;
2592 }
2593
7431cd7e
JB		 2594 /* DLM_EUNLOCK is the success code for unlock */
2595 if (error != -DLM_EUNLOCK) {
2596 mlog(ML_ERROR, "Dlm passes error %d for lock %s, "
2597 "unlock_action %d\n", error, lockres->l_name,
ccd979bd
MF		 2598 lockres->l_unlock_action);
2599 spin_unlock_irqrestore(&lockres->l_lock, flags);
2600 return;
2601 }
2602
2603 switch(lockres->l_unlock_action) {
2604 case OCFS2_UNLOCK_CANCEL_CONVERT:
2605 mlog(0, "Cancel convert success for %s\n", lockres->l_name);
2606 lockres->l_action = OCFS2_AST_INVALID;
2607 break;
2608 case OCFS2_UNLOCK_DROP_LOCK:
bd3e7610 2609 lockres->l_level = DLM_LOCK_IV;
ccd979bd
MF		 2610 break;
2611 default:
2612 BUG();
2613 }
2614
2615 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
2616complete_unlock:
2617 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
2618 spin_unlock_irqrestore(&lockres->l_lock, flags);
2619
2620 wake_up(&lockres->l_event);
2621
2622 mlog_exit_void();
2623}
2624
ccd979bd 2625static int ocfs2_drop_lock(struct ocfs2_super *osb,
0d5dc6c2 2626 struct ocfs2_lock_res *lockres)
ccd979bd 2627{
7431cd7e 2628 int ret;
ccd979bd 2629 unsigned long flags;
bd3e7610 2630 u32 lkm_flags = 0;
ccd979bd
MF		 2631
2632 /* We didn't get anywhere near actually using this lockres. */
2633 if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED))
2634 goto out;
2635
b80fc012 2636 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
bd3e7610 2637 lkm_flags |= DLM_LKF_VALBLK;
b80fc012 2638
ccd979bd
MF		 2639 spin_lock_irqsave(&lockres->l_lock, flags);
2640
2641 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_FREEING),
2642 "lockres %s, flags 0x%lx\n",
2643 lockres->l_name, lockres->l_flags);
2644
2645 while (lockres->l_flags & OCFS2_LOCK_BUSY) {
2646 mlog(0, "waiting on busy lock \"%s\": flags = %lx, action = "
2647 "%u, unlock_action = %u\n",
2648 lockres->l_name, lockres->l_flags, lockres->l_action,
2649 lockres->l_unlock_action);
2650
2651 spin_unlock_irqrestore(&lockres->l_lock, flags);
2652
2653 /* XXX: Today we just wait on any busy
2654 * locks... Perhaps we need to cancel converts in the
2655 * future? */
2656 ocfs2_wait_on_busy_lock(lockres);
2657
2658 spin_lock_irqsave(&lockres->l_lock, flags);
2659 }
2660
0d5dc6c2
MF		 2661 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
2662 if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
bd3e7610 2663 lockres->l_level == DLM_LOCK_EX &&
0d5dc6c2
MF		 2664 !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
2665 lockres->l_ops->set_lvb(lockres);
2666 }
ccd979bd
MF		 2667
2668 if (lockres->l_flags & OCFS2_LOCK_BUSY)
2669 mlog(ML_ERROR, "destroying busy lock: \"%s\"\n",
2670 lockres->l_name);
2671 if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
2672 mlog(0, "destroying blocked lock: \"%s\"\n", lockres->l_name);
2673
2674 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
2675 spin_unlock_irqrestore(&lockres->l_lock, flags);
2676 goto out;
2677 }
2678
2679 lockres_clear_flags(lockres, OCFS2_LOCK_ATTACHED);
2680
2681 /* make sure we never get here while waiting for an ast to
2682 * fire. */
2683 BUG_ON(lockres->l_action != OCFS2_AST_INVALID);
2684
2685 /* is this necessary? */
2686 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
2687 lockres->l_unlock_action = OCFS2_UNLOCK_DROP_LOCK;
