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ocfs2: Move o2hb functionality into the stack glue.
[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/kthread.h>
31#include <linux/pagemap.h>
32#include <linux/debugfs.h>
33#include <linux/seq_file.h>
34
ccd979bd
MF		 35#define MLOG_MASK_PREFIX ML_DLM_GLUE
36#include <cluster/masklog.h>
37
38#include "ocfs2.h"
d24fbcda 39#include "ocfs2_lockingver.h"
ccd979bd
MF		 40
41#include "alloc.h"
d680efe9 42#include "dcache.h"
ccd979bd
MF		 43#include "dlmglue.h"
44#include "extent_map.h"
7f1a37e3 45#include "file.h"
ccd979bd
MF		 46#include "heartbeat.h"
47#include "inode.h"
48#include "journal.h"
24ef1815 49#include "stackglue.h"
ccd979bd
MF		 50#include "slot_map.h"
51#include "super.h"
52#include "uptodate.h"
ccd979bd
MF		 53
54#include "buffer_head_io.h"
55
56struct ocfs2_mask_waiter {
57 struct list_head mw_item;
58 int mw_status;
59 struct completion mw_complete;
60 unsigned long mw_mask;
61 unsigned long mw_goal;
62};
63
54a7e755
MF		 64static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres);
65static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres);
cf8e06f1 66static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres);
ccd979bd 67
d680efe9 68/*
cc567d89 69 * Return value from ->downconvert_worker functions.
d680efe9 70 *
b5e500e2 71 * These control the precise actions of ocfs2_unblock_lock()
d680efe9
MF		 72 * and ocfs2_process_blocked_lock()
73 *
74 */
75enum ocfs2_unblock_action {
76 UNBLOCK_CONTINUE = 0, /* Continue downconvert */
77 UNBLOCK_CONTINUE_POST = 1, /* Continue downconvert, fire
78 * ->post_unlock callback */
79 UNBLOCK_STOP_POST = 2, /* Do not downconvert, fire
80 * ->post_unlock() callback. */
81};
82
83struct ocfs2_unblock_ctl {
84 int requeue;
85 enum ocfs2_unblock_action unblock_action;
86};
87
810d5aeb
MF		 88static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
89 int new_level);
90static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres);
91
cc567d89
MF		 92static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
93 int blocking);
94
cc567d89
MF		 95static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
96 int blocking);
d680efe9
MF		 97
98static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
99 struct ocfs2_lock_res *lockres);
ccd979bd 100
6cb129f5
AB		 101
102#define mlog_meta_lvb(__level, __lockres) ocfs2_dump_meta_lvb_info(__level, __PRETTY_FUNCTION__, __LINE__, __lockres)
103
104/* This aids in debugging situations where a bad LVB might be involved. */
105static void ocfs2_dump_meta_lvb_info(u64 level,
106 const char *function,
107 unsigned int line,
108 struct ocfs2_lock_res *lockres)
109{
8f2c9c1b
JB		 110 struct ocfs2_meta_lvb *lvb =
111 (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
6cb129f5
AB		 112
113 mlog(level, "LVB information for %s (called from %s:%u):\n",
114 lockres->l_name, function, line);
115 mlog(level, "version: %u, clusters: %u, generation: 0x%x\n",
116 lvb->lvb_version, be32_to_cpu(lvb->lvb_iclusters),
117 be32_to_cpu(lvb->lvb_igeneration));
118 mlog(level, "size: %llu, uid %u, gid %u, mode 0x%x\n",
119 (unsigned long long)be64_to_cpu(lvb->lvb_isize),
120 be32_to_cpu(lvb->lvb_iuid), be32_to_cpu(lvb->lvb_igid),
121 be16_to_cpu(lvb->lvb_imode));
122 mlog(level, "nlink %u, atime_packed 0x%llx, ctime_packed 0x%llx, "
123 "mtime_packed 0x%llx iattr 0x%x\n", be16_to_cpu(lvb->lvb_inlink),
124 (long long)be64_to_cpu(lvb->lvb_iatime_packed),
125 (long long)be64_to_cpu(lvb->lvb_ictime_packed),
126 (long long)be64_to_cpu(lvb->lvb_imtime_packed),
127 be32_to_cpu(lvb->lvb_iattr));
128}
129
130
f625c979
MF		 131/*
132 * OCFS2 Lock Resource Operations
133 *
134 * These fine tune the behavior of the generic dlmglue locking infrastructure.
0d5dc6c2
MF		 135 *
136 * The most basic of lock types can point ->l_priv to their respective
137 * struct ocfs2_super and allow the default actions to manage things.
138 *
139 * Right now, each lock type also needs to implement an init function,
140 * and trivial lock/unlock wrappers. ocfs2_simple_drop_lockres()
141 * should be called when the lock is no longer needed (i.e., object
142 * destruction time).
f625c979 143 */
ccd979bd 144struct ocfs2_lock_res_ops {
54a7e755
MF		 145 /*
146 * Translate an ocfs2_lock_res * into an ocfs2_super *. Define
147 * this callback if ->l_priv is not an ocfs2_super pointer
148 */
149 struct ocfs2_super * (*get_osb)(struct ocfs2_lock_res *);
b5e500e2 150
0d5dc6c2 151 /*
34d024f8
MF		 152 * Optionally called in the downconvert thread after a
153 * successful downconvert. The lockres will not be referenced
154 * after this callback is called, so it is safe to free
155 * memory, etc.
0d5dc6c2
MF		 156 *
157 * The exact semantics of when this is called are controlled
158 * by ->downconvert_worker()
159 */
d680efe9 160 void (*post_unlock)(struct ocfs2_super *, struct ocfs2_lock_res *);
f625c979 161
16d5b956
MF		 162 /*
163 * Allow a lock type to add checks to determine whether it is
164 * safe to downconvert a lock. Return 0 to re-queue the
165 * downconvert at a later time, nonzero to continue.
166 *
167 * For most locks, the default checks that there are no
168 * incompatible holders are sufficient.
169 *
170 * Called with the lockres spinlock held.
171 */
172 int (*check_downconvert)(struct ocfs2_lock_res *, int);
173
5ef0d4ea
MF		 174 /*
175 * Allows a lock type to populate the lock value block. This
176 * is called on downconvert, and when we drop a lock.
177 *
178 * Locks that want to use this should set LOCK_TYPE_USES_LVB
179 * in the flags field.
180 *
181 * Called with the lockres spinlock held.
182 */
183 void (*set_lvb)(struct ocfs2_lock_res *);
184
cc567d89
MF		 185 /*
186 * Called from the downconvert thread when it is determined
187 * that a lock will be downconverted. This is called without
188 * any locks held so the function can do work that might
189 * schedule (syncing out data, etc).
190 *
191 * This should return any one of the ocfs2_unblock_action
192 * values, depending on what it wants the thread to do.
193 */
194 int (*downconvert_worker)(struct ocfs2_lock_res *, int);
195
f625c979
MF		 196 /*
197 * LOCK_TYPE_* flags which describe the specific requirements
198 * of a lock type. Descriptions of each individual flag follow.
199 */
200 int flags;
ccd979bd
MF		 201};
202
f625c979
MF		 203/*
204 * Some locks want to "refresh" potentially stale data when a
205 * meaningful (PRMODE or EXMODE) lock level is first obtained. If this
206 * flag is set, the OCFS2_LOCK_NEEDS_REFRESH flag will be set on the
207 * individual lockres l_flags member from the ast function. It is
208 * expected that the locking wrapper will clear the
209 * OCFS2_LOCK_NEEDS_REFRESH flag when done.
210 */
211#define LOCK_TYPE_REQUIRES_REFRESH 0x1
212
b80fc012 213/*
5ef0d4ea
MF		 214 * Indicate that a lock type makes use of the lock value block. The
215 * ->set_lvb lock type callback must be defined.
b80fc012
MF		 216 */
217#define LOCK_TYPE_USES_LVB 0x2
218
ccd979bd 219static struct ocfs2_lock_res_ops ocfs2_inode_rw_lops = {
54a7e755 220 .get_osb = ocfs2_get_inode_osb,
f625c979 221 .flags = 0,
ccd979bd
MF		 222};
223
e63aecb6 224static struct ocfs2_lock_res_ops ocfs2_inode_inode_lops = {
54a7e755 225 .get_osb = ocfs2_get_inode_osb,
810d5aeb
MF		 226 .check_downconvert = ocfs2_check_meta_downconvert,
227 .set_lvb = ocfs2_set_meta_lvb,
f1f54068 228 .downconvert_worker = ocfs2_data_convert_worker,
b80fc012 229 .flags = LOCK_TYPE_REQUIRES_REFRESH|LOCK_TYPE_USES_LVB,
ccd979bd
MF		 230};
231
ccd979bd 232static struct ocfs2_lock_res_ops ocfs2_super_lops = {
f625c979 233 .flags = LOCK_TYPE_REQUIRES_REFRESH,
ccd979bd
MF		 234};
235
236static struct ocfs2_lock_res_ops ocfs2_rename_lops = {
f625c979 237 .flags = 0,
ccd979bd
MF		 238};
239
d680efe9 240static struct ocfs2_lock_res_ops ocfs2_dentry_lops = {
54a7e755 241 .get_osb = ocfs2_get_dentry_osb,
d680efe9 242 .post_unlock = ocfs2_dentry_post_unlock,
cc567d89 243 .downconvert_worker = ocfs2_dentry_convert_worker,
f625c979 244 .flags = 0,
d680efe9
MF		 245};
246
50008630
TY		 247static struct ocfs2_lock_res_ops ocfs2_inode_open_lops = {
248 .get_osb = ocfs2_get_inode_osb,
249 .flags = 0,
250};
251
cf8e06f1
MF		 252static struct ocfs2_lock_res_ops ocfs2_flock_lops = {
253 .get_osb = ocfs2_get_file_osb,
254 .flags = 0,
255};
256
ccd979bd
MF		 257static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
258{
259 return lockres->l_type == OCFS2_LOCK_TYPE_META ||
50008630
TY		 260 lockres->l_type == OCFS2_LOCK_TYPE_RW ||
261 lockres->l_type == OCFS2_LOCK_TYPE_OPEN;
ccd979bd
MF		 262}
263
ccd979bd
MF		 264static inline struct inode *ocfs2_lock_res_inode(struct ocfs2_lock_res *lockres)
265{
266 BUG_ON(!ocfs2_is_inode_lock(lockres));
267
268 return (struct inode *) lockres->l_priv;
269}
270
d680efe9
MF		 271static inline struct ocfs2_dentry_lock *ocfs2_lock_res_dl(struct ocfs2_lock_res *lockres)
272{
273 BUG_ON(lockres->l_type != OCFS2_LOCK_TYPE_DENTRY);
274
275 return (struct ocfs2_dentry_lock *)lockres->l_priv;
276}
277
54a7e755
MF		 278static inline struct ocfs2_super *ocfs2_get_lockres_osb(struct ocfs2_lock_res *lockres)
279{
280 if (lockres->l_ops->get_osb)
281 return lockres->l_ops->get_osb(lockres);
282
283 return (struct ocfs2_super *)lockres->l_priv;
284}
285
ccd979bd
MF		 286static int ocfs2_lock_create(struct ocfs2_super *osb,
287 struct ocfs2_lock_res *lockres,
288 int level,
bd3e7610 289 u32 dlm_flags);
ccd979bd
MF		 290static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
291 int wanted);
292static void ocfs2_cluster_unlock(struct ocfs2_super *osb,
293 struct ocfs2_lock_res *lockres,
294 int level);
295static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres);
296static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres);
297static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres);
298static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres, int level);
299static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
300 struct ocfs2_lock_res *lockres);
301static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
302 int convert);
7431cd7e
JB		 303#define ocfs2_log_dlm_error(_func, _err, _lockres) do { \
304 mlog(ML_ERROR, "DLM error %d while calling %s on resource %s\n", \
305 _err, _func, _lockres->l_name); \
ccd979bd 306} while (0)
34d024f8
MF		 307static int ocfs2_downconvert_thread(void *arg);
308static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
309 struct ocfs2_lock_res *lockres);
e63aecb6 310static int ocfs2_inode_lock_update(struct inode *inode,
ccd979bd
MF		 311 struct buffer_head **bh);
312static void ocfs2_drop_osb_locks(struct ocfs2_super *osb);
313static inline int ocfs2_highest_compat_lock_level(int level);
cf8e06f1
MF		 314static void ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
315 int new_level);
316static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
317 struct ocfs2_lock_res *lockres,
318 int new_level,
319 int lvb);
320static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
321 struct ocfs2_lock_res *lockres);
322static int ocfs2_cancel_convert(struct ocfs2_super *osb,
323 struct ocfs2_lock_res *lockres);
324
ccd979bd 325
ccd979bd
MF		 326static void ocfs2_build_lock_name(enum ocfs2_lock_type type,
327 u64 blkno,
328 u32 generation,
329 char *name)
330{
331 int len;
332
333 mlog_entry_void();
334
335 BUG_ON(type >= OCFS2_NUM_LOCK_TYPES);
336
b0697053
MF		 337 len = snprintf(name, OCFS2_LOCK_ID_MAX_LEN, "%c%s%016llx%08x",
338 ocfs2_lock_type_char(type), OCFS2_LOCK_ID_PAD,
339 (long long)blkno, generation);
ccd979bd
MF		 340
341 BUG_ON(len != (OCFS2_LOCK_ID_MAX_LEN - 1));
342
343 mlog(0, "built lock resource with name: %s\n", name);
344
345 mlog_exit_void();
346}
347
34af946a 348static DEFINE_SPINLOCK(ocfs2_dlm_tracking_lock);
ccd979bd
MF		 349
350static void ocfs2_add_lockres_tracking(struct ocfs2_lock_res *res,
351 struct ocfs2_dlm_debug *dlm_debug)
352{
353 mlog(0, "Add tracking for lockres %s\n", res->l_name);
354
355 spin_lock(&ocfs2_dlm_tracking_lock);
356 list_add(&res->l_debug_list, &dlm_debug->d_lockres_tracking);
357 spin_unlock(&ocfs2_dlm_tracking_lock);
358}
359
360static void ocfs2_remove_lockres_tracking(struct ocfs2_lock_res *res)
361{
362 spin_lock(&ocfs2_dlm_tracking_lock);
363 if (!list_empty(&res->l_debug_list))
364 list_del_init(&res->l_debug_list);
365 spin_unlock(&ocfs2_dlm_tracking_lock);
366}
367
368static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
369 struct ocfs2_lock_res *res,
370 enum ocfs2_lock_type type,
ccd979bd
MF		 371 struct ocfs2_lock_res_ops *ops,
372 void *priv)
373{
ccd979bd
MF		 374 res->l_type = type;
375 res->l_ops = ops;
376 res->l_priv = priv;
377
bd3e7610
JB		 378 res->l_level = DLM_LOCK_IV;
379 res->l_requested = DLM_LOCK_IV;
380 res->l_blocking = DLM_LOCK_IV;
ccd979bd
MF		 381 res->l_action = OCFS2_AST_INVALID;
382 res->l_unlock_action = OCFS2_UNLOCK_INVALID;
383
384 res->l_flags = OCFS2_LOCK_INITIALIZED;
385
386 ocfs2_add_lockres_tracking(res, osb->osb_dlm_debug);
387}
388
389void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res)
390{
391 /* This also clears out the lock status block */
392 memset(res, 0, sizeof(struct ocfs2_lock_res));
393 spin_lock_init(&res->l_lock);
394 init_waitqueue_head(&res->l_event);
395 INIT_LIST_HEAD(&res->l_blocked_list);
396 INIT_LIST_HEAD(&res->l_mask_waiters);
397}
398
399void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
400 enum ocfs2_lock_type type,
24c19ef4 401 unsigned int generation,
ccd979bd
MF		 402 struct inode *inode)
403{
404 struct ocfs2_lock_res_ops *ops;
405
406 switch(type) {
407 case OCFS2_LOCK_TYPE_RW:
408 ops = &ocfs2_inode_rw_lops;
409 break;
410 case OCFS2_LOCK_TYPE_META:
e63aecb6 411 ops = &ocfs2_inode_inode_lops;
ccd979bd 412 break;
50008630
TY		 413 case OCFS2_LOCK_TYPE_OPEN:
414 ops = &ocfs2_inode_open_lops;
415 break;
ccd979bd
MF		 416 default:
417 mlog_bug_on_msg(1, "type: %d\n", type);
418 ops = NULL; /* thanks, gcc */
419 break;
420 };
421
d680efe9 422 ocfs2_build_lock_name(type, OCFS2_I(inode)->ip_blkno,
24c19ef4 423 generation, res->l_name);
d680efe9
MF		 424 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), res, type, ops, inode);
425}
426
54a7e755
MF		 427static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres)
428{
429 struct inode *inode = ocfs2_lock_res_inode(lockres);
430
431 return OCFS2_SB(inode->i_sb);
432}
433
cf8e06f1
MF		 434static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres)
435{
436 struct ocfs2_file_private *fp = lockres->l_priv;
437
438 return OCFS2_SB(fp->fp_file->f_mapping->host->i_sb);
439}
440
d680efe9
MF		 441static __u64 ocfs2_get_dentry_lock_ino(struct ocfs2_lock_res *lockres)
442{
443 __be64 inode_blkno_be;
444
445 memcpy(&inode_blkno_be, &lockres->l_name[OCFS2_DENTRY_LOCK_INO_START],
446 sizeof(__be64));
447
448 return be64_to_cpu(inode_blkno_be);
449}
450
54a7e755
MF		 451static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres)
452{
453 struct ocfs2_dentry_lock *dl = lockres->l_priv;
454
455 return OCFS2_SB(dl->dl_inode->i_sb);
456}
457
d680efe9
MF		 458void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
459 u64 parent, struct inode *inode)
460{
461 int len;
462 u64 inode_blkno = OCFS2_I(inode)->ip_blkno;
463 __be64 inode_blkno_be = cpu_to_be64(inode_blkno);
464 struct ocfs2_lock_res *lockres = &dl->dl_lockres;
465
466 ocfs2_lock_res_init_once(lockres);
467
468 /*
469 * Unfortunately, the standard lock naming scheme won't work
470 * here because we have two 16 byte values to use. Instead,
471 * we'll stuff the inode number as a binary value. We still
472 * want error prints to show something without garbling the
473 * display, so drop a null byte in there before the inode
474 * number. A future version of OCFS2 will likely use all
475 * binary lock names. The stringified names have been a
476 * tremendous aid in debugging, but now that the debugfs
477 * interface exists, we can mangle things there if need be.
