1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- mode: c; c-basic-offset: 8; -*-
3 * vim: noexpandtab sw=8 ts=8 sts=0:
7 * Code which implements an OCFS2 specific interface to our DLM.
9 * Copyright (C) 2003, 2004 Oracle. All rights reserved.
12 #include <linux/types.h>
13 #include <linux/slab.h>
14 #include <linux/highmem.h>
16 #include <linux/kthread.h>
17 #include <linux/pagemap.h>
18 #include <linux/debugfs.h>
19 #include <linux/seq_file.h>
20 #include <linux/time.h>
21 #include <linux/quotaops.h>
22 #include <linux/sched/signal.h>
24 #define MLOG_MASK_PREFIX ML_DLM_GLUE
25 #include <cluster/masklog.h>
28 #include "ocfs2_lockingver.h"
33 #include "extent_map.h"
35 #include "heartbeat.h"
38 #include "stackglue.h"
43 #include "refcounttree.h"
46 #include "buffer_head_io.h"
48 struct ocfs2_mask_waiter {
49 struct list_head mw_item;
51 struct completion mw_complete;
52 unsigned long mw_mask;
53 unsigned long mw_goal;
54 #ifdef CONFIG_OCFS2_FS_STATS
55 ktime_t mw_lock_start;
59 static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres);
60 static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres);
61 static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres);
62 static struct ocfs2_super *ocfs2_get_qinfo_osb(struct ocfs2_lock_res *lockres);
65 * Return value from ->downconvert_worker functions.
67 * These control the precise actions of ocfs2_unblock_lock()
68 * and ocfs2_process_blocked_lock()
71 enum ocfs2_unblock_action {
72 UNBLOCK_CONTINUE = 0, /* Continue downconvert */
73 UNBLOCK_CONTINUE_POST = 1, /* Continue downconvert, fire
74 * ->post_unlock callback */
75 UNBLOCK_STOP_POST = 2, /* Do not downconvert, fire
76 * ->post_unlock() callback. */
79 struct ocfs2_unblock_ctl {
81 enum ocfs2_unblock_action unblock_action;
84 /* Lockdep class keys */
85 #ifdef CONFIG_DEBUG_LOCK_ALLOC
86 static struct lock_class_key lockdep_keys[OCFS2_NUM_LOCK_TYPES];
89 static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
91 static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres);
93 static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
96 static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
99 static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
100 struct ocfs2_lock_res *lockres);
102 static void ocfs2_set_qinfo_lvb(struct ocfs2_lock_res *lockres);
104 static int ocfs2_check_refcount_downconvert(struct ocfs2_lock_res *lockres,
106 static int ocfs2_refcount_convert_worker(struct ocfs2_lock_res *lockres,
109 #define mlog_meta_lvb(__level, __lockres) ocfs2_dump_meta_lvb_info(__level, __PRETTY_FUNCTION__, __LINE__, __lockres)
111 /* This aids in debugging situations where a bad LVB might be involved. */
112 static void ocfs2_dump_meta_lvb_info(u64 level,
113 const char *function,
115 struct ocfs2_lock_res *lockres)
117 struct ocfs2_meta_lvb *lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
119 mlog(level, "LVB information for %s (called from %s:%u):\n",
120 lockres->l_name, function, line);
121 mlog(level, "version: %u, clusters: %u, generation: 0x%x\n",
122 lvb->lvb_version, be32_to_cpu(lvb->lvb_iclusters),
123 be32_to_cpu(lvb->lvb_igeneration));
124 mlog(level, "size: %llu, uid %u, gid %u, mode 0x%x\n",
125 (unsigned long long)be64_to_cpu(lvb->lvb_isize),
126 be32_to_cpu(lvb->lvb_iuid), be32_to_cpu(lvb->lvb_igid),
127 be16_to_cpu(lvb->lvb_imode));
128 mlog(level, "nlink %u, atime_packed 0x%llx, ctime_packed 0x%llx, "
129 "mtime_packed 0x%llx iattr 0x%x\n", be16_to_cpu(lvb->lvb_inlink),
130 (long long)be64_to_cpu(lvb->lvb_iatime_packed),
131 (long long)be64_to_cpu(lvb->lvb_ictime_packed),
132 (long long)be64_to_cpu(lvb->lvb_imtime_packed),
133 be32_to_cpu(lvb->lvb_iattr));
138 * OCFS2 Lock Resource Operations
140 * These fine tune the behavior of the generic dlmglue locking infrastructure.
142 * The most basic of lock types can point ->l_priv to their respective
143 * struct ocfs2_super and allow the default actions to manage things.
145 * Right now, each lock type also needs to implement an init function,
146 * and trivial lock/unlock wrappers. ocfs2_simple_drop_lockres()
147 * should be called when the lock is no longer needed (i.e., object
150 struct ocfs2_lock_res_ops {
152 * Translate an ocfs2_lock_res * into an ocfs2_super *. Define
153 * this callback if ->l_priv is not an ocfs2_super pointer
155 struct ocfs2_super * (*get_osb)(struct ocfs2_lock_res *);
158 * Optionally called in the downconvert thread after a
159 * successful downconvert. The lockres will not be referenced
160 * after this callback is called, so it is safe to free
163 * The exact semantics of when this is called are controlled
164 * by ->downconvert_worker()
166 void (*post_unlock)(struct ocfs2_super *, struct ocfs2_lock_res *);
169 * Allow a lock type to add checks to determine whether it is
170 * safe to downconvert a lock. Return 0 to re-queue the
171 * downconvert at a later time, nonzero to continue.