2688 spin_unlock_irqrestore(&lockres->l_lock, flags);
2689
2690 mlog(0, "lock %s\n", lockres->l_name);
2691
7431cd7e
JB		 2692 ret = ocfs2_dlm_unlock(osb->dlm, &lockres->l_lksb, lkm_flags,
2693 lockres);
2694 if (ret) {
2695 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
ccd979bd 2696 mlog(ML_ERROR, "lockres flags: %lu\n", lockres->l_flags);
8f2c9c1b
JB		 2697 /* XXX Need to abstract this */
2698 dlm_print_one_lock(lockres->l_lksb.lksb_o2dlm.lockid);
ccd979bd
MF		 2699 BUG();
2700 }
24ef1815 2701 mlog(0, "lock %s, successfull return from ocfs2_dlm_unlock\n",
ccd979bd
MF		 2702 lockres->l_name);
2703
2704 ocfs2_wait_on_busy_lock(lockres);
2705out:
2706 mlog_exit(0);
2707 return 0;
2708}
2709
2710/* Mark the lockres as being dropped. It will no longer be
2711 * queued if blocking, but we still may have to wait on it
34d024f8 2712 * being dequeued from the downconvert thread before we can consider
ccd979bd
MF		 2713 * it safe to drop.
2714 *
2715 * You can *not* attempt to call cluster_lock on this lockres anymore. */
2716void ocfs2_mark_lockres_freeing(struct ocfs2_lock_res *lockres)
2717{
2718 int status;
2719 struct ocfs2_mask_waiter mw;
2720 unsigned long flags;
2721
2722 ocfs2_init_mask_waiter(&mw);
2723
2724 spin_lock_irqsave(&lockres->l_lock, flags);
2725 lockres->l_flags |= OCFS2_LOCK_FREEING;
2726 while (lockres->l_flags & OCFS2_LOCK_QUEUED) {
2727 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_QUEUED, 0);
2728 spin_unlock_irqrestore(&lockres->l_lock, flags);
2729
2730 mlog(0, "Waiting on lockres %s\n", lockres->l_name);
2731
2732 status = ocfs2_wait_for_mask(&mw);
2733 if (status)
2734 mlog_errno(status);
2735
2736 spin_lock_irqsave(&lockres->l_lock, flags);
2737 }
2738 spin_unlock_irqrestore(&lockres->l_lock, flags);
2739}
2740
d680efe9
MF		 2741void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
2742 struct ocfs2_lock_res *lockres)
ccd979bd 2743{
d680efe9 2744 int ret;
ccd979bd 2745
d680efe9 2746 ocfs2_mark_lockres_freeing(lockres);
0d5dc6c2 2747 ret = ocfs2_drop_lock(osb, lockres);
d680efe9
MF		 2748 if (ret)
2749 mlog_errno(ret);
2750}
ccd979bd 2751
d680efe9
MF		 2752static void ocfs2_drop_osb_locks(struct ocfs2_super *osb)
2753{
2754 ocfs2_simple_drop_lockres(osb, &osb->osb_super_lockres);
2755 ocfs2_simple_drop_lockres(osb, &osb->osb_rename_lockres);
ccd979bd
MF		 2756}
2757
ccd979bd
MF		 2758int ocfs2_drop_inode_locks(struct inode *inode)
2759{
2760 int status, err;
ccd979bd
MF		 2761
2762 mlog_entry_void();
2763
2764 /* No need to call ocfs2_mark_lockres_freeing here -
2765 * ocfs2_clear_inode has done it for us. */
2766
2767 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
50008630 2768 &OCFS2_I(inode)->ip_open_lockres);
ccd979bd
MF		 2769 if (err < 0)
2770 mlog_errno(err);
2771
2772 status = err;
2773
2774 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
e63aecb6 2775 &OCFS2_I(inode)->ip_inode_lockres);
ccd979bd
MF		 2776 if (err < 0)
2777 mlog_errno(err);
2778 if (err < 0 && !status)
2779 status = err;
2780
2781 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
0d5dc6c2 2782 &OCFS2_I(inode)->ip_rw_lockres);
ccd979bd
MF		 2783 if (err < 0)
2784 mlog_errno(err);
2785 if (err < 0 && !status)
2786 status = err;
2787
2788 mlog_exit(status);