478 *
479 * NOTE: We also drop the standard "pad" value (the total lock
480 * name size stays the same though - the last part is all
481 * zeros due to the memset in ocfs2_lock_res_init_once()
482 */
483 len = snprintf(lockres->l_name, OCFS2_DENTRY_LOCK_INO_START,
484 "%c%016llx",
485 ocfs2_lock_type_char(OCFS2_LOCK_TYPE_DENTRY),
486 (long long)parent);
487
488 BUG_ON(len != (OCFS2_DENTRY_LOCK_INO_START - 1));
489
490 memcpy(&lockres->l_name[OCFS2_DENTRY_LOCK_INO_START], &inode_blkno_be,
491 sizeof(__be64));
492
493 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
494 OCFS2_LOCK_TYPE_DENTRY, &ocfs2_dentry_lops,
495 dl);
ccd979bd
MF		 496}
497
498static void ocfs2_super_lock_res_init(struct ocfs2_lock_res *res,
499 struct ocfs2_super *osb)
500{
501 /* Superblock lockres doesn't come from a slab so we call init
502 * once on it manually. */
503 ocfs2_lock_res_init_once(res);
d680efe9
MF		 504 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_SUPER, OCFS2_SUPER_BLOCK_BLKNO,
505 0, res->l_name);
ccd979bd 506 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_SUPER,
ccd979bd
MF		 507 &ocfs2_super_lops, osb);
508}
509
510static void ocfs2_rename_lock_res_init(struct ocfs2_lock_res *res,
511 struct ocfs2_super *osb)
512{
513 /* Rename lockres doesn't come from a slab so we call init
514 * once on it manually. */
515 ocfs2_lock_res_init_once(res);
d680efe9
MF		 516 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_RENAME, 0, 0, res->l_name);
517 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_RENAME,
ccd979bd
MF		 518 &ocfs2_rename_lops, osb);
519}
520
cf8e06f1
MF		 521void ocfs2_file_lock_res_init(struct ocfs2_lock_res *lockres,
522 struct ocfs2_file_private *fp)
523{
524 struct inode *inode = fp->fp_file->f_mapping->host;
525 struct ocfs2_inode_info *oi = OCFS2_I(inode);
526
527 ocfs2_lock_res_init_once(lockres);
528 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_FLOCK, oi->ip_blkno,
529 inode->i_generation, lockres->l_name);
530 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
531 OCFS2_LOCK_TYPE_FLOCK, &ocfs2_flock_lops,
532 fp);
533 lockres->l_flags |= OCFS2_LOCK_NOCACHE;
534}
535
ccd979bd
MF		 536void ocfs2_lock_res_free(struct ocfs2_lock_res *res)
537{
538 mlog_entry_void();
539
540 if (!(res->l_flags & OCFS2_LOCK_INITIALIZED))
541 return;
542
543 ocfs2_remove_lockres_tracking(res);
544
545 mlog_bug_on_msg(!list_empty(&res->l_blocked_list),
546 "Lockres %s is on the blocked list\n",
547 res->l_name);
548 mlog_bug_on_msg(!list_empty(&res->l_mask_waiters),
549 "Lockres %s has mask waiters pending\n",
550 res->l_name);
551 mlog_bug_on_msg(spin_is_locked(&res->l_lock),
552 "Lockres %s is locked\n",
553 res->l_name);
554 mlog_bug_on_msg(res->l_ro_holders,
555 "Lockres %s has %u ro holders\n",
556 res->l_name, res->l_ro_holders);
557 mlog_bug_on_msg(res->l_ex_holders,
558 "Lockres %s has %u ex holders\n",
559 res->l_name, res->l_ex_holders);
560
561 /* Need to clear out the lock status block for the dlm */
562 memset(&res->l_lksb, 0, sizeof(res->l_lksb));
563
564 res->l_flags = 0UL;
565 mlog_exit_void();
566}
567
568static inline void ocfs2_inc_holders(struct ocfs2_lock_res *lockres,
569 int level)
570{
571 mlog_entry_void();
572
573 BUG_ON(!lockres);
574
575 switch(level) {
bd3e7610 576 case DLM_LOCK_EX:
ccd979bd
MF		 577 lockres->l_ex_holders++;
578 break;
bd3e7610 579 case DLM_LOCK_PR:
ccd979bd
MF		 580 lockres->l_ro_holders++;
581 break;
582 default:
583 BUG();
584 }
585
586 mlog_exit_void();
587}
588
589static inline void ocfs2_dec_holders(struct ocfs2_lock_res *lockres,
590 int level)
591{
592 mlog_entry_void();
593
594 BUG_ON(!lockres);
595
596 switch(level) {
bd3e7610 597 case DLM_LOCK_EX:
ccd979bd
MF		 598 BUG_ON(!lockres->l_ex_holders);
599 lockres->l_ex_holders--;
600 break;
bd3e7610 601 case DLM_LOCK_PR:
ccd979bd
MF		 602 BUG_ON(!lockres->l_ro_holders);
603 lockres->l_ro_holders--;
604 break;
605 default:
606 BUG();
607 }
608 mlog_exit_void();
609}
610
611/* WARNING: This function lives in a world where the only three lock
612 * levels are EX, PR, and NL. It *will* have to be adjusted when more
613 * lock types are added. */
614static inline int ocfs2_highest_compat_lock_level(int level)
615{
bd3e7610 616 int new_level = DLM_LOCK_EX;
ccd979bd 617
bd3e7610
JB		 618 if (level == DLM_LOCK_EX)
619 new_level = DLM_LOCK_NL;
620 else if (level == DLM_LOCK_PR)
621 new_level = DLM_LOCK_PR;
ccd979bd
MF		 622 return new_level;
623}
624
625static void lockres_set_flags(struct ocfs2_lock_res *lockres,
626 unsigned long newflags)
627{
800deef3 628 struct ocfs2_mask_waiter *mw, *tmp;
ccd979bd
MF		 629
630 assert_spin_locked(&lockres->l_lock);
631
632 lockres->l_flags = newflags;
633
800deef3 634 list_for_each_entry_safe(mw, tmp, &lockres->l_mask_waiters, mw_item) {
ccd979bd
MF		 635 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
636 continue;
637
638 list_del_init(&mw->mw_item);
639 mw->mw_status = 0;
640 complete(&mw->mw_complete);
641 }
642}
643static void lockres_or_flags(struct ocfs2_lock_res *lockres, unsigned long or)
644{
645 lockres_set_flags(lockres, lockres->l_flags | or);
646}
647static void lockres_clear_flags(struct ocfs2_lock_res *lockres,
648 unsigned long clear)
649{
650 lockres_set_flags(lockres, lockres->l_flags & ~clear);
651}
652
653static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres)
654{
655 mlog_entry_void();
656
657 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
658 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
659 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
bd3e7610 660 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
ccd979bd
MF		 661
662 lockres->l_level = lockres->l_requested;
663 if (lockres->l_level <=
664 ocfs2_highest_compat_lock_level(lockres->l_blocking)) {
bd3e7610 665 lockres->l_blocking = DLM_LOCK_NL;
ccd979bd
MF		 666 lockres_clear_flags(lockres, OCFS2_LOCK_BLOCKED);
667 }
668 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
669
670 mlog_exit_void();
671}
672
673static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres)
674{
675 mlog_entry_void();
676
677 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
678 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
679
680 /* Convert from RO to EX doesn't really need anything as our
681 * information is already up to data. Convert from NL to
682 * *anything* however should mark ourselves as needing an
683 * update */
bd3e7610 684 if (lockres->l_level == DLM_LOCK_NL &&
f625c979 685 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
ccd979bd
MF		 686 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
687
688 lockres->l_level = lockres->l_requested;
689 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
690
691 mlog_exit_void();
692}
693
694static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres)
695{
696 mlog_entry_void();
697
3cf0c507 698 BUG_ON((!(lockres->l_flags & OCFS2_LOCK_BUSY)));
ccd979bd
MF		 699 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
700
bd3e7610 701 if (lockres->l_requested > DLM_LOCK_NL &&
f625c979
MF		 702 !(lockres->l_flags & OCFS2_LOCK_LOCAL) &&
703 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
ccd979bd
MF		 704 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
705
706 lockres->l_level = lockres->l_requested;
707 lockres_or_flags(lockres, OCFS2_LOCK_ATTACHED);
708 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
709
710 mlog_exit_void();
711}
712
ccd979bd
MF		 713static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres,
714 int level)
715{
716 int needs_downconvert = 0;
717 mlog_entry_void();
718
719 assert_spin_locked(&lockres->l_lock);
720
721 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
722
723 if (level > lockres->l_blocking) {
724 /* only schedule a downconvert if we haven't already scheduled
725 * one that goes low enough to satisfy the level we're
726 * blocking. this also catches the case where we get
727 * duplicate BASTs */
728 if (ocfs2_highest_compat_lock_level(level) <
729 ocfs2_highest_compat_lock_level(lockres->l_blocking))
730 needs_downconvert = 1;
731
732 lockres->l_blocking = level;
733 }
734
735 mlog_exit(needs_downconvert);
736 return needs_downconvert;
737}
738
aa2623ad 739static void ocfs2_blocking_ast(void *opaque, int level)
ccd979bd 740{
aa2623ad
MF		 741 struct ocfs2_lock_res *lockres = opaque;
742 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
ccd979bd
MF		 743 int needs_downconvert;
744 unsigned long flags;
745
bd3e7610 746 BUG_ON(level <= DLM_LOCK_NL);
ccd979bd 747
aa2623ad
MF		 748 mlog(0, "BAST fired for lockres %s, blocking %d, level %d type %s\n",
749 lockres->l_name, level, lockres->l_level,
750 ocfs2_lock_type_string(lockres->l_type));
751
cf8e06f1
MF		 752 /*
753 * We can skip the bast for locks which don't enable caching -
754 * they'll be dropped at the earliest possible time anyway.
755 */
756 if (lockres->l_flags & OCFS2_LOCK_NOCACHE)
757 return;
758
ccd979bd
MF		 759 spin_lock_irqsave(&lockres->l_lock, flags);
760 needs_downconvert = ocfs2_generic_handle_bast(lockres, level);
761 if (needs_downconvert)
762 ocfs2_schedule_blocked_lock(osb, lockres);
763 spin_unlock_irqrestore(&lockres->l_lock, flags);
764
d680efe9
MF		 765 wake_up(&lockres->l_event);
766
34d024f8 767 ocfs2_wake_downconvert_thread(osb);
ccd979bd
MF		 768}
769
e92d57df 770static void ocfs2_locking_ast(void *opaque)
ccd979bd 771{
e92d57df 772 struct ocfs2_lock_res *lockres = opaque;
ccd979bd
MF		 773 unsigned long flags;
774
775 spin_lock_irqsave(&lockres->l_lock, flags);
776
8f2c9c1b
JB		 777 if (ocfs2_dlm_lock_status(&lockres->l_lksb)) {
778 mlog(ML_ERROR, "lockres %s: lksb status value of %d!\n",
779 lockres->l_name,
780 ocfs2_dlm_lock_status(&lockres->l_lksb));
ccd979bd
MF		 781 spin_unlock_irqrestore(&lockres->l_lock, flags);
782 return;
783 }
784
785 switch(lockres->l_action) {
786 case OCFS2_AST_ATTACH:
787 ocfs2_generic_handle_attach_action(lockres);
e92d57df 788 lockres_clear_flags(lockres, OCFS2_LOCK_LOCAL);
ccd979bd
MF		 789 break;
790 case OCFS2_AST_CONVERT:
791 ocfs2_generic_handle_convert_action(lockres);
792 break;
793 case OCFS2_AST_DOWNCONVERT:
794 ocfs2_generic_handle_downconvert_action(lockres);
795 break;
796 default:
e92d57df
MF		 797 mlog(ML_ERROR, "lockres %s: ast fired with invalid action: %u "
798 "lockres flags = 0x%lx, unlock action: %u\n",
799 lockres->l_name, lockres->l_action, lockres->l_flags,
800 lockres->l_unlock_action);
ccd979bd
MF		 801 BUG();
802 }
803
ccd979bd
MF		 804 /* set it to something invalid so if we get called again we
805 * can catch it. */
806 lockres->l_action = OCFS2_AST_INVALID;
ccd979bd
MF		 807
808 wake_up(&lockres->l_event);
d680efe9 809 spin_unlock_irqrestore(&lockres->l_lock, flags);
ccd979bd
MF		 810}
811
ccd979bd
MF		 812static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
813 int convert)
814{
815 unsigned long flags;
816
817 mlog_entry_void();
818 spin_lock_irqsave(&lockres->l_lock, flags);
819 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
820 if (convert)
821 lockres->l_action = OCFS2_AST_INVALID;
822 else
823 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
824 spin_unlock_irqrestore(&lockres->l_lock, flags);
825
826 wake_up(&lockres->l_event);
827 mlog_exit_void();
828}
829
830/* Note: If we detect another process working on the lock (i.e.,
831 * OCFS2_LOCK_BUSY), we'll bail out returning 0. It's up to the caller
832 * to do the right thing in that case.