173 * For most locks, the default checks that there are no
174 * incompatible holders are sufficient.
176 * Called with the lockres spinlock held.
178 int (*check_downconvert)(struct ocfs2_lock_res *, int);
181 * Allows a lock type to populate the lock value block. This
182 * is called on downconvert, and when we drop a lock.
184 * Locks that want to use this should set LOCK_TYPE_USES_LVB
185 * in the flags field.
187 * Called with the lockres spinlock held.
189 void (*set_lvb)(struct ocfs2_lock_res *);
192 * Called from the downconvert thread when it is determined
193 * that a lock will be downconverted. This is called without
194 * any locks held so the function can do work that might
195 * schedule (syncing out data, etc).
197 * This should return any one of the ocfs2_unblock_action
198 * values, depending on what it wants the thread to do.
200 int (*downconvert_worker)(struct ocfs2_lock_res *, int);
203 * LOCK_TYPE_* flags which describe the specific requirements
204 * of a lock type. Descriptions of each individual flag follow.
210 * Some locks want to "refresh" potentially stale data when a
211 * meaningful (PRMODE or EXMODE) lock level is first obtained. If this
212 * flag is set, the OCFS2_LOCK_NEEDS_REFRESH flag will be set on the
213 * individual lockres l_flags member from the ast function. It is
214 * expected that the locking wrapper will clear the
215 * OCFS2_LOCK_NEEDS_REFRESH flag when done.
217 #define LOCK_TYPE_REQUIRES_REFRESH 0x1
220 * Indicate that a lock type makes use of the lock value block. The
221 * ->set_lvb lock type callback must be defined.
223 #define LOCK_TYPE_USES_LVB 0x2
225 static struct ocfs2_lock_res_ops ocfs2_inode_rw_lops = {
226 .get_osb = ocfs2_get_inode_osb,
230 static struct ocfs2_lock_res_ops ocfs2_inode_inode_lops = {
231 .get_osb = ocfs2_get_inode_osb,
232 .check_downconvert = ocfs2_check_meta_downconvert,
233 .set_lvb = ocfs2_set_meta_lvb,
234 .downconvert_worker = ocfs2_data_convert_worker,
235 .flags = LOCK_TYPE_REQUIRES_REFRESH|LOCK_TYPE_USES_LVB,
238 static struct ocfs2_lock_res_ops ocfs2_super_lops = {
239 .flags = LOCK_TYPE_REQUIRES_REFRESH,
242 static struct ocfs2_lock_res_ops ocfs2_rename_lops = {
246 static struct ocfs2_lock_res_ops ocfs2_nfs_sync_lops = {
250 static struct ocfs2_lock_res_ops ocfs2_trim_fs_lops = {
251 .flags = LOCK_TYPE_REQUIRES_REFRESH|LOCK_TYPE_USES_LVB,
254 static struct ocfs2_lock_res_ops ocfs2_orphan_scan_lops = {
255 .flags = LOCK_TYPE_REQUIRES_REFRESH|LOCK_TYPE_USES_LVB,
258 static struct ocfs2_lock_res_ops ocfs2_dentry_lops = {
259 .get_osb = ocfs2_get_dentry_osb,
260 .post_unlock = ocfs2_dentry_post_unlock,
261 .downconvert_worker = ocfs2_dentry_convert_worker,
265 static struct ocfs2_lock_res_ops ocfs2_inode_open_lops = {
266 .get_osb = ocfs2_get_inode_osb,
270 static struct ocfs2_lock_res_ops ocfs2_flock_lops = {
271 .get_osb = ocfs2_get_file_osb,
275 static struct ocfs2_lock_res_ops ocfs2_qinfo_lops = {
276 .set_lvb = ocfs2_set_qinfo_lvb,
277 .get_osb = ocfs2_get_qinfo_osb,
278 .flags = LOCK_TYPE_REQUIRES_REFRESH | LOCK_TYPE_USES_LVB,
281 static struct ocfs2_lock_res_ops ocfs2_refcount_block_lops = {
282 .check_downconvert = ocfs2_check_refcount_downconvert,
283 .downconvert_worker = ocfs2_refcount_convert_worker,
287 static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
289 return lockres->l_type == OCFS2_LOCK_TYPE_META ||
290 lockres->l_type == OCFS2_LOCK_TYPE_RW ||
291 lockres->l_type == OCFS2_LOCK_TYPE_OPEN;
294 static inline struct ocfs2_lock_res *ocfs2_lksb_to_lock_res(struct ocfs2_dlm_lksb *lksb)
296 return container_of(lksb, struct ocfs2_lock_res, l_lksb);
299 static inline struct inode *ocfs2_lock_res_inode(struct ocfs2_lock_res *lockres)
301 BUG_ON(!ocfs2_is_inode_lock(lockres));
303 return (struct inode *) lockres->l_priv;
306 static inline struct ocfs2_dentry_lock *ocfs2_lock_res_dl(struct ocfs2_lock_res *lockres)
308 BUG_ON(lockres->l_type != OCFS2_LOCK_TYPE_DENTRY);
310 return (struct ocfs2_dentry_lock *)lockres->l_priv;
313 static inline struct ocfs2_mem_dqinfo *ocfs2_lock_res_qinfo(struct ocfs2_lock_res *lockres)
315 BUG_ON(lockres->l_type != OCFS2_LOCK_TYPE_QINFO);
317 return (struct ocfs2_mem_dqinfo *)lockres->l_priv;
320 static inline struct ocfs2_refcount_tree *
321 ocfs2_lock_res_refcount_tree(struct ocfs2_lock_res *res)
323 return container_of(res, struct ocfs2_refcount_tree, rf_lockres);