2789 return status;
2790}
2791
2792static void ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
2793 int new_level)
2794{
2795 assert_spin_locked(&lockres->l_lock);
2796
bd3e7610 2797 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
ccd979bd
MF		 2798
2799 if (lockres->l_level <= new_level) {
bd3e7610 2800 mlog(ML_ERROR, "lockres->l_level (%d) <= new_level (%d)\n",
ccd979bd
MF		 2801 lockres->l_level, new_level);
2802 BUG();
2803 }
2804
2805 mlog(0, "lock %s, new_level = %d, l_blocking = %d\n",
2806 lockres->l_name, new_level, lockres->l_blocking);
2807
2808 lockres->l_action = OCFS2_AST_DOWNCONVERT;
2809 lockres->l_requested = new_level;
2810 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
2811}
2812
2813static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
2814 struct ocfs2_lock_res *lockres,
2815 int new_level,
2816 int lvb)
2817{
bd3e7610
JB		 2818 int ret;
2819 u32 dlm_flags = DLM_LKF_CONVERT;
ccd979bd
MF		 2820
2821 mlog_entry_void();
2822
2823 if (lvb)
bd3e7610 2824 dlm_flags |= DLM_LKF_VALBLK;
ccd979bd 2825
7431cd7e
JB		 2826 ret = ocfs2_dlm_lock(osb->dlm,
2827 new_level,
2828 &lockres->l_lksb,
2829 dlm_flags,
2830 lockres->l_name,
2831 OCFS2_LOCK_ID_MAX_LEN - 1,
2832 lockres);
2833 if (ret) {
2834 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
ccd979bd
MF		 2835 ocfs2_recover_from_dlm_error(lockres, 1);
2836 goto bail;
2837 }
2838
2839 ret = 0;
2840bail:
2841 mlog_exit(ret);
2842 return ret;
2843}
2844
24ef1815 2845/* returns 1 when the caller should unlock and call ocfs2_dlm_unlock */
ccd979bd
MF		 2846static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
2847 struct ocfs2_lock_res *lockres)
2848{
2849 assert_spin_locked(&lockres->l_lock);
2850
2851 mlog_entry_void();
2852 mlog(0, "lock %s\n", lockres->l_name);
2853
2854 if (lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT) {
2855 /* If we're already trying to cancel a lock conversion
2856 * then just drop the spinlock and allow the caller to
2857 * requeue this lock. */
2858
2859 mlog(0, "Lockres %s, skip convert\n", lockres->l_name);
2860 return 0;
2861 }
2862
2863 /* were we in a convert when we got the bast fire? */
2864 BUG_ON(lockres->l_action != OCFS2_AST_CONVERT &&
2865 lockres->l_action != OCFS2_AST_DOWNCONVERT);
2866 /* set things up for the unlockast to know to just
2867 * clear out the ast_action and unset busy, etc. */
2868 lockres->l_unlock_action = OCFS2_UNLOCK_CANCEL_CONVERT;
2869
2870 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_BUSY),
2871 "lock %s, invalid flags: 0x%lx\n",
2872 lockres->l_name, lockres->l_flags);
2873
2874 return 1;
2875}
2876
2877static int ocfs2_cancel_convert(struct ocfs2_super *osb,
2878 struct ocfs2_lock_res *lockres)
2879{
2880 int ret;
ccd979bd
MF		 2881
2882 mlog_entry_void();
2883 mlog(0, "lock %s\n", lockres->l_name);
2884
7431cd7e
JB		 2885 ret = ocfs2_dlm_unlock(osb->dlm, &lockres->l_lksb,
2886 DLM_LKF_CANCEL, lockres);
2887 if (ret) {
2888 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
ccd979bd
MF		 2889 ocfs2_recover_from_dlm_error(lockres, 0);
2890 }
2891
24ef1815 2892 mlog(0, "lock %s return from ocfs2_dlm_unlock\n", lockres->l_name);
ccd979bd 2893
ccd979bd
MF		 2894 mlog_exit(ret);
2895 return ret;
2896}
2897
b5e500e2
MF		 2898static int ocfs2_unblock_lock(struct ocfs2_super *osb,