833 */
834static int ocfs2_lock_create(struct ocfs2_super *osb,
835 struct ocfs2_lock_res *lockres,
836 int level,
bd3e7610 837 u32 dlm_flags)
ccd979bd
MF		 838{
839 int ret = 0;
ccd979bd
MF		 840 unsigned long flags;
841
842 mlog_entry_void();
843
bd3e7610 844 mlog(0, "lock %s, level = %d, flags = %u\n", lockres->l_name, level,
ccd979bd
MF		 845 dlm_flags);
846
847 spin_lock_irqsave(&lockres->l_lock, flags);
848 if ((lockres->l_flags & OCFS2_LOCK_ATTACHED) ||
849 (lockres->l_flags & OCFS2_LOCK_BUSY)) {
850 spin_unlock_irqrestore(&lockres->l_lock, flags);
851 goto bail;
852 }
853
854 lockres->l_action = OCFS2_AST_ATTACH;
855 lockres->l_requested = level;
856 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
857 spin_unlock_irqrestore(&lockres->l_lock, flags);
858
4670c46d 859 ret = ocfs2_dlm_lock(osb->cconn,
7431cd7e
JB		 860 level,
861 &lockres->l_lksb,
862 dlm_flags,
863 lockres->l_name,
864 OCFS2_LOCK_ID_MAX_LEN - 1,
865 lockres);
866 if (ret) {
867 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
ccd979bd
MF		 868 ocfs2_recover_from_dlm_error(lockres, 1);
869 }
870
7431cd7e 871 mlog(0, "lock %s, return from ocfs2_dlm_lock\n", lockres->l_name);
ccd979bd
MF		 872
873bail:
874 mlog_exit(ret);
875 return ret;
876}
877
878static inline int ocfs2_check_wait_flag(struct ocfs2_lock_res *lockres,
879 int flag)
880{
881 unsigned long flags;
882 int ret;
883
884 spin_lock_irqsave(&lockres->l_lock, flags);
885 ret = lockres->l_flags & flag;
886 spin_unlock_irqrestore(&lockres->l_lock, flags);
887
888 return ret;
889}
890
891static inline void ocfs2_wait_on_busy_lock(struct ocfs2_lock_res *lockres)
892
893{
894 wait_event(lockres->l_event,
895 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_BUSY));
896}
897
898static inline void ocfs2_wait_on_refreshing_lock(struct ocfs2_lock_res *lockres)
899
900{
901 wait_event(lockres->l_event,
902 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_REFRESHING));
903}
904
905/* predict what lock level we'll be dropping down to on behalf
906 * of another node, and return true if the currently wanted
907 * level will be compatible with it. */
908static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
909 int wanted)
910{
911 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
912
913 return wanted <= ocfs2_highest_compat_lock_level(lockres->l_blocking);
914}
915
916static void ocfs2_init_mask_waiter(struct ocfs2_mask_waiter *mw)
917{
918 INIT_LIST_HEAD(&mw->mw_item);
919 init_completion(&mw->mw_complete);
920}
921
922static int ocfs2_wait_for_mask(struct ocfs2_mask_waiter *mw)
923{
924 wait_for_completion(&mw->mw_complete);
925 /* Re-arm the completion in case we want to wait on it again */
926 INIT_COMPLETION(mw->mw_complete);
927 return mw->mw_status;
928}
929
930static void lockres_add_mask_waiter(struct ocfs2_lock_res *lockres,
931 struct ocfs2_mask_waiter *mw,
932 unsigned long mask,
933 unsigned long goal)
934{
935 BUG_ON(!list_empty(&mw->mw_item));
936
937 assert_spin_locked(&lockres->l_lock);
938
939 list_add_tail(&mw->mw_item, &lockres->l_mask_waiters);
940 mw->mw_mask = mask;
941 mw->mw_goal = goal;
942}
943
944/* returns 0 if the mw that was removed was already satisfied, -EBUSY
945 * if the mask still hadn't reached its goal */
946static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
947 struct ocfs2_mask_waiter *mw)
948{
949 unsigned long flags;
950 int ret = 0;
951
952 spin_lock_irqsave(&lockres->l_lock, flags);
953 if (!list_empty(&mw->mw_item)) {
954 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
955 ret = -EBUSY;
956
957 list_del_init(&mw->mw_item);
958 init_completion(&mw->mw_complete);
959 }
960 spin_unlock_irqrestore(&lockres->l_lock, flags);
961
962 return ret;
963
964}
965
cf8e06f1
MF		 966static int ocfs2_wait_for_mask_interruptible(struct ocfs2_mask_waiter *mw,
967 struct ocfs2_lock_res *lockres)
968{
969 int ret;
970
971 ret = wait_for_completion_interruptible(&mw->mw_complete);
972 if (ret)
973 lockres_remove_mask_waiter(lockres, mw);
974 else
975 ret = mw->mw_status;
976 /* Re-arm the completion in case we want to wait on it again */
977 INIT_COMPLETION(mw->mw_complete);
978 return ret;
979}
980
ccd979bd
MF		 981static int ocfs2_cluster_lock(struct ocfs2_super *osb,
982 struct ocfs2_lock_res *lockres,
983 int level,
bd3e7610 984 u32 lkm_flags,
ccd979bd
MF		 985 int arg_flags)
986{
987 struct ocfs2_mask_waiter mw;
ccd979bd
MF		 988 int wait, catch_signals = !(osb->s_mount_opt & OCFS2_MOUNT_NOINTR);
989 int ret = 0; /* gcc doesn't realize wait = 1 guarantees ret is set */
990 unsigned long flags;
991
992 mlog_entry_void();
993
994 ocfs2_init_mask_waiter(&mw);
995
b80fc012 996 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
bd3e7610 997 lkm_flags |= DLM_LKF_VALBLK;
b80fc012 998
ccd979bd
MF		 999again:
1000 wait = 0;
1001
1002 if (catch_signals && signal_pending(current)) {
1003 ret = -ERESTARTSYS;
1004 goto out;
1005 }
1006
1007 spin_lock_irqsave(&lockres->l_lock, flags);
1008
1009 mlog_bug_on_msg(lockres->l_flags & OCFS2_LOCK_FREEING,
1010 "Cluster lock called on freeing lockres %s! flags "
1011 "0x%lx\n", lockres->l_name, lockres->l_flags);
1012
1013 /* We only compare against the currently granted level
1014 * here. If the lock is blocked waiting on a downconvert,
1015 * we'll get caught below. */
1016 if (lockres->l_flags & OCFS2_LOCK_BUSY &&
1017 level > lockres->l_level) {
1018 /* is someone sitting in dlm_lock? If so, wait on
1019 * them. */
1020 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1021 wait = 1;
1022 goto unlock;
1023 }
1024
ccd979bd
MF		 1025 if (lockres->l_flags & OCFS2_LOCK_BLOCKED &&
1026 !ocfs2_may_continue_on_blocked_lock(lockres, level)) {
1027 /* is the lock is currently blocked on behalf of
1028 * another node */
1029 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BLOCKED, 0);
1030 wait = 1;
1031 goto unlock;
1032 }
1033
1034 if (level > lockres->l_level) {
1035 if (lockres->l_action != OCFS2_AST_INVALID)
1036 mlog(ML_ERROR, "lockres %s has action %u pending\n",
1037 lockres->l_name, lockres->l_action);
1038
019d1b22
MF		 1039 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1040 lockres->l_action = OCFS2_AST_ATTACH;
bd3e7610 1041 lkm_flags &= ~DLM_LKF_CONVERT;
019d1b22
MF		 1042 } else {
1043 lockres->l_action = OCFS2_AST_CONVERT;
bd3e7610 1044 lkm_flags |= DLM_LKF_CONVERT;
019d1b22
MF		 1045 }
1046
ccd979bd
MF		 1047 lockres->l_requested = level;
1048 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1049 spin_unlock_irqrestore(&lockres->l_lock, flags);
1050
bd3e7610
JB		 1051 BUG_ON(level == DLM_LOCK_IV);
1052 BUG_ON(level == DLM_LOCK_NL);
ccd979bd
MF		 1053
1054 mlog(0, "lock %s, convert from %d to level = %d\n",
1055 lockres->l_name, lockres->l_level, level);
1056
1057 /* call dlm_lock to upgrade lock now */
4670c46d 1058 ret = ocfs2_dlm_lock(osb->cconn,
7431cd7e
JB		 1059 level,
1060 &lockres->l_lksb,
1061 lkm_flags,
1062 lockres->l_name,
1063 OCFS2_LOCK_ID_MAX_LEN - 1,
1064 lockres);
1065 if (ret) {
1066 if (!(lkm_flags & DLM_LKF_NOQUEUE) ||
1067 (ret != -EAGAIN)) {
24ef1815 1068 ocfs2_log_dlm_error("ocfs2_dlm_lock",
7431cd7e 1069 ret, lockres);
ccd979bd
MF		 1070 }
1071 ocfs2_recover_from_dlm_error(lockres, 1);
1072 goto out;
1073 }
1074
24ef1815 1075 mlog(0, "lock %s, successfull return from ocfs2_dlm_lock\n",
ccd979bd
MF		 1076 lockres->l_name);
1077
1078 /* At this point we've gone inside the dlm and need to
1079 * complete our work regardless. */
1080 catch_signals = 0;
1081
1082 /* wait for busy to clear and carry on */
1083 goto again;
1084 }
1085
1086 /* Ok, if we get here then we're good to go. */
1087 ocfs2_inc_holders(lockres, level);
1088
1089 ret = 0;
1090unlock:
1091 spin_unlock_irqrestore(&lockres->l_lock, flags);
1092out:
1093 /*
1094 * This is helping work around a lock inversion between the page lock
1095 * and dlm locks. One path holds the page lock while calling aops
1096 * which block acquiring dlm locks. The voting thread holds dlm
1097 * locks while acquiring page locks while down converting data locks.
1098 * This block is helping an aop path notice the inversion and back
1099 * off to unlock its page lock before trying the dlm lock again.
1100 */
1101 if (wait && arg_flags & OCFS2_LOCK_NONBLOCK &&
1102 mw.mw_mask & (OCFS2_LOCK_BUSY|OCFS2_LOCK_BLOCKED)) {
1103 wait = 0;
1104 if (lockres_remove_mask_waiter(lockres, &mw))
1105 ret = -EAGAIN;
1106 else
1107 goto again;
1108 }
1109 if (wait) {
1110 ret = ocfs2_wait_for_mask(&mw);
1111 if (ret == 0)
1112 goto again;
1113 mlog_errno(ret);
1114 }
1115
1116 mlog_exit(ret);
1117 return ret;
1118}
1119
1120static void ocfs2_cluster_unlock(struct ocfs2_super *osb,
1121 struct ocfs2_lock_res *lockres,
1122 int level)
1123{
1124 unsigned long flags;
1125
1126 mlog_entry_void();
1127 spin_lock_irqsave(&lockres->l_lock, flags);
1128 ocfs2_dec_holders(lockres, level);
34d024f8 1129 ocfs2_downconvert_on_unlock(osb, lockres);
ccd979bd
MF		 1130 spin_unlock_irqrestore(&lockres->l_lock, flags);
1131 mlog_exit_void();
1132}
1133
da66116e
AB		 1134static int ocfs2_create_new_lock(struct ocfs2_super *osb,
1135 struct ocfs2_lock_res *lockres,
1136 int ex,
1137 int local)
ccd979bd 1138{
bd3e7610 1139 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 1140 unsigned long flags;
bd3e7610 1141 u32 lkm_flags = local ? DLM_LKF_LOCAL : 0;
ccd979bd
MF		 1142
1143 spin_lock_irqsave(&lockres->l_lock, flags);
1144 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
1145 lockres_or_flags(lockres, OCFS2_LOCK_LOCAL);
1146 spin_unlock_irqrestore(&lockres->l_lock, flags);
1147
24c19ef4 1148 return ocfs2_lock_create(osb, lockres, level, lkm_flags);
ccd979bd
MF		 1149}
1150
1151/* Grants us an EX lock on the data and metadata resources, skipping
1152 * the normal cluster directory lookup. Use this ONLY on newly created
1153 * inodes which other nodes can't possibly see, and which haven't been
1154 * hashed in the inode hash yet. This can give us a good performance
1155 * increase as it'll skip the network broadcast normally associated
1156 * with creating a new lock resource. */
1157int ocfs2_create_new_inode_locks(struct inode *inode)
1158{
1159 int ret;
d680efe9 1160 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1161
1162 BUG_ON(!inode);
1163 BUG_ON(!ocfs2_inode_is_new(inode));
1164
1165 mlog_entry_void();
1166
b0697053 1167 mlog(0, "Inode %llu\n", (unsigned long long)OCFS2_I(inode)->ip_blkno);
ccd979bd
MF		 1168
1169 /* NOTE: That we don't increment any of the holder counts, nor
1170 * do we add anything to a journal handle. Since this is
1171 * supposed to be a new inode which the cluster doesn't know
1172 * about yet, there is no need to. As far as the LVB handling
1173 * is concerned, this is basically like acquiring an EX lock
1174 * on a resource which has an invalid one -- we'll set it
1175 * valid when we release the EX. */
1176
24c19ef4 1177 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_rw_lockres, 1, 1);
ccd979bd
MF		 1178 if (ret) {
1179 mlog_errno(ret);
1180 goto bail;
1181 }
1182
24c19ef4 1183 /*
bd3e7610 1184 * We don't want to use DLM_LKF_LOCAL on a meta data lock as they
24c19ef4
MF		 1185 * don't use a generation in their lock names.
1186 */
e63aecb6 1187 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_inode_lockres, 1, 0);
ccd979bd
MF		 1188 if (ret) {
1189 mlog_errno(ret);
1190 goto bail;
1191 }
1192
50008630
TY		 1193 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_open_lockres, 0, 0);
1194 if (ret) {
1195 mlog_errno(ret);
1196 goto bail;
1197 }
1198
ccd979bd
MF		 1199bail:
1200 mlog_exit(ret);
1201 return ret;
1202}
1203
1204int ocfs2_rw_lock(struct inode *inode, int write)
1205{
1206 int status, level;
1207 struct ocfs2_lock_res *lockres;
c271c5c2 1208 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1209
1210 BUG_ON(!inode);
1211
1212 mlog_entry_void();
1213
b0697053
MF		 1214 mlog(0, "inode %llu take %s RW lock\n",
1215 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1216 write ? "EXMODE" : "PRMODE");
1217
c271c5c2
SM		 1218 if (ocfs2_mount_local(osb))
1219 return 0;
1220
ccd979bd
MF		 1221 lockres = &OCFS2_I(inode)->ip_rw_lockres;
1222
bd3e7610 1223 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 1224
1225 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres, level, 0,
1226 0);
1227 if (status < 0)
1228 mlog_errno(status);
1229
1230 mlog_exit(status);
1231 return status;
1232}
1233
1234void ocfs2_rw_unlock(struct inode *inode, int write)
1235{
bd3e7610 1236 int level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 1237 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_rw_lockres;
c271c5c2 1238 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1239
1240 mlog_entry_void();
1241
b0697053
MF		 1242 mlog(0, "inode %llu drop %s RW lock\n",
1243 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1244 write ? "EXMODE" : "PRMODE");
1245
c271c5c2
SM		 1246 if (!ocfs2_mount_local(osb))
1247 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
ccd979bd
MF		 1248
1249 mlog_exit_void();
1250}
1251
50008630
TY		 1252/*
1253 * ocfs2_open_lock always get PR mode lock.
1254 */
1255int ocfs2_open_lock(struct inode *inode)
1256{
1257 int status = 0;
1258 struct ocfs2_lock_res *lockres;
1259 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1260
1261 BUG_ON(!inode);
1262
1263 mlog_entry_void();
1264
1265 mlog(0, "inode %llu take PRMODE open lock\n",
1266 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1267
1268 if (ocfs2_mount_local(osb))
1269 goto out;
1270
1271 lockres = &OCFS2_I(inode)->ip_open_lockres;
1272
1273 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1274 DLM_LOCK_PR, 0, 0);
50008630
TY		 1275 if (status < 0)
1276 mlog_errno(status);
1277
1278out:
1279 mlog_exit(status);
1280 return status;
1281}
1282
1283int ocfs2_try_open_lock(struct inode *inode, int write)
1284{
1285 int status = 0, level;
1286 struct ocfs2_lock_res *lockres;
1287 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1288
1289 BUG_ON(!inode);
1290
1291 mlog_entry_void();
1292
1293 mlog(0, "inode %llu try to take %s open lock\n",
1294 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1295 write ? "EXMODE" : "PRMODE");
1296
1297 if (ocfs2_mount_local(osb))
1298 goto out;
1299
1300 lockres = &OCFS2_I(inode)->ip_open_lockres;
1301
bd3e7610 1302 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
50008630
TY		 1303
1304 /*
1305 * The file system may already holding a PRMODE/EXMODE open lock.
bd3e7610 1306 * Since we pass DLM_LKF_NOQUEUE, the request won't block waiting on
50008630
TY		 1307 * other nodes and the -EAGAIN will indicate to the caller that
1308 * this inode is still in use.