326 static inline struct ocfs2_super *ocfs2_get_lockres_osb(struct ocfs2_lock_res *lockres)
328 if (lockres->l_ops->get_osb)
329 return lockres->l_ops->get_osb(lockres);
331 return (struct ocfs2_super *)lockres->l_priv;
334 static int ocfs2_lock_create(struct ocfs2_super *osb,
335 struct ocfs2_lock_res *lockres,
338 static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
340 static void __ocfs2_cluster_unlock(struct ocfs2_super *osb,
341 struct ocfs2_lock_res *lockres,
342 int level, unsigned long caller_ip);
343 static inline void ocfs2_cluster_unlock(struct ocfs2_super *osb,
344 struct ocfs2_lock_res *lockres,
347 __ocfs2_cluster_unlock(osb, lockres, level, _RET_IP_);
350 static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres);
351 static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres);
352 static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres);
353 static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres, int level);
354 static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
355 struct ocfs2_lock_res *lockres);
356 static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
358 #define ocfs2_log_dlm_error(_func, _err, _lockres) do { \
359 if ((_lockres)->l_type != OCFS2_LOCK_TYPE_DENTRY) \
360 mlog(ML_ERROR, "DLM error %d while calling %s on resource %s\n", \
361 _err, _func, _lockres->l_name); \
363 mlog(ML_ERROR, "DLM error %d while calling %s on resource %.*s%08x\n", \
364 _err, _func, OCFS2_DENTRY_LOCK_INO_START - 1, (_lockres)->l_name, \
365 (unsigned int)ocfs2_get_dentry_lock_ino(_lockres)); \
367 static int ocfs2_downconvert_thread(void *arg);
368 static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
369 struct ocfs2_lock_res *lockres);
370 static int ocfs2_inode_lock_update(struct inode *inode,
371 struct buffer_head **bh);
372 static void ocfs2_drop_osb_locks(struct ocfs2_super *osb);
373 static inline int ocfs2_highest_compat_lock_level(int level);
374 static unsigned int ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
376 static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
377 struct ocfs2_lock_res *lockres,
380 unsigned int generation);
381 static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
382 struct ocfs2_lock_res *lockres);
383 static int ocfs2_cancel_convert(struct ocfs2_super *osb,
384 struct ocfs2_lock_res *lockres);
387 static void ocfs2_build_lock_name(enum ocfs2_lock_type type,
394 BUG_ON(type >= OCFS2_NUM_LOCK_TYPES);
396 len = snprintf(name, OCFS2_LOCK_ID_MAX_LEN, "%c%s%016llx%08x",
397 ocfs2_lock_type_char(type), OCFS2_LOCK_ID_PAD,
398 (long long)blkno, generation);
400 BUG_ON(len != (OCFS2_LOCK_ID_MAX_LEN - 1));
402 mlog(0, "built lock resource with name: %s\n", name);
405 static DEFINE_SPINLOCK(ocfs2_dlm_tracking_lock);
407 static void ocfs2_add_lockres_tracking(struct ocfs2_lock_res *res,
408 struct ocfs2_dlm_debug *dlm_debug)
410 mlog(0, "Add tracking for lockres %s\n", res->l_name);
412 spin_lock(&ocfs2_dlm_tracking_lock);
413 list_add(&res->l_debug_list, &dlm_debug->d_lockres_tracking);
414 spin_unlock(&ocfs2_dlm_tracking_lock);
417 static void ocfs2_remove_lockres_tracking(struct ocfs2_lock_res *res)
419 spin_lock(&ocfs2_dlm_tracking_lock);
420 if (!list_empty(&res->l_debug_list))
421 list_del_init(&res->l_debug_list);
422 spin_unlock(&ocfs2_dlm_tracking_lock);
425 #ifdef CONFIG_OCFS2_FS_STATS
426 static void ocfs2_init_lock_stats(struct ocfs2_lock_res *res)
428 res->l_lock_refresh = 0;
429 res->l_lock_wait = 0;
430 memset(&res->l_lock_prmode, 0, sizeof(struct ocfs2_lock_stats));
431 memset(&res->l_lock_exmode, 0, sizeof(struct ocfs2_lock_stats));
434 static void ocfs2_update_lock_stats(struct ocfs2_lock_res *res, int level,
435 struct ocfs2_mask_waiter *mw, int ret)
439 struct ocfs2_lock_stats *stats;
441 if (level == LKM_PRMODE)
442 stats = &res->l_lock_prmode;
443 else if (level == LKM_EXMODE)
444 stats = &res->l_lock_exmode;
448 kt = ktime_sub(ktime_get(), mw->mw_lock_start);
449 usec = ktime_to_us(kt);
452 stats->ls_total += ktime_to_ns(kt);
454 if (unlikely(stats->ls_gets == 0)) {
456 stats->ls_total = ktime_to_ns(kt);
459 if (stats->ls_max < usec)
460 stats->ls_max = usec;
465 stats->ls_last = ktime_to_us(ktime_get_real());
468 static inline void ocfs2_track_lock_refresh(struct ocfs2_lock_res *lockres)
470 lockres->l_lock_refresh++;