2899 struct ocfs2_lock_res *lockres,
2900 struct ocfs2_unblock_ctl *ctl)
ccd979bd
MF		 2901{
2902 unsigned long flags;
2903 int blocking;
2904 int new_level;
2905 int ret = 0;
5ef0d4ea 2906 int set_lvb = 0;
ccd979bd
MF		 2907
2908 mlog_entry_void();
2909
2910 spin_lock_irqsave(&lockres->l_lock, flags);
2911
2912 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
2913
2914recheck:
2915 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
d680efe9 2916 ctl->requeue = 1;
ccd979bd
MF		 2917 ret = ocfs2_prepare_cancel_convert(osb, lockres);
2918 spin_unlock_irqrestore(&lockres->l_lock, flags);
2919 if (ret) {
2920 ret = ocfs2_cancel_convert(osb, lockres);
2921 if (ret < 0)
2922 mlog_errno(ret);
2923 }
2924 goto leave;
2925 }
2926
2927 /* if we're blocking an exclusive and we have *any* holders,
2928 * then requeue. */
bd3e7610 2929 if ((lockres->l_blocking == DLM_LOCK_EX)
f7fbfdd1
MF		 2930 && (lockres->l_ex_holders || lockres->l_ro_holders))
2931 goto leave_requeue;
ccd979bd
MF		 2932
2933 /* If it's a PR we're blocking, then only
2934 * requeue if we've got any EX holders */
bd3e7610 2935 if (lockres->l_blocking == DLM_LOCK_PR &&
f7fbfdd1
MF		 2936 lockres->l_ex_holders)
2937 goto leave_requeue;
2938
2939 /*
2940 * Can we get a lock in this state if the holder counts are
2941 * zero? The meta data unblock code used to check this.
2942 */
2943 if ((lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
2944 && (lockres->l_flags & OCFS2_LOCK_REFRESHING))
2945 goto leave_requeue;
ccd979bd 2946
16d5b956
MF		 2947 new_level = ocfs2_highest_compat_lock_level(lockres->l_blocking);
2948
2949 if (lockres->l_ops->check_downconvert
2950 && !lockres->l_ops->check_downconvert(lockres, new_level))
2951 goto leave_requeue;
2952
ccd979bd
MF		 2953 /* If we get here, then we know that there are no more
2954 * incompatible holders (and anyone asking for an incompatible
2955 * lock is blocked). We can now downconvert the lock */
cc567d89 2956 if (!lockres->l_ops->downconvert_worker)
ccd979bd
MF		 2957 goto downconvert;
2958
2959 /* Some lockres types want to do a bit of work before
2960 * downconverting a lock. Allow that here. The worker function
2961 * may sleep, so we save off a copy of what we're blocking as
2962 * it may change while we're not holding the spin lock. */
2963 blocking = lockres->l_blocking;
2964 spin_unlock_irqrestore(&lockres->l_lock, flags);
2965
cc567d89 2966 ctl->unblock_action = lockres->l_ops->downconvert_worker(lockres, blocking);
d680efe9
MF		 2967
2968 if (ctl->unblock_action == UNBLOCK_STOP_POST)
2969 goto leave;
ccd979bd
MF		 2970
2971 spin_lock_irqsave(&lockres->l_lock, flags);
2972 if (blocking != lockres->l_blocking) {
2973 /* If this changed underneath us, then we can't drop
2974 * it just yet. */
2975 goto recheck;
2976 }
2977
2978downconvert:
d680efe9 2979 ctl->requeue = 0;
ccd979bd 2980
5ef0d4ea 2981 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
bd3e7610 2982 if (lockres->l_level == DLM_LOCK_EX)
5ef0d4ea
MF		 2983 set_lvb = 1;
2984
2985 /*
2986 * We only set the lvb if the lock has been fully
2987 * refreshed - otherwise we risk setting stale
2988 * data. Otherwise, there's no need to actually clear
2989 * out the lvb here as it's value is still valid.