1309 */
1310 status = ocfs2_cluster_lock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1311 level, DLM_LKF_NOQUEUE, 0);
50008630
TY		 1312
1313out:
1314 mlog_exit(status);
1315 return status;
1316}
1317
1318/*
1319 * ocfs2_open_unlock unlock PR and EX mode open locks.
1320 */
1321void ocfs2_open_unlock(struct inode *inode)
1322{
1323 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_open_lockres;
1324 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1325
1326 mlog_entry_void();
1327
1328 mlog(0, "inode %llu drop open lock\n",
1329 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1330
1331 if (ocfs2_mount_local(osb))
1332 goto out;
1333
1334 if(lockres->l_ro_holders)
1335 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1336 DLM_LOCK_PR);
50008630
TY		 1337 if(lockres->l_ex_holders)
1338 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres,
bd3e7610 1339 DLM_LOCK_EX);
50008630
TY		 1340
1341out:
1342 mlog_exit_void();
1343}
1344
cf8e06f1
MF		 1345static int ocfs2_flock_handle_signal(struct ocfs2_lock_res *lockres,
1346 int level)
1347{
1348 int ret;
1349 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
1350 unsigned long flags;
1351 struct ocfs2_mask_waiter mw;
1352
1353 ocfs2_init_mask_waiter(&mw);
1354
1355retry_cancel:
1356 spin_lock_irqsave(&lockres->l_lock, flags);
1357 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
1358 ret = ocfs2_prepare_cancel_convert(osb, lockres);
1359 if (ret) {
1360 spin_unlock_irqrestore(&lockres->l_lock, flags);
1361 ret = ocfs2_cancel_convert(osb, lockres);
1362 if (ret < 0) {
1363 mlog_errno(ret);
1364 goto out;
1365 }
1366 goto retry_cancel;
1367 }
1368 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1369 spin_unlock_irqrestore(&lockres->l_lock, flags);
1370
1371 ocfs2_wait_for_mask(&mw);
1372 goto retry_cancel;
1373 }
1374
1375 ret = -ERESTARTSYS;
1376 /*
1377 * We may still have gotten the lock, in which case there's no
1378 * point to restarting the syscall.
1379 */
1380 if (lockres->l_level == level)
1381 ret = 0;
1382
1383 mlog(0, "Cancel returning %d. flags: 0x%lx, level: %d, act: %d\n", ret,
1384 lockres->l_flags, lockres->l_level, lockres->l_action);
1385
1386 spin_unlock_irqrestore(&lockres->l_lock, flags);
1387
1388out:
1389 return ret;
1390}
1391
1392/*
1393 * ocfs2_file_lock() and ocfs2_file_unlock() map to a single pair of
1394 * flock() calls. The locking approach this requires is sufficiently
1395 * different from all other cluster lock types that we implement a
1396 * seperate path to the "low-level" dlm calls. In particular:
1397 *
1398 * - No optimization of lock levels is done - we take at exactly
1399 * what's been requested.
1400 *
1401 * - No lock caching is employed. We immediately downconvert to
1402 * no-lock at unlock time. This also means flock locks never go on
1403 * the blocking list).
1404 *
1405 * - Since userspace can trivially deadlock itself with flock, we make
1406 * sure to allow cancellation of a misbehaving applications flock()
1407 * request.
1408 *
1409 * - Access to any flock lockres doesn't require concurrency, so we
1410 * can simplify the code by requiring the caller to guarantee
1411 * serialization of dlmglue flock calls.
1412 */
1413int ocfs2_file_lock(struct file *file, int ex, int trylock)
1414{
1415 int ret, level = ex ? LKM_EXMODE : LKM_PRMODE;
1416 unsigned int lkm_flags = trylock ? LKM_NOQUEUE : 0;
1417 unsigned long flags;
1418 struct ocfs2_file_private *fp = file->private_data;
1419 struct ocfs2_lock_res *lockres = &fp->fp_flock;
1420 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
1421 struct ocfs2_mask_waiter mw;
1422
1423 ocfs2_init_mask_waiter(&mw);
1424
1425 if ((lockres->l_flags & OCFS2_LOCK_BUSY) ||
bd3e7610 1426 (lockres->l_level > DLM_LOCK_NL)) {
cf8e06f1
MF		 1427 mlog(ML_ERROR,
1428 "File lock \"%s\" has busy or locked state: flags: 0x%lx, "
1429 "level: %u\n", lockres->l_name, lockres->l_flags,
1430 lockres->l_level);
1431 return -EINVAL;
1432 }
1433
1434 spin_lock_irqsave(&lockres->l_lock, flags);
1435 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1436 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1437 spin_unlock_irqrestore(&lockres->l_lock, flags);
1438
1439 /*
1440 * Get the lock at NLMODE to start - that way we
1441 * can cancel the upconvert request if need be.
1442 */
1443 ret = ocfs2_lock_create(osb, lockres, LKM_NLMODE, 0);
1444 if (ret < 0) {
1445 mlog_errno(ret);
1446 goto out;
1447 }
1448
1449 ret = ocfs2_wait_for_mask(&mw);
1450 if (ret) {
1451 mlog_errno(ret);
1452 goto out;
1453 }
1454 spin_lock_irqsave(&lockres->l_lock, flags);
1455 }
1456
1457 lockres->l_action = OCFS2_AST_CONVERT;
1458 lkm_flags |= LKM_CONVERT;
1459 lockres->l_requested = level;
1460 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1461
1462 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1463 spin_unlock_irqrestore(&lockres->l_lock, flags);
1464
4670c46d 1465 ret = ocfs2_dlm_lock(osb->cconn, level, &lockres->l_lksb, lkm_flags,
24ef1815
JB		 1466 lockres->l_name, OCFS2_LOCK_ID_MAX_LEN - 1,
1467 lockres);
7431cd7e
JB		 1468 if (ret) {
1469 if (!trylock || (ret != -EAGAIN)) {
24ef1815 1470 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
cf8e06f1
MF		 1471 ret = -EINVAL;
1472 }
1473
1474 ocfs2_recover_from_dlm_error(lockres, 1);
1475 lockres_remove_mask_waiter(lockres, &mw);
1476 goto out;
1477 }
1478
1479 ret = ocfs2_wait_for_mask_interruptible(&mw, lockres);
1480 if (ret == -ERESTARTSYS) {
1481 /*
1482 * Userspace can cause deadlock itself with
1483 * flock(). Current behavior locally is to allow the
1484 * deadlock, but abort the system call if a signal is
1485 * received. We follow this example, otherwise a
1486 * poorly written program could sit in kernel until
1487 * reboot.
1488 *
1489 * Handling this is a bit more complicated for Ocfs2
1490 * though. We can't exit this function with an
1491 * outstanding lock request, so a cancel convert is
1492 * required. We intentionally overwrite 'ret' - if the
1493 * cancel fails and the lock was granted, it's easier
1494 * to just bubble sucess back up to the user.
1495 */
1496 ret = ocfs2_flock_handle_signal(lockres, level);
1497 }
1498
1499out:
1500
1501 mlog(0, "Lock: \"%s\" ex: %d, trylock: %d, returns: %d\n",
1502 lockres->l_name, ex, trylock, ret);
1503 return ret;
1504}
1505
1506void ocfs2_file_unlock(struct file *file)
1507{
1508 int ret;
1509 unsigned long flags;
1510 struct ocfs2_file_private *fp = file->private_data;
1511 struct ocfs2_lock_res *lockres = &fp->fp_flock;
1512 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
1513 struct ocfs2_mask_waiter mw;
1514
1515 ocfs2_init_mask_waiter(&mw);
1516
1517 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED))
1518 return;
1519
1520 if (lockres->l_level == LKM_NLMODE)
1521 return;
1522
1523 mlog(0, "Unlock: \"%s\" flags: 0x%lx, level: %d, act: %d\n",
1524 lockres->l_name, lockres->l_flags, lockres->l_level,
1525 lockres->l_action);
1526
1527 spin_lock_irqsave(&lockres->l_lock, flags);
1528 /*
1529 * Fake a blocking ast for the downconvert code.
1530 */
1531 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
bd3e7610 1532 lockres->l_blocking = DLM_LOCK_EX;
cf8e06f1
MF		 1533
1534 ocfs2_prepare_downconvert(lockres, LKM_NLMODE);
1535 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1536 spin_unlock_irqrestore(&lockres->l_lock, flags);
1537
1538 ret = ocfs2_downconvert_lock(osb, lockres, LKM_NLMODE, 0);
1539 if (ret) {
1540 mlog_errno(ret);
1541 return;
1542 }
1543
1544 ret = ocfs2_wait_for_mask(&mw);
1545 if (ret)
1546 mlog_errno(ret);
1547}
1548
34d024f8
MF		 1549static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
1550 struct ocfs2_lock_res *lockres)
ccd979bd
MF		 1551{
1552 int kick = 0;
1553
1554 mlog_entry_void();
1555
1556 /* If we know that another node is waiting on our lock, kick
34d024f8 1557 * the downconvert thread * pre-emptively when we reach a release
ccd979bd
MF		 1558 * condition. */
1559 if (lockres->l_flags & OCFS2_LOCK_BLOCKED) {
1560 switch(lockres->l_blocking) {
bd3e7610 1561 case DLM_LOCK_EX:
ccd979bd
MF		 1562 if (!lockres->l_ex_holders && !lockres->l_ro_holders)
1563 kick = 1;
1564 break;
bd3e7610 1565 case DLM_LOCK_PR:
ccd979bd
MF		 1566 if (!lockres->l_ex_holders)
1567 kick = 1;
1568 break;
1569 default:
1570 BUG();
1571 }
1572 }
1573
1574 if (kick)
34d024f8 1575 ocfs2_wake_downconvert_thread(osb);
ccd979bd
MF		 1576
1577 mlog_exit_void();
1578}
1579
ccd979bd
MF		 1580#define OCFS2_SEC_BITS 34
1581#define OCFS2_SEC_SHIFT (64 - 34)
1582#define OCFS2_NSEC_MASK ((1ULL << OCFS2_SEC_SHIFT) - 1)
1583
1584/* LVB only has room for 64 bits of time here so we pack it for
1585 * now. */
1586static u64 ocfs2_pack_timespec(struct timespec *spec)
1587{
1588 u64 res;
1589 u64 sec = spec->tv_sec;
1590 u32 nsec = spec->tv_nsec;
1591
1592 res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK);
1593
1594 return res;
1595}
1596
1597/* Call this with the lockres locked. I am reasonably sure we don't
1598 * need ip_lock in this function as anyone who would be changing those
e63aecb6 1599 * values is supposed to be blocked in ocfs2_inode_lock right now. */
ccd979bd
MF		 1600static void __ocfs2_stuff_meta_lvb(struct inode *inode)
1601{
1602 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1603 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd
MF		 1604 struct ocfs2_meta_lvb *lvb;
1605
1606 mlog_entry_void();
1607
8f2c9c1b 1608 lvb = (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd 1609
24c19ef4
MF		 1610 /*
1611 * Invalidate the LVB of a deleted inode - this way other
1612 * nodes are forced to go to disk and discover the new inode
1613 * status.
1614 */
1615 if (oi->ip_flags & OCFS2_INODE_DELETED) {
1616 lvb->lvb_version = 0;
1617 goto out;
1618 }
1619
4d3b83f7 1620 lvb->lvb_version = OCFS2_LVB_VERSION;
ccd979bd
MF		 1621 lvb->lvb_isize = cpu_to_be64(i_size_read(inode));
1622 lvb->lvb_iclusters = cpu_to_be32(oi->ip_clusters);
1623 lvb->lvb_iuid = cpu_to_be32(inode->i_uid);
1624 lvb->lvb_igid = cpu_to_be32(inode->i_gid);
1625 lvb->lvb_imode = cpu_to_be16(inode->i_mode);
1626 lvb->lvb_inlink = cpu_to_be16(inode->i_nlink);
1627 lvb->lvb_iatime_packed =
1628 cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime));
1629 lvb->lvb_ictime_packed =
1630 cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime));
1631 lvb->lvb_imtime_packed =
1632 cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime));
ca4d147e 1633 lvb->lvb_iattr = cpu_to_be32(oi->ip_attr);
15b1e36b 1634 lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features);
f9e2d82e 1635 lvb->lvb_igeneration = cpu_to_be32(inode->i_generation);
ccd979bd 1636
24c19ef4 1637out:
ccd979bd
MF		 1638 mlog_meta_lvb(0, lockres);
1639
1640 mlog_exit_void();
1641}
1642
1643static void ocfs2_unpack_timespec(struct timespec *spec,
1644 u64 packed_time)
1645{
1646 spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT;
1647 spec->tv_nsec = packed_time & OCFS2_NSEC_MASK;
1648}
1649
1650static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
1651{
1652 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1653 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd
MF		 1654 struct ocfs2_meta_lvb *lvb;
1655
1656 mlog_entry_void();
1657
1658 mlog_meta_lvb(0, lockres);
1659
8f2c9c1b 1660 lvb = (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd
MF		 1661
1662 /* We're safe here without the lockres lock... */
1663 spin_lock(&oi->ip_lock);
1664 oi->ip_clusters = be32_to_cpu(lvb->lvb_iclusters);
1665 i_size_write(inode, be64_to_cpu(lvb->lvb_isize));
1666
ca4d147e 1667 oi->ip_attr = be32_to_cpu(lvb->lvb_iattr);
15b1e36b 1668 oi->ip_dyn_features = be16_to_cpu(lvb->lvb_idynfeatures);
ca4d147e
HP		 1669 ocfs2_set_inode_flags(inode);
1670
ccd979bd
MF		 1671 /* fast-symlinks are a special case */
1672 if (S_ISLNK(inode->i_mode) && !oi->ip_clusters)
1673 inode->i_blocks = 0;
1674 else
8110b073 1675 inode->i_blocks = ocfs2_inode_sector_count(inode);
ccd979bd
MF		 1676
1677 inode->i_uid = be32_to_cpu(lvb->lvb_iuid);
1678 inode->i_gid = be32_to_cpu(lvb->lvb_igid);
1679 inode->i_mode = be16_to_cpu(lvb->lvb_imode);
1680 inode->i_nlink = be16_to_cpu(lvb->lvb_inlink);
1681 ocfs2_unpack_timespec(&inode->i_atime,
1682 be64_to_cpu(lvb->lvb_iatime_packed));
1683 ocfs2_unpack_timespec(&inode->i_mtime,
1684 be64_to_cpu(lvb->lvb_imtime_packed));
1685 ocfs2_unpack_timespec(&inode->i_ctime,
1686 be64_to_cpu(lvb->lvb_ictime_packed));
1687 spin_unlock(&oi->ip_lock);
1688
1689 mlog_exit_void();
1690}
1691
f9e2d82e
MF		 1692static inline int ocfs2_meta_lvb_is_trustable(struct inode *inode,
1693 struct ocfs2_lock_res *lockres)
ccd979bd 1694{
8f2c9c1b
JB		 1695 struct ocfs2_meta_lvb *lvb =
1696 (struct ocfs2_meta_lvb *)ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd 1697
f9e2d82e
MF		 1698 if (lvb->lvb_version == OCFS2_LVB_VERSION
1699 && be32_to_cpu(lvb->lvb_igeneration) == inode->i_generation)
ccd979bd
MF		 1700 return 1;
1701 return 0;
1702}
1703
1704/* Determine whether a lock resource needs to be refreshed, and
1705 * arbitrate who gets to refresh it.
1706 *
1707 * 0 means no refresh needed.