473 static inline void ocfs2_track_lock_wait(struct ocfs2_lock_res *lockres)
475 struct ocfs2_mask_waiter *mw;
477 if (list_empty(&lockres->l_mask_waiters)) {
478 lockres->l_lock_wait = 0;
482 mw = list_first_entry(&lockres->l_mask_waiters,
483 struct ocfs2_mask_waiter, mw_item);
484 lockres->l_lock_wait =
485 ktime_to_us(ktime_mono_to_real(mw->mw_lock_start));
488 static inline void ocfs2_init_start_time(struct ocfs2_mask_waiter *mw)
490 mw->mw_lock_start = ktime_get();
493 static inline void ocfs2_init_lock_stats(struct ocfs2_lock_res *res)
496 static inline void ocfs2_update_lock_stats(struct ocfs2_lock_res *res,
497 int level, struct ocfs2_mask_waiter *mw, int ret)
500 static inline void ocfs2_track_lock_refresh(struct ocfs2_lock_res *lockres)
503 static inline void ocfs2_track_lock_wait(struct ocfs2_lock_res *lockres)
506 static inline void ocfs2_init_start_time(struct ocfs2_mask_waiter *mw)
511 static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
512 struct ocfs2_lock_res *res,
513 enum ocfs2_lock_type type,
514 struct ocfs2_lock_res_ops *ops,
521 res->l_level = DLM_LOCK_IV;
522 res->l_requested = DLM_LOCK_IV;
523 res->l_blocking = DLM_LOCK_IV;
524 res->l_action = OCFS2_AST_INVALID;
525 res->l_unlock_action = OCFS2_UNLOCK_INVALID;
527 res->l_flags = OCFS2_LOCK_INITIALIZED;
529 ocfs2_add_lockres_tracking(res, osb->osb_dlm_debug);
531 ocfs2_init_lock_stats(res);
532 #ifdef CONFIG_DEBUG_LOCK_ALLOC
533 if (type != OCFS2_LOCK_TYPE_OPEN)
534 lockdep_init_map(&res->l_lockdep_map, ocfs2_lock_type_strings[type],
535 &lockdep_keys[type], 0);
537 res->l_lockdep_map.key = NULL;
541 void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res)
543 /* This also clears out the lock status block */
544 memset(res, 0, sizeof(struct ocfs2_lock_res));
545 spin_lock_init(&res->l_lock);
546 init_waitqueue_head(&res->l_event);
547 INIT_LIST_HEAD(&res->l_blocked_list);
548 INIT_LIST_HEAD(&res->l_mask_waiters);
549 INIT_LIST_HEAD(&res->l_holders);
552 void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
553 enum ocfs2_lock_type type,
554 unsigned int generation,
557 struct ocfs2_lock_res_ops *ops;
560 case OCFS2_LOCK_TYPE_RW:
561 ops = &ocfs2_inode_rw_lops;
563 case OCFS2_LOCK_TYPE_META:
564 ops = &ocfs2_inode_inode_lops;
566 case OCFS2_LOCK_TYPE_OPEN:
567 ops = &ocfs2_inode_open_lops;
570 mlog_bug_on_msg(1, "type: %d\n", type);
571 ops = NULL; /* thanks, gcc */
575 ocfs2_build_lock_name(type, OCFS2_I(inode)->ip_blkno,
576 generation, res->l_name);
577 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), res, type, ops, inode);
580 static struct ocfs2_super *ocfs2_get_inode_osb(struct ocfs2_lock_res *lockres)
582 struct inode *inode = ocfs2_lock_res_inode(lockres);
584 return OCFS2_SB(inode->i_sb);
587 static struct ocfs2_super *ocfs2_get_qinfo_osb(struct ocfs2_lock_res *lockres)
589 struct ocfs2_mem_dqinfo *info = lockres->l_priv;
591 return OCFS2_SB(info->dqi_gi.dqi_sb);
594 static struct ocfs2_super *ocfs2_get_file_osb(struct ocfs2_lock_res *lockres)
596 struct ocfs2_file_private *fp = lockres->l_priv;
598 return OCFS2_SB(fp->fp_file->f_mapping->host->i_sb);
601 static __u64 ocfs2_get_dentry_lock_ino(struct ocfs2_lock_res *lockres)
603 __be64 inode_blkno_be;
605 memcpy(&inode_blkno_be, &lockres->l_name[OCFS2_DENTRY_LOCK_INO_START],
608 return be64_to_cpu(inode_blkno_be);
611 static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres)
613 struct ocfs2_dentry_lock *dl = lockres->l_priv;
615 return OCFS2_SB(dl->dl_inode->i_sb);
618 void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
619 u64 parent, struct inode *inode)
622 u64 inode_blkno = OCFS2_I(inode)->ip_blkno;
623 __be64 inode_blkno_be = cpu_to_be64(inode_blkno);
624 struct ocfs2_lock_res *lockres = &dl->dl_lockres;
626 ocfs2_lock_res_init_once(lockres);
629 * Unfortunately, the standard lock naming scheme won't work
630 * here because we have two 16 byte values to use. Instead,
631 * we'll stuff the inode number as a binary value. We still
632 * want error prints to show something without garbling the
633 * display, so drop a null byte in there before the inode
634 * number. A future version of OCFS2 will likely use all
635 * binary lock names. The stringified names have been a
636 * tremendous aid in debugging, but now that the debugfs
637 * interface exists, we can mangle things there if need be.