2990 */
2991 if (set_lvb && !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
2992 lockres->l_ops->set_lvb(lockres);
2993 }
2994
ccd979bd
MF		 2995 ocfs2_prepare_downconvert(lockres, new_level);
2996 spin_unlock_irqrestore(&lockres->l_lock, flags);
5ef0d4ea 2997 ret = ocfs2_downconvert_lock(osb, lockres, new_level, set_lvb);
ccd979bd
MF		 2998leave:
2999 mlog_exit(ret);
3000 return ret;
f7fbfdd1
MF		 3001
3002leave_requeue:
3003 spin_unlock_irqrestore(&lockres->l_lock, flags);
3004 ctl->requeue = 1;
3005
3006 mlog_exit(0);
3007 return 0;
ccd979bd
MF		 3008}
3009
d680efe9
MF		 3010static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
3011 int blocking)
ccd979bd
MF		 3012{
3013 struct inode *inode;
3014 struct address_space *mapping;
3015
ccd979bd
MF		 3016 inode = ocfs2_lock_res_inode(lockres);
3017 mapping = inode->i_mapping;
3018
1044e401 3019 if (!S_ISREG(inode->i_mode))
f1f54068
MF		 3020 goto out;
3021
7f4a2a97
MF		 3022 /*
3023 * We need this before the filemap_fdatawrite() so that it can
3024 * transfer the dirty bit from the PTE to the
3025 * page. Unfortunately this means that even for EX->PR
3026 * downconverts, we'll lose our mappings and have to build
3027 * them up again.
3028 */
3029 unmap_mapping_range(mapping, 0, 0, 0);
3030
ccd979bd 3031 if (filemap_fdatawrite(mapping)) {
b0697053
MF		 3032 mlog(ML_ERROR, "Could not sync inode %llu for downconvert!",
3033 (unsigned long long)OCFS2_I(inode)->ip_blkno);
ccd979bd
MF		 3034 }
3035 sync_mapping_buffers(mapping);
bd3e7610 3036 if (blocking == DLM_LOCK_EX) {
ccd979bd 3037 truncate_inode_pages(mapping, 0);
ccd979bd
MF		 3038 } else {
3039 /* We only need to wait on the I/O if we're not also
3040 * truncating pages because truncate_inode_pages waits
3041 * for us above. We don't truncate pages if we're
3042 * blocking anything < EXMODE because we want to keep
3043 * them around in that case. */
3044 filemap_fdatawait(mapping);
3045 }
3046
f1f54068 3047out:
d680efe9 3048 return UNBLOCK_CONTINUE;
ccd979bd
MF		 3049}
3050
810d5aeb
MF		 3051static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
3052 int new_level)
3053{
3054 struct inode *inode = ocfs2_lock_res_inode(lockres);
3055 int checkpointed = ocfs2_inode_fully_checkpointed(inode);
3056
bd3e7610
JB		 3057 BUG_ON(new_level != DLM_LOCK_NL && new_level != DLM_LOCK_PR);
3058 BUG_ON(lockres->l_level != DLM_LOCK_EX && !checkpointed);
810d5aeb
MF		 3059
3060 if (checkpointed)
3061 return 1;
3062
3063 ocfs2_start_checkpoint(OCFS2_SB(inode->i_sb));
3064 return 0;
3065}
3066
3067static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres)
3068{
3069 struct inode *inode = ocfs2_lock_res_inode(lockres);
3070
3071 __ocfs2_stuff_meta_lvb(inode);
3072}
3073
d680efe9
MF		 3074/*
3075 * Does the final reference drop on our dentry lock. Right now this
34d024f8 3076 * happens in the downconvert thread, but we could choose to simplify the
d680efe9
MF		 3077 * dlmglue API and push these off to the ocfs2_wq in the future.