1708 *
1709 * > 0 means you need to refresh this and you MUST call
1710 * ocfs2_complete_lock_res_refresh afterwards. */
1711static int ocfs2_should_refresh_lock_res(struct ocfs2_lock_res *lockres)
1712{
1713 unsigned long flags;
1714 int status = 0;
1715
1716 mlog_entry_void();
1717
1718refresh_check:
1719 spin_lock_irqsave(&lockres->l_lock, flags);
1720 if (!(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH)) {
1721 spin_unlock_irqrestore(&lockres->l_lock, flags);
1722 goto bail;
1723 }
1724
1725 if (lockres->l_flags & OCFS2_LOCK_REFRESHING) {
1726 spin_unlock_irqrestore(&lockres->l_lock, flags);
1727
1728 ocfs2_wait_on_refreshing_lock(lockres);
1729 goto refresh_check;
1730 }
1731
1732 /* Ok, I'll be the one to refresh this lock. */
1733 lockres_or_flags(lockres, OCFS2_LOCK_REFRESHING);
1734 spin_unlock_irqrestore(&lockres->l_lock, flags);
1735
1736 status = 1;
1737bail:
1738 mlog_exit(status);
1739 return status;
1740}
1741
1742/* If status is non zero, I'll mark it as not being in refresh
1743 * anymroe, but i won't clear the needs refresh flag. */
1744static inline void ocfs2_complete_lock_res_refresh(struct ocfs2_lock_res *lockres,
1745 int status)
1746{
1747 unsigned long flags;
1748 mlog_entry_void();
1749
1750 spin_lock_irqsave(&lockres->l_lock, flags);
1751 lockres_clear_flags(lockres, OCFS2_LOCK_REFRESHING);
1752 if (!status)
1753 lockres_clear_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
1754 spin_unlock_irqrestore(&lockres->l_lock, flags);
1755
1756 wake_up(&lockres->l_event);
1757
1758 mlog_exit_void();
1759}
1760
1761/* may or may not return a bh if it went to disk. */
e63aecb6 1762static int ocfs2_inode_lock_update(struct inode *inode,
ccd979bd
MF		 1763 struct buffer_head **bh)
1764{
1765 int status = 0;
1766 struct ocfs2_inode_info *oi = OCFS2_I(inode);
e63aecb6 1767 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
ccd979bd 1768 struct ocfs2_dinode *fe;
c271c5c2 1769 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 1770
1771 mlog_entry_void();
1772
be9e986b
MF		 1773 if (ocfs2_mount_local(osb))
1774 goto bail;
1775
ccd979bd
MF		 1776 spin_lock(&oi->ip_lock);
1777 if (oi->ip_flags & OCFS2_INODE_DELETED) {
b0697053 1778 mlog(0, "Orphaned inode %llu was deleted while we "
ccd979bd 1779 "were waiting on a lock. ip_flags = 0x%x\n",
b0697053 1780 (unsigned long long)oi->ip_blkno, oi->ip_flags);
ccd979bd
MF		 1781 spin_unlock(&oi->ip_lock);
1782 status = -ENOENT;
1783 goto bail;
1784 }
1785 spin_unlock(&oi->ip_lock);
1786
be9e986b
MF		 1787 if (!ocfs2_should_refresh_lock_res(lockres))
1788 goto bail;
ccd979bd
MF		 1789
1790 /* This will discard any caching information we might have had
1791 * for the inode metadata. */
1792 ocfs2_metadata_cache_purge(inode);
1793
83418978
MF		 1794 ocfs2_extent_map_trunc(inode, 0);
1795
be9e986b 1796 if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {
b0697053
MF		 1797 mlog(0, "Trusting LVB on inode %llu\n",
1798 (unsigned long long)oi->ip_blkno);
ccd979bd
MF		 1799 ocfs2_refresh_inode_from_lvb(inode);
1800 } else {
1801 /* Boo, we have to go to disk. */
1802 /* read bh, cast, ocfs2_refresh_inode */
1803 status = ocfs2_read_block(OCFS2_SB(inode->i_sb), oi->ip_blkno,
1804 bh, OCFS2_BH_CACHED, inode);
1805 if (status < 0) {
1806 mlog_errno(status);
1807 goto bail_refresh;
1808 }
1809 fe = (struct ocfs2_dinode *) (*bh)->b_data;
1810
1811 /* This is a good chance to make sure we're not
1812 * locking an invalid object.
1813 *
1814 * We bug on a stale inode here because we checked
1815 * above whether it was wiped from disk. The wiping
1816 * node provides a guarantee that we receive that
1817 * message and can mark the inode before dropping any
1818 * locks associated with it. */
1819 if (!OCFS2_IS_VALID_DINODE(fe)) {
1820 OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
1821 status = -EIO;
1822 goto bail_refresh;
1823 }
1824 mlog_bug_on_msg(inode->i_generation !=
1825 le32_to_cpu(fe->i_generation),
b0697053 1826 "Invalid dinode %llu disk generation: %u "
ccd979bd 1827 "inode->i_generation: %u\n",
b0697053
MF		 1828 (unsigned long long)oi->ip_blkno,
1829 le32_to_cpu(fe->i_generation),
ccd979bd
MF		 1830 inode->i_generation);
1831 mlog_bug_on_msg(le64_to_cpu(fe->i_dtime) ||
1832 !(fe->i_flags & cpu_to_le32(OCFS2_VALID_FL)),
b0697053
MF		 1833 "Stale dinode %llu dtime: %llu flags: 0x%x\n",
1834 (unsigned long long)oi->ip_blkno,
1835 (unsigned long long)le64_to_cpu(fe->i_dtime),
ccd979bd
MF		 1836 le32_to_cpu(fe->i_flags));
1837
1838 ocfs2_refresh_inode(inode, fe);
1839 }
1840
1841 status = 0;
1842bail_refresh:
be9e986b 1843 ocfs2_complete_lock_res_refresh(lockres, status);
ccd979bd
MF		 1844bail:
1845 mlog_exit(status);
1846 return status;
1847}
1848
1849static int ocfs2_assign_bh(struct inode *inode,
1850 struct buffer_head **ret_bh,
1851 struct buffer_head *passed_bh)
1852{
1853 int status;
1854
1855 if (passed_bh) {
1856 /* Ok, the update went to disk for us, use the
1857 * returned bh. */
1858 *ret_bh = passed_bh;
1859 get_bh(*ret_bh);
1860
1861 return 0;
1862 }
1863
1864 status = ocfs2_read_block(OCFS2_SB(inode->i_sb),
1865 OCFS2_I(inode)->ip_blkno,
1866 ret_bh,
1867 OCFS2_BH_CACHED,
1868 inode);
1869 if (status < 0)
1870 mlog_errno(status);
1871
1872 return status;
1873}
1874
1875/*
1876 * returns < 0 error if the callback will never be called, otherwise
1877 * the result of the lock will be communicated via the callback.
1878 */
e63aecb6 1879int ocfs2_inode_lock_full(struct inode *inode,
ccd979bd
MF		 1880 struct buffer_head **ret_bh,
1881 int ex,
1882 int arg_flags)
1883{
bd3e7610
JB		 1884 int status, level, acquired;
1885 u32 dlm_flags;
c271c5c2 1886 struct ocfs2_lock_res *lockres = NULL;
ccd979bd
MF		 1887 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1888 struct buffer_head *local_bh = NULL;
1889
1890 BUG_ON(!inode);
1891
1892 mlog_entry_void();
1893
b0697053
MF		 1894 mlog(0, "inode %llu, take %s META lock\n",
1895 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 1896 ex ? "EXMODE" : "PRMODE");
1897
1898 status = 0;
1899 acquired = 0;
1900 /* We'll allow faking a readonly metadata lock for
1901 * rodevices. */
1902 if (ocfs2_is_hard_readonly(osb)) {
1903 if (ex)
1904 status = -EROFS;
1905 goto bail;
1906 }
1907
c271c5c2
SM		 1908 if (ocfs2_mount_local(osb))
1909 goto local;
1910
ccd979bd 1911 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
553abd04 1912 ocfs2_wait_for_recovery(osb);
ccd979bd 1913
e63aecb6 1914 lockres = &OCFS2_I(inode)->ip_inode_lockres;
bd3e7610 1915 level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 1916 dlm_flags = 0;
1917 if (arg_flags & OCFS2_META_LOCK_NOQUEUE)
bd3e7610 1918 dlm_flags |= DLM_LKF_NOQUEUE;
ccd979bd
MF		 1919
1920 status = ocfs2_cluster_lock(osb, lockres, level, dlm_flags, arg_flags);
1921 if (status < 0) {
1922 if (status != -EAGAIN && status != -EIOCBRETRY)
1923 mlog_errno(status);
1924 goto bail;
1925 }
1926
1927 /* Notify the error cleanup path to drop the cluster lock. */
1928 acquired = 1;
1929
1930 /* We wait twice because a node may have died while we were in
1931 * the lower dlm layers. The second time though, we've
1932 * committed to owning this lock so we don't allow signals to
1933 * abort the operation. */
1934 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
553abd04 1935 ocfs2_wait_for_recovery(osb);
ccd979bd 1936
c271c5c2 1937local:
24c19ef4
MF		 1938 /*
1939 * We only see this flag if we're being called from
1940 * ocfs2_read_locked_inode(). It means we're locking an inode
1941 * which hasn't been populated yet, so clear the refresh flag
1942 * and let the caller handle it.
1943 */
1944 if (inode->i_state & I_NEW) {
1945 status = 0;
c271c5c2
SM		 1946 if (lockres)
1947 ocfs2_complete_lock_res_refresh(lockres, 0);
24c19ef4
MF		 1948 goto bail;
1949 }
1950
ccd979bd 1951 /* This is fun. The caller may want a bh back, or it may
e63aecb6 1952 * not. ocfs2_inode_lock_update definitely wants one in, but
ccd979bd
MF		 1953 * may or may not read one, depending on what's in the
1954 * LVB. The result of all of this is that we've *only* gone to
1955 * disk if we have to, so the complexity is worthwhile. */
e63aecb6 1956 status = ocfs2_inode_lock_update(inode, &local_bh);
ccd979bd
MF		 1957 if (status < 0) {
1958 if (status != -ENOENT)
1959 mlog_errno(status);
1960 goto bail;
1961 }
1962
1963 if (ret_bh) {
1964 status = ocfs2_assign_bh(inode, ret_bh, local_bh);
1965 if (status < 0) {
1966 mlog_errno(status);
1967 goto bail;
1968 }
1969 }
1970
ccd979bd
MF		 1971bail:
1972 if (status < 0) {
1973 if (ret_bh && (*ret_bh)) {
1974 brelse(*ret_bh);
1975 *ret_bh = NULL;
1976 }
1977 if (acquired)
e63aecb6 1978 ocfs2_inode_unlock(inode, ex);
ccd979bd
MF		 1979 }
1980
1981 if (local_bh)
1982 brelse(local_bh);
1983
1984 mlog_exit(status);
1985 return status;
1986}
1987
1988/*
34d024f8
MF		 1989 * This is working around a lock inversion between tasks acquiring DLM
1990 * locks while holding a page lock and the downconvert thread which
1991 * blocks dlm lock acquiry while acquiring page locks.
ccd979bd
MF		 1992 *
1993 * ** These _with_page variantes are only intended to be called from aop
1994 * methods that hold page locks and return a very specific *positive* error
1995 * code that aop methods pass up to the VFS -- test for errors with != 0. **
1996 *
34d024f8
MF		 1997 * The DLM is called such that it returns -EAGAIN if it would have
1998 * blocked waiting for the downconvert thread. In that case we unlock
1999 * our page so the downconvert thread can make progress. Once we've
2000 * done this we have to return AOP_TRUNCATED_PAGE so the aop method
2001 * that called us can bubble that back up into the VFS who will then
2002 * immediately retry the aop call.
ccd979bd
MF		 2003 *
2004 * We do a blocking lock and immediate unlock before returning, though, so that
2005 * the lock has a great chance of being cached on this node by the time the VFS
2006 * calls back to retry the aop. This has a potential to livelock as nodes
2007 * ping locks back and forth, but that's a risk we're willing to take to avoid
2008 * the lock inversion simply.
2009 */
e63aecb6 2010int ocfs2_inode_lock_with_page(struct inode *inode,
ccd979bd
MF		 2011 struct buffer_head **ret_bh,
2012 int ex,
2013 struct page *page)
2014{
2015 int ret;
2016
e63aecb6 2017 ret = ocfs2_inode_lock_full(inode, ret_bh, ex, OCFS2_LOCK_NONBLOCK);
ccd979bd
MF		 2018 if (ret == -EAGAIN) {
2019 unlock_page(page);
e63aecb6
MF		 2020 if (ocfs2_inode_lock(inode, ret_bh, ex) == 0)
2021 ocfs2_inode_unlock(inode, ex);
ccd979bd
MF		 2022 ret = AOP_TRUNCATED_PAGE;
2023 }
2024
2025 return ret;
2026}
2027
e63aecb6 2028int ocfs2_inode_lock_atime(struct inode *inode,
7f1a37e3
TY		 2029 struct vfsmount *vfsmnt,
2030 int *level)
2031{
2032 int ret;
2033
2034 mlog_entry_void();
e63aecb6 2035 ret = ocfs2_inode_lock(inode, NULL, 0);
7f1a37e3
TY		 2036 if (ret < 0) {
2037 mlog_errno(ret);
2038 return ret;
2039 }
2040
2041 /*
2042 * If we should update atime, we will get EX lock,
2043 * otherwise we just get PR lock.