639 * NOTE: We also drop the standard "pad" value (the total lock
640 * name size stays the same though - the last part is all
641 * zeros due to the memset in ocfs2_lock_res_init_once()
643 len = snprintf(lockres->l_name, OCFS2_DENTRY_LOCK_INO_START,
645 ocfs2_lock_type_char(OCFS2_LOCK_TYPE_DENTRY),
648 BUG_ON(len != (OCFS2_DENTRY_LOCK_INO_START - 1));
650 memcpy(&lockres->l_name[OCFS2_DENTRY_LOCK_INO_START], &inode_blkno_be,
653 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
654 OCFS2_LOCK_TYPE_DENTRY, &ocfs2_dentry_lops,
658 static void ocfs2_super_lock_res_init(struct ocfs2_lock_res *res,
659 struct ocfs2_super *osb)
661 /* Superblock lockres doesn't come from a slab so we call init
662 * once on it manually. */
663 ocfs2_lock_res_init_once(res);
664 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_SUPER, OCFS2_SUPER_BLOCK_BLKNO,
666 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_SUPER,
667 &ocfs2_super_lops, osb);
670 static void ocfs2_rename_lock_res_init(struct ocfs2_lock_res *res,
671 struct ocfs2_super *osb)
673 /* Rename lockres doesn't come from a slab so we call init
674 * once on it manually. */
675 ocfs2_lock_res_init_once(res);
676 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_RENAME, 0, 0, res->l_name);
677 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_RENAME,
678 &ocfs2_rename_lops, osb);
681 static void ocfs2_nfs_sync_lock_res_init(struct ocfs2_lock_res *res,
682 struct ocfs2_super *osb)
684 /* nfs_sync lockres doesn't come from a slab so we call init
685 * once on it manually. */
686 ocfs2_lock_res_init_once(res);
687 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_NFS_SYNC, 0, 0, res->l_name);
688 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_NFS_SYNC,
689 &ocfs2_nfs_sync_lops, osb);
692 void ocfs2_trim_fs_lock_res_init(struct ocfs2_super *osb)
694 struct ocfs2_lock_res *lockres = &osb->osb_trim_fs_lockres;
696 /* Only one trimfs thread are allowed to work at the same time. */
697 mutex_lock(&osb->obs_trim_fs_mutex);
699 ocfs2_lock_res_init_once(lockres);
700 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_TRIM_FS, 0, 0, lockres->l_name);
701 ocfs2_lock_res_init_common(osb, lockres, OCFS2_LOCK_TYPE_TRIM_FS,
702 &ocfs2_trim_fs_lops, osb);
705 void ocfs2_trim_fs_lock_res_uninit(struct ocfs2_super *osb)
707 struct ocfs2_lock_res *lockres = &osb->osb_trim_fs_lockres;
709 ocfs2_simple_drop_lockres(osb, lockres);
710 ocfs2_lock_res_free(lockres);
712 mutex_unlock(&osb->obs_trim_fs_mutex);
715 static void ocfs2_orphan_scan_lock_res_init(struct ocfs2_lock_res *res,
716 struct ocfs2_super *osb)
718 ocfs2_lock_res_init_once(res);
719 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_ORPHAN_SCAN, 0, 0, res->l_name);
720 ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_ORPHAN_SCAN,
721 &ocfs2_orphan_scan_lops, osb);
724 void ocfs2_file_lock_res_init(struct ocfs2_lock_res *lockres,
725 struct ocfs2_file_private *fp)
727 struct inode *inode = fp->fp_file->f_mapping->host;
728 struct ocfs2_inode_info *oi = OCFS2_I(inode);
730 ocfs2_lock_res_init_once(lockres);
731 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_FLOCK, oi->ip_blkno,
732 inode->i_generation, lockres->l_name);
733 ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
734 OCFS2_LOCK_TYPE_FLOCK, &ocfs2_flock_lops,
736 lockres->l_flags |= OCFS2_LOCK_NOCACHE;
739 void ocfs2_qinfo_lock_res_init(struct ocfs2_lock_res *lockres,
740 struct ocfs2_mem_dqinfo *info)
742 ocfs2_lock_res_init_once(lockres);
743 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_QINFO, info->dqi_gi.dqi_type,
745 ocfs2_lock_res_init_common(OCFS2_SB(info->dqi_gi.dqi_sb), lockres,
746 OCFS2_LOCK_TYPE_QINFO, &ocfs2_qinfo_lops,
750 void ocfs2_refcount_lock_res_init(struct ocfs2_lock_res *lockres,
751 struct ocfs2_super *osb, u64 ref_blkno,
752 unsigned int generation)
754 ocfs2_lock_res_init_once(lockres);
755 ocfs2_build_lock_name(OCFS2_LOCK_TYPE_REFCOUNT, ref_blkno,
756 generation, lockres->l_name);
757 ocfs2_lock_res_init_common(osb, lockres, OCFS2_LOCK_TYPE_REFCOUNT,
758 &ocfs2_refcount_block_lops, osb);
761 void ocfs2_lock_res_free(struct ocfs2_lock_res *res)
763 if (!(res->l_flags & OCFS2_LOCK_INITIALIZED))
766 ocfs2_remove_lockres_tracking(res);
768 mlog_bug_on_msg(!list_empty(&res->l_blocked_list),
769 "Lockres %s is on the blocked list\n",