3078 */
3079static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
3080 struct ocfs2_lock_res *lockres)
3081{
3082 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
3083 ocfs2_dentry_lock_put(osb, dl);
3084}
3085
3086/*
3087 * d_delete() matching dentries before the lock downconvert.
3088 *
3089 * At this point, any process waiting to destroy the
3090 * dentry_lock due to last ref count is stopped by the
3091 * OCFS2_LOCK_QUEUED flag.
3092 *
3093 * We have two potential problems
3094 *
3095 * 1) If we do the last reference drop on our dentry_lock (via dput)
3096 * we'll wind up in ocfs2_release_dentry_lock(), waiting on
3097 * the downconvert to finish. Instead we take an elevated
3098 * reference and push the drop until after we've completed our
3099 * unblock processing.
3100 *
3101 * 2) There might be another process with a final reference,
3102 * waiting on us to finish processing. If this is the case, we
3103 * detect it and exit out - there's no more dentries anyway.
3104 */
3105static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
3106 int blocking)
3107{
3108 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
3109 struct ocfs2_inode_info *oi = OCFS2_I(dl->dl_inode);
3110 struct dentry *dentry;
3111 unsigned long flags;
3112 int extra_ref = 0;
3113
3114 /*
3115 * This node is blocking another node from getting a read
3116 * lock. This happens when we've renamed within a
3117 * directory. We've forced the other nodes to d_delete(), but
3118 * we never actually dropped our lock because it's still
3119 * valid. The downconvert code will retain a PR for this node,
3120 * so there's no further work to do.
3121 */
bd3e7610 3122 if (blocking == DLM_LOCK_PR)
d680efe9
MF		 3123 return UNBLOCK_CONTINUE;
3124
3125 /*
3126 * Mark this inode as potentially orphaned. The code in
3127 * ocfs2_delete_inode() will figure out whether it actually
3128 * needs to be freed or not.
3129 */
3130 spin_lock(&oi->ip_lock);
3131 oi->ip_flags |= OCFS2_INODE_MAYBE_ORPHANED;
3132 spin_unlock(&oi->ip_lock);
3133
3134 /*
3135 * Yuck. We need to make sure however that the check of
3136 * OCFS2_LOCK_FREEING and the extra reference are atomic with
3137 * respect to a reference decrement or the setting of that
3138 * flag.
3139 */
3140 spin_lock_irqsave(&lockres->l_lock, flags);
3141 spin_lock(&dentry_attach_lock);
3142 if (!(lockres->l_flags & OCFS2_LOCK_FREEING)
3143 && dl->dl_count) {
3144 dl->dl_count++;
3145 extra_ref = 1;
3146 }
3147 spin_unlock(&dentry_attach_lock);
3148 spin_unlock_irqrestore(&lockres->l_lock, flags);
3149
3150 mlog(0, "extra_ref = %d\n", extra_ref);
3151
3152 /*
3153 * We have a process waiting on us in ocfs2_dentry_iput(),
3154 * which means we can't have any more outstanding
3155 * aliases. There's no need to do any more work.
3156 */
3157 if (!extra_ref)
3158 return UNBLOCK_CONTINUE;
3159
3160 spin_lock(&dentry_attach_lock);
3161 while (1) {
3162 dentry = ocfs2_find_local_alias(dl->dl_inode,
3163 dl->dl_parent_blkno, 1);
3164 if (!dentry)
3165 break;
3166 spin_unlock(&dentry_attach_lock);
3167
3168 mlog(0, "d_delete(%.*s);\n", dentry->d_name.len,
3169 dentry->d_name.name);
3170
3171 /*
3172 * The following dcache calls may do an
3173 * iput(). Normally we don't want that from the
3174 * downconverting thread, but in this case it's ok
3175 * because the requesting node already has an
3176 * exclusive lock on the inode, so it can't be queued
3177 * for a downconvert.