2044 */
2045 if (ocfs2_should_update_atime(inode, vfsmnt)) {
2046 struct buffer_head *bh = NULL;
2047
e63aecb6
MF		 2048 ocfs2_inode_unlock(inode, 0);
2049 ret = ocfs2_inode_lock(inode, &bh, 1);
7f1a37e3
TY		 2050 if (ret < 0) {
2051 mlog_errno(ret);
2052 return ret;
2053 }
2054 *level = 1;
2055 if (ocfs2_should_update_atime(inode, vfsmnt))
2056 ocfs2_update_inode_atime(inode, bh);
2057 if (bh)
2058 brelse(bh);
2059 } else
2060 *level = 0;
2061
2062 mlog_exit(ret);
2063 return ret;
2064}
2065
e63aecb6 2066void ocfs2_inode_unlock(struct inode *inode,
ccd979bd
MF		 2067 int ex)
2068{
bd3e7610 2069 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
e63aecb6 2070 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_inode_lockres;
c271c5c2 2071 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ccd979bd
MF		 2072
2073 mlog_entry_void();
2074
b0697053
MF		 2075 mlog(0, "inode %llu drop %s META lock\n",
2076 (unsigned long long)OCFS2_I(inode)->ip_blkno,
ccd979bd
MF		 2077 ex ? "EXMODE" : "PRMODE");
2078
c271c5c2
SM		 2079 if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)) &&
2080 !ocfs2_mount_local(osb))
ccd979bd
MF		 2081 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
2082
2083 mlog_exit_void();
2084}
2085
2086int ocfs2_super_lock(struct ocfs2_super *osb,
2087 int ex)
2088{
c271c5c2 2089 int status = 0;
bd3e7610 2090 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd 2091 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
ccd979bd
MF		 2092
2093 mlog_entry_void();
2094
2095 if (ocfs2_is_hard_readonly(osb))
2096 return -EROFS;
2097
c271c5c2
SM		 2098 if (ocfs2_mount_local(osb))
2099 goto bail;
2100
ccd979bd
MF		 2101 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
2102 if (status < 0) {
2103 mlog_errno(status);
2104 goto bail;
2105 }
2106
2107 /* The super block lock path is really in the best position to
2108 * know when resources covered by the lock need to be
2109 * refreshed, so we do it here. Of course, making sense of
2110 * everything is up to the caller :) */
2111 status = ocfs2_should_refresh_lock_res(lockres);
2112 if (status < 0) {
2113 mlog_errno(status);
2114 goto bail;
2115 }
2116 if (status) {
8e8a4603 2117 status = ocfs2_refresh_slot_info(osb);
ccd979bd
MF		 2118
2119 ocfs2_complete_lock_res_refresh(lockres, status);
2120
2121 if (status < 0)
2122 mlog_errno(status);
2123 }
2124bail:
2125 mlog_exit(status);
2126 return status;
2127}
2128
2129void ocfs2_super_unlock(struct ocfs2_super *osb,
2130 int ex)
2131{
bd3e7610 2132 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
ccd979bd
MF		 2133 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
2134
c271c5c2
SM		 2135 if (!ocfs2_mount_local(osb))
2136 ocfs2_cluster_unlock(osb, lockres, level);
ccd979bd
MF		 2137}
2138
2139int ocfs2_rename_lock(struct ocfs2_super *osb)
2140{
2141 int status;
2142 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2143
2144 if (ocfs2_is_hard_readonly(osb))
2145 return -EROFS;
2146
c271c5c2
SM		 2147 if (ocfs2_mount_local(osb))
2148 return 0;
2149
bd3e7610 2150 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_EX, 0, 0);
ccd979bd
MF		 2151 if (status < 0)
2152 mlog_errno(status);
2153
2154 return status;
2155}
2156
2157void ocfs2_rename_unlock(struct ocfs2_super *osb)
2158{
2159 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2160
c271c5c2 2161 if (!ocfs2_mount_local(osb))
bd3e7610 2162 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
ccd979bd
MF		 2163}
2164
d680efe9
MF		 2165int ocfs2_dentry_lock(struct dentry *dentry, int ex)
2166{
2167 int ret;
bd3e7610 2168 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
d680efe9
MF		 2169 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2170 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2171
2172 BUG_ON(!dl);
2173
2174 if (ocfs2_is_hard_readonly(osb))
2175 return -EROFS;
2176
c271c5c2
SM		 2177 if (ocfs2_mount_local(osb))
2178 return 0;
2179
d680efe9
MF		 2180 ret = ocfs2_cluster_lock(osb, &dl->dl_lockres, level, 0, 0);
2181 if (ret < 0)
2182 mlog_errno(ret);
2183
2184 return ret;
2185}
2186
2187void ocfs2_dentry_unlock(struct dentry *dentry, int ex)
2188{
bd3e7610 2189 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
d680efe9
MF		 2190 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2191 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2192
c271c5c2
SM		 2193 if (!ocfs2_mount_local(osb))
2194 ocfs2_cluster_unlock(osb, &dl->dl_lockres, level);
d680efe9
MF		 2195}
2196
ccd979bd
MF		 2197/* Reference counting of the dlm debug structure. We want this because
2198 * open references on the debug inodes can live on after a mount, so
2199 * we can't rely on the ocfs2_super to always exist. */
2200static void ocfs2_dlm_debug_free(struct kref *kref)
2201{
2202 struct ocfs2_dlm_debug *dlm_debug;
2203
2204 dlm_debug = container_of(kref, struct ocfs2_dlm_debug, d_refcnt);
2205
2206 kfree(dlm_debug);
2207}
2208
2209void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug)
2210{
2211 if (dlm_debug)
2212 kref_put(&dlm_debug->d_refcnt, ocfs2_dlm_debug_free);
2213}
2214
2215static void ocfs2_get_dlm_debug(struct ocfs2_dlm_debug *debug)
2216{
2217 kref_get(&debug->d_refcnt);
2218}
2219
2220struct ocfs2_dlm_debug *ocfs2_new_dlm_debug(void)
2221{
2222 struct ocfs2_dlm_debug *dlm_debug;
2223
2224 dlm_debug = kmalloc(sizeof(struct ocfs2_dlm_debug), GFP_KERNEL);
2225 if (!dlm_debug) {
2226 mlog_errno(-ENOMEM);
2227 goto out;
2228 }
2229
2230 kref_init(&dlm_debug->d_refcnt);
2231 INIT_LIST_HEAD(&dlm_debug->d_lockres_tracking);
2232 dlm_debug->d_locking_state = NULL;
2233out:
2234 return dlm_debug;
2235}
2236
2237/* Access to this is arbitrated for us via seq_file->sem. */
2238struct ocfs2_dlm_seq_priv {
2239 struct ocfs2_dlm_debug *p_dlm_debug;
2240 struct ocfs2_lock_res p_iter_res;
2241 struct ocfs2_lock_res p_tmp_res;
2242};
2243
2244static struct ocfs2_lock_res *ocfs2_dlm_next_res(struct ocfs2_lock_res *start,
2245 struct ocfs2_dlm_seq_priv *priv)
2246{
2247 struct ocfs2_lock_res *iter, *ret = NULL;
2248 struct ocfs2_dlm_debug *dlm_debug = priv->p_dlm_debug;
2249
2250 assert_spin_locked(&ocfs2_dlm_tracking_lock);
2251
2252 list_for_each_entry(iter, &start->l_debug_list, l_debug_list) {
2253 /* discover the head of the list */
2254 if (&iter->l_debug_list == &dlm_debug->d_lockres_tracking) {
2255 mlog(0, "End of list found, %p\n", ret);
2256 break;
2257 }
2258
2259 /* We track our "dummy" iteration lockres' by a NULL
2260 * l_ops field. */
2261 if (iter->l_ops != NULL) {
2262 ret = iter;
2263 break;
2264 }
2265 }
2266
2267 return ret;
2268}
2269
2270static void *ocfs2_dlm_seq_start(struct seq_file *m, loff_t *pos)
2271{
2272 struct ocfs2_dlm_seq_priv *priv = m->private;
2273 struct ocfs2_lock_res *iter;
2274
2275 spin_lock(&ocfs2_dlm_tracking_lock);
2276 iter = ocfs2_dlm_next_res(&priv->p_iter_res, priv);
2277 if (iter) {
2278 /* Since lockres' have the lifetime of their container
2279 * (which can be inodes, ocfs2_supers, etc) we want to
2280 * copy this out to a temporary lockres while still
2281 * under the spinlock. Obviously after this we can't
2282 * trust any pointers on the copy returned, but that's
2283 * ok as the information we want isn't typically held
2284 * in them. */
2285 priv->p_tmp_res = *iter;
2286 iter = &priv->p_tmp_res;
2287 }
2288 spin_unlock(&ocfs2_dlm_tracking_lock);
2289
2290 return iter;
2291}
2292
2293static void ocfs2_dlm_seq_stop(struct seq_file *m, void *v)
2294{
2295}
2296
2297static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
2298{
2299 struct ocfs2_dlm_seq_priv *priv = m->private;
2300 struct ocfs2_lock_res *iter = v;
2301 struct ocfs2_lock_res *dummy = &priv->p_iter_res;
2302
2303 spin_lock(&ocfs2_dlm_tracking_lock);
2304 iter = ocfs2_dlm_next_res(iter, priv);
2305 list_del_init(&dummy->l_debug_list);
2306 if (iter) {
2307 list_add(&dummy->l_debug_list, &iter->l_debug_list);
2308 priv->p_tmp_res = *iter;
2309 iter = &priv->p_tmp_res;
2310 }
2311 spin_unlock(&ocfs2_dlm_tracking_lock);
2312
2313 return iter;
2314}
2315
2316/* So that debugfs.ocfs2 can determine which format is being used */
2317#define OCFS2_DLM_DEBUG_STR_VERSION 1
2318static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
2319{
2320 int i;
2321 char *lvb;
2322 struct ocfs2_lock_res *lockres = v;
2323
2324 if (!lockres)
2325 return -EINVAL;
2326
d680efe9
MF		 2327 seq_printf(m, "0x%x\t", OCFS2_DLM_DEBUG_STR_VERSION);
2328
2329 if (lockres->l_type == OCFS2_LOCK_TYPE_DENTRY)
2330 seq_printf(m, "%.*s%08x\t", OCFS2_DENTRY_LOCK_INO_START - 1,
2331 lockres->l_name,
2332 (unsigned int)ocfs2_get_dentry_lock_ino(lockres));
2333 else
2334 seq_printf(m, "%.*s\t", OCFS2_LOCK_ID_MAX_LEN, lockres->l_name);
2335
2336 seq_printf(m, "%d\t"
ccd979bd
MF		 2337 "0x%lx\t"
2338 "0x%x\t"
2339 "0x%x\t"
2340 "%u\t"
2341 "%u\t"
2342 "%d\t"
2343 "%d\t",
ccd979bd
MF		 2344 lockres->l_level,
2345 lockres->l_flags,
2346 lockres->l_action,
2347 lockres->l_unlock_action,
2348 lockres->l_ro_holders,
2349 lockres->l_ex_holders,
2350 lockres->l_requested,
2351 lockres->l_blocking);
2352
2353 /* Dump the raw LVB */
8f2c9c1b 2354 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
ccd979bd
MF		 2355 for(i = 0; i < DLM_LVB_LEN; i++)
2356 seq_printf(m, "0x%x\t", lvb[i]);
2357
2358 /* End the line */
2359 seq_printf(m, "\n");
2360 return 0;
2361}
2362
90d99779 2363static const struct seq_operations ocfs2_dlm_seq_ops = {
ccd979bd
MF		 2364 .start = ocfs2_dlm_seq_start,
2365 .stop = ocfs2_dlm_seq_stop,
2366 .next = ocfs2_dlm_seq_next,
2367 .show = ocfs2_dlm_seq_show,
2368};
2369
2370static int ocfs2_dlm_debug_release(struct inode *inode, struct file *file)
2371{
2372 struct seq_file *seq = (struct seq_file *) file->private_data;
2373 struct ocfs2_dlm_seq_priv *priv = seq->private;
2374 struct ocfs2_lock_res *res = &priv->p_iter_res;
2375
2376 ocfs2_remove_lockres_tracking(res);
2377 ocfs2_put_dlm_debug(priv->p_dlm_debug);
2378 return seq_release_private(inode, file);
2379}
2380
2381static int ocfs2_dlm_debug_open(struct inode *inode, struct file *file)
2382{
2383 int ret;
2384 struct ocfs2_dlm_seq_priv *priv;
2385 struct seq_file *seq;
2386 struct ocfs2_super *osb;
2387
2388 priv = kzalloc(sizeof(struct ocfs2_dlm_seq_priv), GFP_KERNEL);
2389 if (!priv) {
2390 ret = -ENOMEM;
2391 mlog_errno(ret);
2392 goto out;
2393 }
8e18e294 2394 osb = inode->i_private;
ccd979bd
MF		 2395 ocfs2_get_dlm_debug(osb->osb_dlm_debug);
2396 priv->p_dlm_debug = osb->osb_dlm_debug;
2397 INIT_LIST_HEAD(&priv->p_iter_res.l_debug_list);
2398
2399 ret = seq_open(file, &ocfs2_dlm_seq_ops);
2400 if (ret) {
2401 kfree(priv);
2402 mlog_errno(ret);
2403 goto out;
2404 }
2405
2406 seq = (struct seq_file *) file->private_data;
2407 seq->private = priv;
2408
2409 ocfs2_add_lockres_tracking(&priv->p_iter_res,
2410 priv->p_dlm_debug);
2411
2412out:
2413 return ret;
2414}
2415
4b6f5d20 2416static const struct file_operations ocfs2_dlm_debug_fops = {
ccd979bd
MF		 2417 .open = ocfs2_dlm_debug_open,
2418 .release = ocfs2_dlm_debug_release,
2419 .read = seq_read,
2420 .llseek = seq_lseek,
2421};
2422
2423static int ocfs2_dlm_init_debug(struct ocfs2_super *osb)
2424{
2425 int ret = 0;
2426 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
2427
2428 dlm_debug->d_locking_state = debugfs_create_file("locking_state",
2429 S_IFREG|S_IRUSR,
2430 osb->osb_debug_root,
2431 osb,
2432 &ocfs2_dlm_debug_fops);
2433 if (!dlm_debug->d_locking_state) {
2434 ret = -EINVAL;
2435 mlog(ML_ERROR,
2436 "Unable to create locking state debugfs file.\n");
2437 goto out;
2438 }
2439
2440 ocfs2_get_dlm_debug(dlm_debug);
2441out:
2442 return ret;
2443}
2444
2445static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)
2446{
2447 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
2448
2449 if (dlm_debug) {
2450 debugfs_remove(dlm_debug->d_locking_state);
2451 ocfs2_put_dlm_debug(dlm_debug);
2452 }
2453}
2454
2455int ocfs2_dlm_init(struct ocfs2_super *osb)
2456{
c271c5c2 2457 int status = 0;
4670c46d 2458 struct ocfs2_cluster_connection *conn = NULL;
ccd979bd
MF		 2459
2460 mlog_entry_void();
2461
c271c5c2
SM		 2462 if (ocfs2_mount_local(osb))
2463 goto local;
2464
ccd979bd
MF		 2465 status = ocfs2_dlm_init_debug(osb);
2466 if (status < 0) {
2467 mlog_errno(status);
2468 goto bail;
2469 }
2470
34d024f8
MF		 2471 /* launch downconvert thread */
2472 osb->dc_task = kthread_run(ocfs2_downconvert_thread, osb, "ocfs2dc");
2473 if (IS_ERR(osb->dc_task)) {
2474 status = PTR_ERR(osb->dc_task);
2475 osb->dc_task = NULL;
ccd979bd
MF		 2476 mlog_errno(status);
2477 goto bail;
2478 }
2479
ccd979bd 2480 /* for now, uuid == domain */
4670c46d
JB		 2481 status = ocfs2_cluster_connect(osb->uuid_str,
2482 strlen(osb->uuid_str),
2483 ocfs2_do_node_down, osb,
2484 &conn);
2485 if (status) {
ccd979bd
MF		 2486 mlog_errno(status);
2487 goto bail;
2488 }
2489
c271c5c2 2490local:
ccd979bd
MF		 2491 ocfs2_super_lock_res_init(&osb->osb_super_lockres, osb);
2492 ocfs2_rename_lock_res_init(&osb->osb_rename_lockres, osb);
2493
4670c46d 2494 osb->cconn = conn;
ccd979bd
MF		 2495
2496 status = 0;
2497bail:
2498 if (status < 0) {
2499 ocfs2_dlm_shutdown_debug(osb);
34d024f8
MF		 2500 if (osb->dc_task)
2501 kthread_stop(osb->dc_task);
ccd979bd
MF		 2502 }
2503
2504 mlog_exit(status);
2505 return status;
2506}
2507
2508void ocfs2_dlm_shutdown(struct ocfs2_super *osb)
2509{
2510 mlog_entry_void();
2511
ccd979bd
MF		 2512 ocfs2_drop_osb_locks(osb);
2513
4670c46d
JB		 2514 /*
2515 * Now that we have dropped all locks and ocfs2_dismount_volume()
2516 * has disabled recovery, the DLM won't be talking to us. It's
2517 * safe to tear things down before disconnecting the cluster.