771 mlog_bug_on_msg(!list_empty(&res->l_mask_waiters),
772 "Lockres %s has mask waiters pending\n",
774 mlog_bug_on_msg(spin_is_locked(&res->l_lock),
775 "Lockres %s is locked\n",
777 mlog_bug_on_msg(res->l_ro_holders,
778 "Lockres %s has %u ro holders\n",
779 res->l_name, res->l_ro_holders);
780 mlog_bug_on_msg(res->l_ex_holders,
781 "Lockres %s has %u ex holders\n",
782 res->l_name, res->l_ex_holders);
784 /* Need to clear out the lock status block for the dlm */
785 memset(&res->l_lksb, 0, sizeof(res->l_lksb));
791 * Keep a list of processes who have interest in a lockres.
792 * Note: this is now only uesed for check recursive cluster locking.
794 static inline void ocfs2_add_holder(struct ocfs2_lock_res *lockres,
795 struct ocfs2_lock_holder *oh)
797 INIT_LIST_HEAD(&oh->oh_list);
798 oh->oh_owner_pid = get_pid(task_pid(current));
800 spin_lock(&lockres->l_lock);
801 list_add_tail(&oh->oh_list, &lockres->l_holders);
802 spin_unlock(&lockres->l_lock);
805 static struct ocfs2_lock_holder *
806 ocfs2_pid_holder(struct ocfs2_lock_res *lockres,
809 struct ocfs2_lock_holder *oh;
811 spin_lock(&lockres->l_lock);
812 list_for_each_entry(oh, &lockres->l_holders, oh_list) {
813 if (oh->oh_owner_pid == pid) {
814 spin_unlock(&lockres->l_lock);
818 spin_unlock(&lockres->l_lock);
822 static inline void ocfs2_remove_holder(struct ocfs2_lock_res *lockres,
823 struct ocfs2_lock_holder *oh)
825 spin_lock(&lockres->l_lock);
826 list_del(&oh->oh_list);
827 spin_unlock(&lockres->l_lock);
829 put_pid(oh->oh_owner_pid);
833 static inline void ocfs2_inc_holders(struct ocfs2_lock_res *lockres,
840 lockres->l_ex_holders++;
843 lockres->l_ro_holders++;
850 static inline void ocfs2_dec_holders(struct ocfs2_lock_res *lockres,
857 BUG_ON(!lockres->l_ex_holders);
858 lockres->l_ex_holders--;
861 BUG_ON(!lockres->l_ro_holders);
862 lockres->l_ro_holders--;
869 /* WARNING: This function lives in a world where the only three lock
870 * levels are EX, PR, and NL. It *will* have to be adjusted when more
871 * lock types are added. */
872 static inline int ocfs2_highest_compat_lock_level(int level)
874 int new_level = DLM_LOCK_EX;
876 if (level == DLM_LOCK_EX)
877 new_level = DLM_LOCK_NL;
878 else if (level == DLM_LOCK_PR)
879 new_level = DLM_LOCK_PR;
883 static void lockres_set_flags(struct ocfs2_lock_res *lockres,
884 unsigned long newflags)
886 struct ocfs2_mask_waiter *mw, *tmp;
888 assert_spin_locked(&lockres->l_lock);
890 lockres->l_flags = newflags;
892 list_for_each_entry_safe(mw, tmp, &lockres->l_mask_waiters, mw_item) {
893 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
896 list_del_init(&mw->mw_item);
898 complete(&mw->mw_complete);
899 ocfs2_track_lock_wait(lockres);
902 static void lockres_or_flags(struct ocfs2_lock_res *lockres, unsigned long or)
904 lockres_set_flags(lockres, lockres->l_flags | or);
906 static void lockres_clear_flags(struct ocfs2_lock_res *lockres,
909 lockres_set_flags(lockres, lockres->l_flags & ~clear);
912 static inline void ocfs2_generic_handle_downconvert_action(struct ocfs2_lock_res *lockres)
914 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
915 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
916 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
917 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
919 lockres->l_level = lockres->l_requested;
920 if (lockres->l_level <=
921 ocfs2_highest_compat_lock_level(lockres->l_blocking)) {
922 lockres->l_blocking = DLM_LOCK_NL;
923 lockres_clear_flags(lockres, OCFS2_LOCK_BLOCKED);
925 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
928 static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lockres)
930 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
931 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_ATTACHED));
933 /* Convert from RO to EX doesn't really need anything as our
934 * information is already up to data. Convert from NL to
935 * *anything* however should mark ourselves as needing an
937 if (lockres->l_level == DLM_LOCK_NL &&
938 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
939 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
941 lockres->l_level = lockres->l_requested;
944 * We set the OCFS2_LOCK_UPCONVERT_FINISHING flag before clearing
945 * the OCFS2_LOCK_BUSY flag to prevent the dc thread from
946 * downconverting the lock before the upconvert has fully completed.