3178 */
3179 d_delete(dentry);
3180 dput(dentry);
3181
3182 spin_lock(&dentry_attach_lock);
3183 }
3184 spin_unlock(&dentry_attach_lock);
3185
3186 /*
3187 * If we are the last holder of this dentry lock, there is no
3188 * reason to downconvert so skip straight to the unlock.
3189 */
3190 if (dl->dl_count == 1)
3191 return UNBLOCK_STOP_POST;
3192
3193 return UNBLOCK_CONTINUE_POST;
3194}
3195
24ef1815
JB		 3196static struct ocfs2_locking_protocol lproto = {
3197 .lp_lock_ast = ocfs2_locking_ast,
3198 .lp_blocking_ast = ocfs2_blocking_ast,
3199 .lp_unlock_ast = ocfs2_unlock_ast,
3200};
3201
3202/* This interface isn't the final one, hence the less-than-perfect names */
3203void dlmglue_init_stack(void)
3204{
3205 o2cb_get_stack(&lproto);
3206}
3207
3208void dlmglue_exit_stack(void)
3209{
3210 o2cb_put_stack();
3211}
3212
00600056
AB		 3213static void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
3214 struct ocfs2_lock_res *lockres)
ccd979bd
MF		 3215{
3216 int status;
d680efe9 3217 struct ocfs2_unblock_ctl ctl = {0, 0,};
ccd979bd
MF		 3218 unsigned long flags;
3219
3220 /* Our reference to the lockres in this function can be
3221 * considered valid until we remove the OCFS2_LOCK_QUEUED
3222 * flag. */
3223
3224 mlog_entry_void();
3225
3226 BUG_ON(!lockres);
3227 BUG_ON(!lockres->l_ops);
ccd979bd
MF		 3228
3229 mlog(0, "lockres %s blocked.\n", lockres->l_name);
3230
3231 /* Detect whether a lock has been marked as going away while
34d024f8 3232 * the downconvert thread was processing other things. A lock can
ccd979bd
MF		 3233 * still be marked with OCFS2_LOCK_FREEING after this check,
3234 * but short circuiting here will still save us some
3235 * performance. */
3236 spin_lock_irqsave(&lockres->l_lock, flags);
3237 if (lockres->l_flags & OCFS2_LOCK_FREEING)
3238 goto unqueue;
3239 spin_unlock_irqrestore(&lockres->l_lock, flags);
3240
b5e500e2 3241 status = ocfs2_unblock_lock(osb, lockres, &ctl);
ccd979bd
MF		 3242 if (status < 0)
3243 mlog_errno(status);
3244
3245 spin_lock_irqsave(&lockres->l_lock, flags);
3246unqueue:
d680efe9 3247 if (lockres->l_flags & OCFS2_LOCK_FREEING || !ctl.requeue) {
ccd979bd
MF		 3248 lockres_clear_flags(lockres, OCFS2_LOCK_QUEUED);
3249 } else
3250 ocfs2_schedule_blocked_lock(osb, lockres);
3251
3252 mlog(0, "lockres %s, requeue = %s.\n", lockres->l_name,
d680efe9 3253 ctl.requeue ? "yes" : "no");
ccd979bd
MF		 3254 spin_unlock_irqrestore(&lockres->l_lock, flags);
3255
d680efe9
MF		 3256 if (ctl.unblock_action != UNBLOCK_CONTINUE
3257 && lockres->l_ops->post_unlock)
3258 lockres->l_ops->post_unlock(osb, lockres);
3259
ccd979bd
MF		 3260 mlog_exit_void();
3261}
3262
3263static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
3264 struct ocfs2_lock_res *lockres)
3265{
3266 mlog_entry_void();
3267
3268 assert_spin_locked(&lockres->l_lock);
3269
3270 if (lockres->l_flags & OCFS2_LOCK_FREEING) {
3271 /* Do not schedule a lock for downconvert when it's on
3272 * the way to destruction - any nodes wanting access
3273 * to the resource will get it soon. */