2518 */
2519
34d024f8
MF		 2520 if (osb->dc_task) {
2521 kthread_stop(osb->dc_task);
2522 osb->dc_task = NULL;
ccd979bd
MF		 2523 }
2524
2525 ocfs2_lock_res_free(&osb->osb_super_lockres);
2526 ocfs2_lock_res_free(&osb->osb_rename_lockres);
2527
4670c46d
JB		 2528 ocfs2_cluster_disconnect(osb->cconn);
2529 osb->cconn = NULL;
ccd979bd
MF		 2530
2531 ocfs2_dlm_shutdown_debug(osb);
2532
2533 mlog_exit_void();
2534}
2535
7431cd7e 2536static void ocfs2_unlock_ast(void *opaque, int error)
ccd979bd
MF		 2537{
2538 struct ocfs2_lock_res *lockres = opaque;
2539 unsigned long flags;
2540
2541 mlog_entry_void();
2542
2543 mlog(0, "UNLOCK AST called on lock %s, action = %d\n", lockres->l_name,
2544 lockres->l_unlock_action);
2545
2546 spin_lock_irqsave(&lockres->l_lock, flags);
2547 /* We tried to cancel a convert request, but it was already
2548 * granted. All we want to do here is clear our unlock
2549 * state. The wake_up call done at the bottom is redundant
2550 * (ocfs2_prepare_cancel_convert doesn't sleep on this) but doesn't
2551 * hurt anything anyway */
7431cd7e 2552 if (error == -DLM_ECANCEL &&
ccd979bd
MF		 2553 lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT) {
2554 mlog(0, "Got cancelgrant for %s\n", lockres->l_name);
2555
2556 /* We don't clear the busy flag in this case as it
2557 * should have been cleared by the ast which the dlm
2558 * has called. */
2559 goto complete_unlock;
2560 }
2561
7431cd7e
JB		 2562 /* DLM_EUNLOCK is the success code for unlock */
2563 if (error != -DLM_EUNLOCK) {
2564 mlog(ML_ERROR, "Dlm passes error %d for lock %s, "
2565 "unlock_action %d\n", error, lockres->l_name,
ccd979bd
MF		 2566 lockres->l_unlock_action);
2567 spin_unlock_irqrestore(&lockres->l_lock, flags);
2568 return;
2569 }
2570
2571 switch(lockres->l_unlock_action) {
2572 case OCFS2_UNLOCK_CANCEL_CONVERT:
2573 mlog(0, "Cancel convert success for %s\n", lockres->l_name);
2574 lockres->l_action = OCFS2_AST_INVALID;
2575 break;
2576 case OCFS2_UNLOCK_DROP_LOCK:
bd3e7610 2577 lockres->l_level = DLM_LOCK_IV;
ccd979bd
MF		 2578 break;
2579 default:
2580 BUG();
2581 }
2582
2583 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
2584complete_unlock:
2585 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
2586 spin_unlock_irqrestore(&lockres->l_lock, flags);
2587
2588 wake_up(&lockres->l_event);
2589
2590 mlog_exit_void();
2591}
2592
ccd979bd 2593static int ocfs2_drop_lock(struct ocfs2_super *osb,
0d5dc6c2 2594 struct ocfs2_lock_res *lockres)
ccd979bd 2595{
7431cd7e 2596 int ret;
ccd979bd 2597 unsigned long flags;
bd3e7610 2598 u32 lkm_flags = 0;
ccd979bd
MF		 2599
2600 /* We didn't get anywhere near actually using this lockres. */
2601 if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED))
2602 goto out;
2603
b80fc012 2604 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
bd3e7610 2605 lkm_flags |= DLM_LKF_VALBLK;
b80fc012 2606
ccd979bd
MF		 2607 spin_lock_irqsave(&lockres->l_lock, flags);
2608
2609 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_FREEING),
2610 "lockres %s, flags 0x%lx\n",
2611 lockres->l_name, lockres->l_flags);
2612
2613 while (lockres->l_flags & OCFS2_LOCK_BUSY) {
2614 mlog(0, "waiting on busy lock \"%s\": flags = %lx, action = "
2615 "%u, unlock_action = %u\n",
2616 lockres->l_name, lockres->l_flags, lockres->l_action,
2617 lockres->l_unlock_action);
2618
2619 spin_unlock_irqrestore(&lockres->l_lock, flags);
2620
2621 /* XXX: Today we just wait on any busy
2622 * locks... Perhaps we need to cancel converts in the
2623 * future? */
2624 ocfs2_wait_on_busy_lock(lockres);
2625
2626 spin_lock_irqsave(&lockres->l_lock, flags);
2627 }
2628
0d5dc6c2
MF		 2629 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
2630 if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
bd3e7610 2631 lockres->l_level == DLM_LOCK_EX &&
0d5dc6c2
MF		 2632 !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
2633 lockres->l_ops->set_lvb(lockres);
2634 }
ccd979bd
MF		 2635
2636 if (lockres->l_flags & OCFS2_LOCK_BUSY)
2637 mlog(ML_ERROR, "destroying busy lock: \"%s\"\n",
2638 lockres->l_name);
2639 if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
2640 mlog(0, "destroying blocked lock: \"%s\"\n", lockres->l_name);
2641
2642 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
2643 spin_unlock_irqrestore(&lockres->l_lock, flags);
2644 goto out;
2645 }
2646
2647 lockres_clear_flags(lockres, OCFS2_LOCK_ATTACHED);
2648
2649 /* make sure we never get here while waiting for an ast to
2650 * fire. */
2651 BUG_ON(lockres->l_action != OCFS2_AST_INVALID);
2652
2653 /* is this necessary? */
2654 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
2655 lockres->l_unlock_action = OCFS2_UNLOCK_DROP_LOCK;
2656 spin_unlock_irqrestore(&lockres->l_lock, flags);
2657
2658 mlog(0, "lock %s\n", lockres->l_name);
2659
4670c46d 2660 ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb, lkm_flags,
7431cd7e
JB		 2661 lockres);
2662 if (ret) {
2663 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
ccd979bd 2664 mlog(ML_ERROR, "lockres flags: %lu\n", lockres->l_flags);
8f2c9c1b
JB		 2665 /* XXX Need to abstract this */
2666 dlm_print_one_lock(lockres->l_lksb.lksb_o2dlm.lockid);
ccd979bd
MF		 2667 BUG();
2668 }
24ef1815 2669 mlog(0, "lock %s, successfull return from ocfs2_dlm_unlock\n",
ccd979bd
MF		 2670 lockres->l_name);
2671
2672 ocfs2_wait_on_busy_lock(lockres);
2673out:
2674 mlog_exit(0);
2675 return 0;
2676}
2677
2678/* Mark the lockres as being dropped. It will no longer be
2679 * queued if blocking, but we still may have to wait on it
34d024f8 2680 * being dequeued from the downconvert thread before we can consider
ccd979bd
MF		 2681 * it safe to drop.
2682 *
2683 * You can *not* attempt to call cluster_lock on this lockres anymore. */
2684void ocfs2_mark_lockres_freeing(struct ocfs2_lock_res *lockres)
2685{
2686 int status;
2687 struct ocfs2_mask_waiter mw;
2688 unsigned long flags;
2689
2690 ocfs2_init_mask_waiter(&mw);
2691
2692 spin_lock_irqsave(&lockres->l_lock, flags);
2693 lockres->l_flags |= OCFS2_LOCK_FREEING;
2694 while (lockres->l_flags & OCFS2_LOCK_QUEUED) {
2695 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_QUEUED, 0);
2696 spin_unlock_irqrestore(&lockres->l_lock, flags);
2697
2698 mlog(0, "Waiting on lockres %s\n", lockres->l_name);
2699
2700 status = ocfs2_wait_for_mask(&mw);
2701 if (status)
2702 mlog_errno(status);
2703
2704 spin_lock_irqsave(&lockres->l_lock, flags);
2705 }
2706 spin_unlock_irqrestore(&lockres->l_lock, flags);
2707}
2708
d680efe9
MF		 2709void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
2710 struct ocfs2_lock_res *lockres)
ccd979bd 2711{
d680efe9 2712 int ret;
ccd979bd 2713
d680efe9 2714 ocfs2_mark_lockres_freeing(lockres);
0d5dc6c2 2715 ret = ocfs2_drop_lock(osb, lockres);
d680efe9
MF		 2716 if (ret)
2717 mlog_errno(ret);
2718}
ccd979bd 2719
d680efe9
MF		 2720static void ocfs2_drop_osb_locks(struct ocfs2_super *osb)
2721{
2722 ocfs2_simple_drop_lockres(osb, &osb->osb_super_lockres);
2723 ocfs2_simple_drop_lockres(osb, &osb->osb_rename_lockres);
ccd979bd
MF		 2724}
2725
ccd979bd
MF		 2726int ocfs2_drop_inode_locks(struct inode *inode)
2727{
2728 int status, err;
ccd979bd
MF		 2729
2730 mlog_entry_void();
2731
2732 /* No need to call ocfs2_mark_lockres_freeing here -
2733 * ocfs2_clear_inode has done it for us. */
2734
2735 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
50008630 2736 &OCFS2_I(inode)->ip_open_lockres);
ccd979bd
MF		 2737 if (err < 0)
2738 mlog_errno(err);
2739
2740 status = err;
2741
2742 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
e63aecb6 2743 &OCFS2_I(inode)->ip_inode_lockres);
ccd979bd
MF		 2744 if (err < 0)
2745 mlog_errno(err);
2746 if (err < 0 && !status)
2747 status = err;
2748
2749 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
0d5dc6c2 2750 &OCFS2_I(inode)->ip_rw_lockres);
ccd979bd
MF		 2751 if (err < 0)
2752 mlog_errno(err);
2753 if (err < 0 && !status)
2754 status = err;
2755
2756 mlog_exit(status);
2757 return status;
2758}
2759
2760static void ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
2761 int new_level)
2762{
2763 assert_spin_locked(&lockres->l_lock);
2764
bd3e7610 2765 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
ccd979bd
MF		 2766
2767 if (lockres->l_level <= new_level) {
bd3e7610 2768 mlog(ML_ERROR, "lockres->l_level (%d) <= new_level (%d)\n",
ccd979bd
MF		 2769 lockres->l_level, new_level);
2770 BUG();
2771 }
2772
2773 mlog(0, "lock %s, new_level = %d, l_blocking = %d\n",
2774 lockres->l_name, new_level, lockres->l_blocking);
2775
2776 lockres->l_action = OCFS2_AST_DOWNCONVERT;
2777 lockres->l_requested = new_level;
2778 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
2779}
2780
2781static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
2782 struct ocfs2_lock_res *lockres,
2783 int new_level,
2784 int lvb)
2785{
bd3e7610
JB		 2786 int ret;
2787 u32 dlm_flags = DLM_LKF_CONVERT;
ccd979bd
MF		 2788
2789 mlog_entry_void();
2790
2791 if (lvb)
bd3e7610 2792 dlm_flags |= DLM_LKF_VALBLK;
ccd979bd 2793
4670c46d 2794 ret = ocfs2_dlm_lock(osb->cconn,
7431cd7e
JB		 2795 new_level,
2796 &lockres->l_lksb,
2797 dlm_flags,
2798 lockres->l_name,
2799 OCFS2_LOCK_ID_MAX_LEN - 1,
2800 lockres);
2801 if (ret) {
2802 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
ccd979bd
MF		 2803 ocfs2_recover_from_dlm_error(lockres, 1);
2804 goto bail;
2805 }
2806
2807 ret = 0;
2808bail:
2809 mlog_exit(ret);
2810 return ret;
2811}
2812
24ef1815 2813/* returns 1 when the caller should unlock and call ocfs2_dlm_unlock */
ccd979bd
MF		 2814static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
2815 struct ocfs2_lock_res *lockres)
2816{
2817 assert_spin_locked(&lockres->l_lock);
2818
2819 mlog_entry_void();
2820 mlog(0, "lock %s\n", lockres->l_name);
2821
2822 if (lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT) {
2823 /* If we're already trying to cancel a lock conversion
2824 * then just drop the spinlock and allow the caller to
2825 * requeue this lock. */
2826
2827 mlog(0, "Lockres %s, skip convert\n", lockres->l_name);
2828 return 0;
2829 }
2830
2831 /* were we in a convert when we got the bast fire? */
2832 BUG_ON(lockres->l_action != OCFS2_AST_CONVERT &&
2833 lockres->l_action != OCFS2_AST_DOWNCONVERT);
2834 /* set things up for the unlockast to know to just
2835 * clear out the ast_action and unset busy, etc. */
2836 lockres->l_unlock_action = OCFS2_UNLOCK_CANCEL_CONVERT;
2837
2838 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_BUSY),
2839 "lock %s, invalid flags: 0x%lx\n",
2840 lockres->l_name, lockres->l_flags);
2841
2842 return 1;
2843}
2844
2845static int ocfs2_cancel_convert(struct ocfs2_super *osb,
2846 struct ocfs2_lock_res *lockres)
2847{
2848 int ret;
ccd979bd
MF		 2849
2850 mlog_entry_void();
2851 mlog(0, "lock %s\n", lockres->l_name);
2852
4670c46d 2853 ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb,
7431cd7e
JB		 2854 DLM_LKF_CANCEL, lockres);
2855 if (ret) {
2856 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
ccd979bd
MF		 2857 ocfs2_recover_from_dlm_error(lockres, 0);
2858 }
2859
24ef1815 2860 mlog(0, "lock %s return from ocfs2_dlm_unlock\n", lockres->l_name);
ccd979bd 2861
ccd979bd
MF		 2862 mlog_exit(ret);
2863 return ret;
2864}
2865
b5e500e2
MF		 2866static int ocfs2_unblock_lock(struct ocfs2_super *osb,
2867 struct ocfs2_lock_res *lockres,
2868 struct ocfs2_unblock_ctl *ctl)
ccd979bd
MF		 2869{
2870 unsigned long flags;
2871 int blocking;
2872 int new_level;
2873 int ret = 0;
5ef0d4ea 2874 int set_lvb = 0;
ccd979bd
MF		 2875
2876 mlog_entry_void();
2877
2878 spin_lock_irqsave(&lockres->l_lock, flags);
2879
2880 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
2881
2882recheck:
2883 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
d680efe9 2884 ctl->requeue = 1;
ccd979bd
MF		 2885 ret = ocfs2_prepare_cancel_convert(osb, lockres);
2886 spin_unlock_irqrestore(&lockres->l_lock, flags);
2887 if (ret) {
2888 ret = ocfs2_cancel_convert(osb, lockres);
2889 if (ret < 0)
2890 mlog_errno(ret);
2891 }
2892 goto leave;
2893 }
2894
2895 /* if we're blocking an exclusive and we have *any* holders,
2896 * then requeue. */
bd3e7610 2897 if ((lockres->l_blocking == DLM_LOCK_EX)
f7fbfdd1
MF		 2898 && (lockres->l_ex_holders || lockres->l_ro_holders))
2899 goto leave_requeue;
ccd979bd
MF		 2900
2901 /* If it's a PR we're blocking, then only
2902 * requeue if we've got any EX holders */
bd3e7610 2903 if (lockres->l_blocking == DLM_LOCK_PR &&
f7fbfdd1
MF		 2904 lockres->l_ex_holders)
2905 goto leave_requeue;
2906
2907 /*
2908 * Can we get a lock in this state if the holder counts are
2909 * zero? The meta data unblock code used to check this.
2910 */
2911 if ((lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
2912 && (lockres->l_flags & OCFS2_LOCK_REFRESHING))
2913 goto leave_requeue;
ccd979bd 2914
16d5b956
MF		 2915 new_level = ocfs2_highest_compat_lock_level(lockres->l_blocking);
2916
2917 if (lockres->l_ops->check_downconvert
2918 && !lockres->l_ops->check_downconvert(lockres, new_level))
2919 goto leave_requeue;
2920
ccd979bd
MF		 2921 /* If we get here, then we know that there are no more
2922 * incompatible holders (and anyone asking for an incompatible
2923 * lock is blocked). We can now downconvert the lock */
cc567d89 2924 if (!lockres->l_ops->downconvert_worker)
ccd979bd
MF		 2925 goto downconvert;
2926
2927 /* Some lockres types want to do a bit of work before
2928 * downconverting a lock. Allow that here. The worker function
2929 * may sleep, so we save off a copy of what we're blocking as
2930 * it may change while we're not holding the spin lock. */
2931 blocking = lockres->l_blocking;
2932 spin_unlock_irqrestore(&lockres->l_lock, flags);
2933
cc567d89 2934 ctl->unblock_action = lockres->l_ops->downconvert_worker(lockres, blocking);
d680efe9
MF		 2935
2936 if (ctl->unblock_action == UNBLOCK_STOP_POST)
2937 goto leave;
ccd979bd
MF		 2938
2939 spin_lock_irqsave(&lockres->l_lock, flags);
2940 if (blocking != lockres->l_blocking) {
2941 /* If this changed underneath us, then we can't drop
2942 * it just yet. */
2943 goto recheck;
2944 }
2945
2946downconvert:
d680efe9 2947 ctl->requeue = 0;
ccd979bd 2948
5ef0d4ea 2949 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
bd3e7610 2950 if (lockres->l_level == DLM_LOCK_EX)
5ef0d4ea
MF		 2951 set_lvb = 1;
2952
2953 /*
2954 * We only set the lvb if the lock has been fully
2955 * refreshed - otherwise we risk setting stale
2956 * data. Otherwise, there's no need to actually clear
2957 * out the lvb here as it's value is still valid.