947 * Do not prevent the dc thread from downconverting if NONBLOCK lock
948 * had already returned.
950 if (!(lockres->l_flags & OCFS2_LOCK_NONBLOCK_FINISHED))
951 lockres_or_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
953 lockres_clear_flags(lockres, OCFS2_LOCK_NONBLOCK_FINISHED);
955 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
958 static inline void ocfs2_generic_handle_attach_action(struct ocfs2_lock_res *lockres)
960 BUG_ON((!(lockres->l_flags & OCFS2_LOCK_BUSY)));
961 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
963 if (lockres->l_requested > DLM_LOCK_NL &&
964 !(lockres->l_flags & OCFS2_LOCK_LOCAL) &&
965 lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
966 lockres_or_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
968 lockres->l_level = lockres->l_requested;
969 lockres_or_flags(lockres, OCFS2_LOCK_ATTACHED);
970 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
973 static int ocfs2_generic_handle_bast(struct ocfs2_lock_res *lockres,
976 int needs_downconvert = 0;
978 assert_spin_locked(&lockres->l_lock);
980 if (level > lockres->l_blocking) {
981 /* only schedule a downconvert if we haven't already scheduled
982 * one that goes low enough to satisfy the level we're
983 * blocking. this also catches the case where we get
985 if (ocfs2_highest_compat_lock_level(level) <
986 ocfs2_highest_compat_lock_level(lockres->l_blocking))
987 needs_downconvert = 1;
989 lockres->l_blocking = level;
992 mlog(ML_BASTS, "lockres %s, block %d, level %d, l_block %d, dwn %d\n",
993 lockres->l_name, level, lockres->l_level, lockres->l_blocking,
996 if (needs_downconvert)
997 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
998 mlog(0, "needs_downconvert = %d\n", needs_downconvert);
999 return needs_downconvert;
1003 * OCFS2_LOCK_PENDING and l_pending_gen.
1005 * Why does OCFS2_LOCK_PENDING exist? To close a race between setting
1006 * OCFS2_LOCK_BUSY and calling ocfs2_dlm_lock(). See ocfs2_unblock_lock()
1007 * for more details on the race.
1009 * OCFS2_LOCK_PENDING closes the race quite nicely. However, it introduces
1010 * a race on itself. In o2dlm, we can get the ast before ocfs2_dlm_lock()
1011 * returns. The ast clears OCFS2_LOCK_BUSY, and must therefore clear
1012 * OCFS2_LOCK_PENDING at the same time. When ocfs2_dlm_lock() returns,
1013 * the caller is going to try to clear PENDING again. If nothing else is
1014 * happening, __lockres_clear_pending() sees PENDING is unset and does
1017 * But what if another path (eg downconvert thread) has just started a
1018 * new locking action? The other path has re-set PENDING. Our path
1019 * cannot clear PENDING, because that will re-open the original race
1025 * ocfs2_cluster_lock()
1030 * ocfs2_locking_ast() ocfs2_downconvert_thread()
1031 * clear PENDING ocfs2_unblock_lock()
1034 * ocfs2_prepare_downconvert()
1044 * So as you can see, we now have a window where l_lock is not held,
1045 * PENDING is not set, and ocfs2_dlm_lock() has not been called.
1047 * The core problem is that ocfs2_cluster_lock() has cleared the PENDING
1048 * set by ocfs2_prepare_downconvert(). That wasn't nice.
1050 * To solve this we introduce l_pending_gen. A call to
1051 * lockres_clear_pending() will only do so when it is passed a generation
1052 * number that matches the lockres. lockres_set_pending() will return the
1053 * current generation number. When ocfs2_cluster_lock() goes to clear
1054 * PENDING, it passes the generation it got from set_pending(). In our
1055 * example above, the generation numbers will *not* match. Thus,
1056 * ocfs2_cluster_lock() will not clear the PENDING set by
1057 * ocfs2_prepare_downconvert().
1060 /* Unlocked version for ocfs2_locking_ast() */
1061 static void __lockres_clear_pending(struct ocfs2_lock_res *lockres,
1062 unsigned int generation,
1063 struct ocfs2_super *osb)
1065 assert_spin_locked(&lockres->l_lock);
1068 * The ast and locking functions can race us here. The winner
1069 * will clear pending, the loser will not.
1071 if (!(lockres->l_flags & OCFS2_LOCK_PENDING) ||
1072 (lockres->l_pending_gen != generation))
1075 lockres_clear_flags(lockres, OCFS2_LOCK_PENDING);
1076 lockres->l_pending_gen++;
1079 * The downconvert thread may have skipped us because we
1080 * were PENDING. Wake it up.