3274 mlog(0, "Lockres %s won't be scheduled: flags 0x%lx\n",
3275 lockres->l_name, lockres->l_flags);
3276 return;
3277 }
3278
3279 lockres_or_flags(lockres, OCFS2_LOCK_QUEUED);
3280
34d024f8 3281 spin_lock(&osb->dc_task_lock);
ccd979bd
MF		 3282 if (list_empty(&lockres->l_blocked_list)) {
3283 list_add_tail(&lockres->l_blocked_list,
3284 &osb->blocked_lock_list);
3285 osb->blocked_lock_count++;
3286 }
34d024f8 3287 spin_unlock(&osb->dc_task_lock);
ccd979bd
MF		 3288
3289 mlog_exit_void();
3290}
34d024f8
MF		 3291
3292static void ocfs2_downconvert_thread_do_work(struct ocfs2_super *osb)
3293{
3294 unsigned long processed;
3295 struct ocfs2_lock_res *lockres;
3296
3297 mlog_entry_void();
3298
3299 spin_lock(&osb->dc_task_lock);
3300 /* grab this early so we know to try again if a state change and
3301 * wake happens part-way through our work */
3302 osb->dc_work_sequence = osb->dc_wake_sequence;
3303
3304 processed = osb->blocked_lock_count;
3305 while (processed) {
3306 BUG_ON(list_empty(&osb->blocked_lock_list));
3307
3308 lockres = list_entry(osb->blocked_lock_list.next,
3309 struct ocfs2_lock_res, l_blocked_list);
3310 list_del_init(&lockres->l_blocked_list);
3311 osb->blocked_lock_count--;
3312 spin_unlock(&osb->dc_task_lock);
3313
3314 BUG_ON(!processed);
3315 processed--;
3316
3317 ocfs2_process_blocked_lock(osb, lockres);
3318
3319 spin_lock(&osb->dc_task_lock);
3320 }
3321 spin_unlock(&osb->dc_task_lock);
3322
3323 mlog_exit_void();
3324}
3325
3326static int ocfs2_downconvert_thread_lists_empty(struct ocfs2_super *osb)
3327{
3328 int empty = 0;
3329
3330 spin_lock(&osb->dc_task_lock);
3331 if (list_empty(&osb->blocked_lock_list))
3332 empty = 1;
3333
3334 spin_unlock(&osb->dc_task_lock);
3335 return empty;
3336}
3337
3338static int ocfs2_downconvert_thread_should_wake(struct ocfs2_super *osb)
3339{
3340 int should_wake = 0;
3341
3342 spin_lock(&osb->dc_task_lock);
3343 if (osb->dc_work_sequence != osb->dc_wake_sequence)
3344 should_wake = 1;
3345 spin_unlock(&osb->dc_task_lock);
3346
3347 return should_wake;
3348}
3349
200bfae3 3350static int ocfs2_downconvert_thread(void *arg)
34d024f8
MF		 3351{
3352 int status = 0;
3353 struct ocfs2_super *osb = arg;
3354
3355 /* only quit once we've been asked to stop and there is no more
3356 * work available */
3357 while (!(kthread_should_stop() &&
3358 ocfs2_downconvert_thread_lists_empty(osb))) {
3359
3360 wait_event_interruptible(osb->dc_event,
3361 ocfs2_downconvert_thread_should_wake(osb) ||
3362 kthread_should_stop());
3363
3364 mlog(0, "downconvert_thread: awoken\n");
3365
3366 ocfs2_downconvert_thread_do_work(osb);
3367 }
3368
3369 osb->dc_task = NULL;
3370 return status;
3371}
3372
3373void ocfs2_wake_downconvert_thread(struct ocfs2_super *osb)
3374{
3375 spin_lock(&osb->dc_task_lock);
3376 /* make sure the voting thread gets a swipe at whatever changes
3377 * the caller may have made to the voting state */
3378 osb->dc_wake_sequence++;
3379 spin_unlock(&osb->dc_task_lock);
3380 wake_up(&osb->dc_event);
3381}
kernel source for telekom puls (alcatel/mediatek)