2958 */
2959 if (set_lvb && !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
2960 lockres->l_ops->set_lvb(lockres);
2961 }
2962
ccd979bd
MF		 2963 ocfs2_prepare_downconvert(lockres, new_level);
2964 spin_unlock_irqrestore(&lockres->l_lock, flags);
5ef0d4ea 2965 ret = ocfs2_downconvert_lock(osb, lockres, new_level, set_lvb);
ccd979bd
MF		 2966leave:
2967 mlog_exit(ret);
2968 return ret;
f7fbfdd1
MF		 2969
2970leave_requeue:
2971 spin_unlock_irqrestore(&lockres->l_lock, flags);
2972 ctl->requeue = 1;
2973
2974 mlog_exit(0);
2975 return 0;
ccd979bd
MF		 2976}
2977
d680efe9
MF		 2978static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
2979 int blocking)
ccd979bd
MF		 2980{
2981 struct inode *inode;
2982 struct address_space *mapping;
2983
ccd979bd
MF		 2984 inode = ocfs2_lock_res_inode(lockres);
2985 mapping = inode->i_mapping;
2986
1044e401 2987 if (!S_ISREG(inode->i_mode))
f1f54068
MF		 2988 goto out;
2989
7f4a2a97
MF		 2990 /*
2991 * We need this before the filemap_fdatawrite() so that it can
2992 * transfer the dirty bit from the PTE to the
2993 * page. Unfortunately this means that even for EX->PR
2994 * downconverts, we'll lose our mappings and have to build
2995 * them up again.
2996 */
2997 unmap_mapping_range(mapping, 0, 0, 0);
2998
ccd979bd 2999 if (filemap_fdatawrite(mapping)) {
b0697053
MF		 3000 mlog(ML_ERROR, "Could not sync inode %llu for downconvert!",
3001 (unsigned long long)OCFS2_I(inode)->ip_blkno);
ccd979bd
MF		 3002 }
3003 sync_mapping_buffers(mapping);
bd3e7610 3004 if (blocking == DLM_LOCK_EX) {
ccd979bd 3005 truncate_inode_pages(mapping, 0);
ccd979bd
MF		 3006 } else {
3007 /* We only need to wait on the I/O if we're not also
3008 * truncating pages because truncate_inode_pages waits
3009 * for us above. We don't truncate pages if we're
3010 * blocking anything < EXMODE because we want to keep
3011 * them around in that case. */
3012 filemap_fdatawait(mapping);
3013 }
3014
f1f54068 3015out:
d680efe9 3016 return UNBLOCK_CONTINUE;
ccd979bd
MF		 3017}
3018
810d5aeb
MF		 3019static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
3020 int new_level)
3021{
3022 struct inode *inode = ocfs2_lock_res_inode(lockres);
3023 int checkpointed = ocfs2_inode_fully_checkpointed(inode);
3024
bd3e7610
JB		 3025 BUG_ON(new_level != DLM_LOCK_NL && new_level != DLM_LOCK_PR);
3026 BUG_ON(lockres->l_level != DLM_LOCK_EX && !checkpointed);
810d5aeb
MF		 3027
3028 if (checkpointed)
3029 return 1;
3030
3031 ocfs2_start_checkpoint(OCFS2_SB(inode->i_sb));
3032 return 0;
3033}
3034
3035static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres)
3036{
3037 struct inode *inode = ocfs2_lock_res_inode(lockres);
3038
3039 __ocfs2_stuff_meta_lvb(inode);
3040}
3041
d680efe9
MF		 3042/*
3043 * Does the final reference drop on our dentry lock. Right now this
34d024f8 3044 * happens in the downconvert thread, but we could choose to simplify the
d680efe9
MF		 3045 * dlmglue API and push these off to the ocfs2_wq in the future.
3046 */
3047static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
3048 struct ocfs2_lock_res *lockres)
3049{
3050 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
3051 ocfs2_dentry_lock_put(osb, dl);
3052}
3053
3054/*
3055 * d_delete() matching dentries before the lock downconvert.
3056 *
3057 * At this point, any process waiting to destroy the
3058 * dentry_lock due to last ref count is stopped by the
3059 * OCFS2_LOCK_QUEUED flag.
3060 *
3061 * We have two potential problems
3062 *
3063 * 1) If we do the last reference drop on our dentry_lock (via dput)
3064 * we'll wind up in ocfs2_release_dentry_lock(), waiting on
3065 * the downconvert to finish. Instead we take an elevated
3066 * reference and push the drop until after we've completed our
3067 * unblock processing.
3068 *
3069 * 2) There might be another process with a final reference,
3070 * waiting on us to finish processing. If this is the case, we
3071 * detect it and exit out - there's no more dentries anyway.
3072 */
3073static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
3074 int blocking)
3075{
3076 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
3077 struct ocfs2_inode_info *oi = OCFS2_I(dl->dl_inode);
3078 struct dentry *dentry;
3079 unsigned long flags;
3080 int extra_ref = 0;
3081
3082 /*
3083 * This node is blocking another node from getting a read
3084 * lock. This happens when we've renamed within a
3085 * directory. We've forced the other nodes to d_delete(), but
3086 * we never actually dropped our lock because it's still
3087 * valid. The downconvert code will retain a PR for this node,
3088 * so there's no further work to do.
3089 */
bd3e7610 3090 if (blocking == DLM_LOCK_PR)
d680efe9
MF		 3091 return UNBLOCK_CONTINUE;
3092
3093 /*
3094 * Mark this inode as potentially orphaned. The code in
3095 * ocfs2_delete_inode() will figure out whether it actually
3096 * needs to be freed or not.
3097 */
3098 spin_lock(&oi->ip_lock);
3099 oi->ip_flags |= OCFS2_INODE_MAYBE_ORPHANED;
3100 spin_unlock(&oi->ip_lock);
3101
3102 /*
3103 * Yuck. We need to make sure however that the check of
3104 * OCFS2_LOCK_FREEING and the extra reference are atomic with
3105 * respect to a reference decrement or the setting of that
3106 * flag.
3107 */
3108 spin_lock_irqsave(&lockres->l_lock, flags);
3109 spin_lock(&dentry_attach_lock);
3110 if (!(lockres->l_flags & OCFS2_LOCK_FREEING)
3111 && dl->dl_count) {
3112 dl->dl_count++;
3113 extra_ref = 1;
3114 }
3115 spin_unlock(&dentry_attach_lock);
3116 spin_unlock_irqrestore(&lockres->l_lock, flags);
3117
3118 mlog(0, "extra_ref = %d\n", extra_ref);
3119
3120 /*
3121 * We have a process waiting on us in ocfs2_dentry_iput(),
3122 * which means we can't have any more outstanding
3123 * aliases. There's no need to do any more work.
3124 */
3125 if (!extra_ref)
3126 return UNBLOCK_CONTINUE;
3127
3128 spin_lock(&dentry_attach_lock);
3129 while (1) {
3130 dentry = ocfs2_find_local_alias(dl->dl_inode,
3131 dl->dl_parent_blkno, 1);
3132 if (!dentry)
3133 break;
3134 spin_unlock(&dentry_attach_lock);
3135
3136 mlog(0, "d_delete(%.*s);\n", dentry->d_name.len,
3137 dentry->d_name.name);
3138
3139 /*
3140 * The following dcache calls may do an
3141 * iput(). Normally we don't want that from the
3142 * downconverting thread, but in this case it's ok
3143 * because the requesting node already has an
3144 * exclusive lock on the inode, so it can't be queued
3145 * for a downconvert.
3146 */
3147 d_delete(dentry);
3148 dput(dentry);
3149
3150 spin_lock(&dentry_attach_lock);
3151 }
3152 spin_unlock(&dentry_attach_lock);
3153
3154 /*
3155 * If we are the last holder of this dentry lock, there is no
3156 * reason to downconvert so skip straight to the unlock.
3157 */
3158 if (dl->dl_count == 1)
3159 return UNBLOCK_STOP_POST;
3160
3161 return UNBLOCK_CONTINUE_POST;
3162}
3163
4670c46d
JB		 3164/*
3165 * This is the filesystem locking protocol. It provides the lock handling
3166 * hooks for the underlying DLM. It has a maximum version number.
3167 * The version number allows interoperability with systems running at
3168 * the same major number and an equal or smaller minor number.
3169 *
3170 * Whenever the filesystem does new things with locks (adds or removes a
3171 * lock, orders them differently, does different things underneath a lock),
3172 * the version must be changed. The protocol is negotiated when joining
3173 * the dlm domain. A node may join the domain if its major version is
3174 * identical to all other nodes and its minor version is greater than
3175 * or equal to all other nodes. When its minor version is greater than
3176 * the other nodes, it will run at the minor version specified by the
3177 * other nodes.
3178 *
3179 * If a locking change is made that will not be compatible with older
3180 * versions, the major number must be increased and the minor version set
3181 * to zero. If a change merely adds a behavior that can be disabled when
3182 * speaking to older versions, the minor version must be increased. If a
3183 * change adds a fully backwards compatible change (eg, LVB changes that
3184 * are just ignored by older versions), the version does not need to be
3185 * updated.
3186 */
24ef1815 3187static struct ocfs2_locking_protocol lproto = {
4670c46d
JB		 3188 .lp_max_version = {
3189 .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
3190 .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
3191 },
24ef1815
JB		 3192 .lp_lock_ast = ocfs2_locking_ast,
3193 .lp_blocking_ast = ocfs2_blocking_ast,
3194 .lp_unlock_ast = ocfs2_unlock_ast,
3195};
3196
3197/* This interface isn't the final one, hence the less-than-perfect names */
3198void dlmglue_init_stack(void)
3199{
3200 o2cb_get_stack(&lproto);
3201}
3202
3203void dlmglue_exit_stack(void)
3204{
3205 o2cb_put_stack();
3206}
3207
00600056
AB		 3208static void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
3209 struct ocfs2_lock_res *lockres)
ccd979bd
MF		 3210{
3211 int status;
d680efe9 3212 struct ocfs2_unblock_ctl ctl = {0, 0,};
ccd979bd
MF		 3213 unsigned long flags;
3214
3215 /* Our reference to the lockres in this function can be
3216 * considered valid until we remove the OCFS2_LOCK_QUEUED
3217 * flag. */
3218
3219 mlog_entry_void();
3220
3221 BUG_ON(!lockres);
3222 BUG_ON(!lockres->l_ops);
ccd979bd
MF		 3223
3224 mlog(0, "lockres %s blocked.\n", lockres->l_name);
3225
3226 /* Detect whether a lock has been marked as going away while
34d024f8 3227 * the downconvert thread was processing other things. A lock can
ccd979bd
MF		 3228 * still be marked with OCFS2_LOCK_FREEING after this check,
3229 * but short circuiting here will still save us some
3230 * performance. */
3231 spin_lock_irqsave(&lockres->l_lock, flags);
3232 if (lockres->l_flags & OCFS2_LOCK_FREEING)
3233 goto unqueue;
3234 spin_unlock_irqrestore(&lockres->l_lock, flags);
3235
b5e500e2 3236 status = ocfs2_unblock_lock(osb, lockres, &ctl);
ccd979bd
MF		 3237 if (status < 0)
3238 mlog_errno(status);
3239
3240 spin_lock_irqsave(&lockres->l_lock, flags);
3241unqueue:
d680efe9 3242 if (lockres->l_flags & OCFS2_LOCK_FREEING || !ctl.requeue) {
ccd979bd
MF		 3243 lockres_clear_flags(lockres, OCFS2_LOCK_QUEUED);
3244 } else
3245 ocfs2_schedule_blocked_lock(osb, lockres);
3246
3247 mlog(0, "lockres %s, requeue = %s.\n", lockres->l_name,
d680efe9 3248 ctl.requeue ? "yes" : "no");
ccd979bd
MF		 3249 spin_unlock_irqrestore(&lockres->l_lock, flags);
3250
d680efe9
MF		 3251 if (ctl.unblock_action != UNBLOCK_CONTINUE
3252 && lockres->l_ops->post_unlock)
3253 lockres->l_ops->post_unlock(osb, lockres);
3254
ccd979bd
MF		 3255 mlog_exit_void();
3256}
3257
3258static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
3259 struct ocfs2_lock_res *lockres)
3260{
3261 mlog_entry_void();
3262
3263 assert_spin_locked(&lockres->l_lock);
3264
3265 if (lockres->l_flags & OCFS2_LOCK_FREEING) {
3266 /* Do not schedule a lock for downconvert when it's on
3267 * the way to destruction - any nodes wanting access
3268 * to the resource will get it soon. */
3269 mlog(0, "Lockres %s won't be scheduled: flags 0x%lx\n",
3270 lockres->l_name, lockres->l_flags);
3271 return;
3272 }
3273
3274 lockres_or_flags(lockres, OCFS2_LOCK_QUEUED);
3275
34d024f8 3276 spin_lock(&osb->dc_task_lock);
ccd979bd
MF		 3277 if (list_empty(&lockres->l_blocked_list)) {
3278 list_add_tail(&lockres->l_blocked_list,
3279 &osb->blocked_lock_list);
3280 osb->blocked_lock_count++;
3281 }
34d024f8 3282 spin_unlock(&osb->dc_task_lock);
ccd979bd
MF		 3283
3284 mlog_exit_void();
3285}
34d024f8
MF		 3286
3287static void ocfs2_downconvert_thread_do_work(struct ocfs2_super *osb)
3288{
3289 unsigned long processed;
3290 struct ocfs2_lock_res *lockres;
3291
3292 mlog_entry_void();
3293
3294 spin_lock(&osb->dc_task_lock);
3295 /* grab this early so we know to try again if a state change and
3296 * wake happens part-way through our work */
3297 osb->dc_work_sequence = osb->dc_wake_sequence;
3298
3299 processed = osb->blocked_lock_count;
3300 while (processed) {
3301 BUG_ON(list_empty(&osb->blocked_lock_list));
3302
3303 lockres = list_entry(osb->blocked_lock_list.next,
3304 struct ocfs2_lock_res, l_blocked_list);
3305 list_del_init(&lockres->l_blocked_list);
3306 osb->blocked_lock_count--;
3307 spin_unlock(&osb->dc_task_lock);
3308
3309 BUG_ON(!processed);
3310 processed--;
3311
3312 ocfs2_process_blocked_lock(osb, lockres);
3313
3314 spin_lock(&osb->dc_task_lock);
3315 }
3316 spin_unlock(&osb->dc_task_lock);
3317
3318 mlog_exit_void();
3319}
3320
3321static int ocfs2_downconvert_thread_lists_empty(struct ocfs2_super *osb)
3322{
3323 int empty = 0;
3324
3325 spin_lock(&osb->dc_task_lock);
3326 if (list_empty(&osb->blocked_lock_list))
3327 empty = 1;
3328
3329 spin_unlock(&osb->dc_task_lock);
3330 return empty;
3331}
3332
3333static int ocfs2_downconvert_thread_should_wake(struct ocfs2_super *osb)
3334{
3335 int should_wake = 0;
3336
3337 spin_lock(&osb->dc_task_lock);
3338 if (osb->dc_work_sequence != osb->dc_wake_sequence)
3339 should_wake = 1;
3340 spin_unlock(&osb->dc_task_lock);
3341
3342 return should_wake;
3343}
3344
200bfae3 3345static int ocfs2_downconvert_thread(void *arg)
34d024f8
MF		 3346{
3347 int status = 0;
3348 struct ocfs2_super *osb = arg;
3349
3350 /* only quit once we've been asked to stop and there is no more
3351 * work available */
3352 while (!(kthread_should_stop() &&
3353 ocfs2_downconvert_thread_lists_empty(osb))) {
3354
3355 wait_event_interruptible(osb->dc_event,
3356 ocfs2_downconvert_thread_should_wake(osb) ||
3357 kthread_should_stop());
3358
3359 mlog(0, "downconvert_thread: awoken\n");
3360
3361 ocfs2_downconvert_thread_do_work(osb);
3362 }
3363
3364 osb->dc_task = NULL;
3365 return status;
3366}
3367
3368void ocfs2_wake_downconvert_thread(struct ocfs2_super *osb)
3369{
3370 spin_lock(&osb->dc_task_lock);
3371 /* make sure the voting thread gets a swipe at whatever changes
3372 * the caller may have made to the voting state */
3373 osb->dc_wake_sequence++;
3374 spin_unlock(&osb->dc_task_lock);
3375 wake_up(&osb->dc_event);
3376}
kernel source for telekom puls (alcatel/mediatek)