1082 if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
1083 ocfs2_wake_downconvert_thread(osb);
1086 /* Locked version for callers of ocfs2_dlm_lock() */
1087 static void lockres_clear_pending(struct ocfs2_lock_res *lockres,
1088 unsigned int generation,
1089 struct ocfs2_super *osb)
1091 unsigned long flags;
1093 spin_lock_irqsave(&lockres->l_lock, flags);
1094 __lockres_clear_pending(lockres, generation, osb);
1095 spin_unlock_irqrestore(&lockres->l_lock, flags);
1098 static unsigned int lockres_set_pending(struct ocfs2_lock_res *lockres)
1100 assert_spin_locked(&lockres->l_lock);
1101 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BUSY));
1103 lockres_or_flags(lockres, OCFS2_LOCK_PENDING);
1105 return lockres->l_pending_gen;
1108 static void ocfs2_blocking_ast(struct ocfs2_dlm_lksb *lksb, int level)
1110 struct ocfs2_lock_res *lockres = ocfs2_lksb_to_lock_res(lksb);
1111 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
1112 int needs_downconvert;
1113 unsigned long flags;
1115 BUG_ON(level <= DLM_LOCK_NL);
1117 mlog(ML_BASTS, "BAST fired for lockres %s, blocking %d, level %d, "
1118 "type %s\n", lockres->l_name, level, lockres->l_level,
1119 ocfs2_lock_type_string(lockres->l_type));
1122 * We can skip the bast for locks which don't enable caching -
1123 * they'll be dropped at the earliest possible time anyway.
1125 if (lockres->l_flags & OCFS2_LOCK_NOCACHE)
1128 spin_lock_irqsave(&lockres->l_lock, flags);
1129 needs_downconvert = ocfs2_generic_handle_bast(lockres, level);
1130 if (needs_downconvert)
1131 ocfs2_schedule_blocked_lock(osb, lockres);
1132 spin_unlock_irqrestore(&lockres->l_lock, flags);
1134 wake_up(&lockres->l_event);
1136 ocfs2_wake_downconvert_thread(osb);
1139 static void ocfs2_locking_ast(struct ocfs2_dlm_lksb *lksb)
1141 struct ocfs2_lock_res *lockres = ocfs2_lksb_to_lock_res(lksb);
1142 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
1143 unsigned long flags;
1146 spin_lock_irqsave(&lockres->l_lock, flags);
1148 status = ocfs2_dlm_lock_status(&lockres->l_lksb);
1150 if (status == -EAGAIN) {
1151 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
1156 mlog(ML_ERROR, "lockres %s: lksb status value of %d!\n",
1157 lockres->l_name, status);
1158 spin_unlock_irqrestore(&lockres->l_lock, flags);
1162 mlog(ML_BASTS, "AST fired for lockres %s, action %d, unlock %d, "
1163 "level %d => %d\n", lockres->l_name, lockres->l_action,
1164 lockres->l_unlock_action, lockres->l_level, lockres->l_requested);
1166 switch(lockres->l_action) {
1167 case OCFS2_AST_ATTACH:
1168 ocfs2_generic_handle_attach_action(lockres);
1169 lockres_clear_flags(lockres, OCFS2_LOCK_LOCAL);
1171 case OCFS2_AST_CONVERT:
1172 ocfs2_generic_handle_convert_action(lockres);
1174 case OCFS2_AST_DOWNCONVERT:
1175 ocfs2_generic_handle_downconvert_action(lockres);
1178 mlog(ML_ERROR, "lockres %s: AST fired with invalid action: %u, "
1179 "flags 0x%lx, unlock: %u\n",
1180 lockres->l_name, lockres->l_action, lockres->l_flags,
1181 lockres->l_unlock_action);
1185 /* set it to something invalid so if we get called again we
1187 lockres->l_action = OCFS2_AST_INVALID;
1189 /* Did we try to cancel this lock? Clear that state */
1190 if (lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT)
1191 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
1194 * We may have beaten the locking functions here. We certainly
1195 * know that dlm_lock() has been called :-)
1196 * Because we can't have two lock calls in flight at once, we
1197 * can use lockres->l_pending_gen.
1199 __lockres_clear_pending(lockres, lockres->l_pending_gen, osb);
1201 wake_up(&lockres->l_event);
1202 spin_unlock_irqrestore(&lockres->l_lock, flags);
1205 static void ocfs2_unlock_ast(struct ocfs2_dlm_lksb *lksb, int error)
1207 struct ocfs2_lock_res *lockres = ocfs2_lksb_to_lock_res(lksb);
1208 unsigned long flags;
1210 mlog(ML_BASTS, "UNLOCK AST fired for lockres %s, action = %d\n",
1211 lockres->l_name, lockres->l_unlock_action);
1213 spin_lock_irqsave(&lockres->l_lock, flags);
1215 mlog(ML_ERROR, "Dlm passes error %d for lock %s, "
1216 "unlock_action %d\n", error, lockres->l_name,
1217 lockres->l_unlock_action);
1218 spin_unlock_irqrestore(&lockres->l_lock, flags);
1222 switch(lockres->l_unlock_action) {
1223 case OCFS2_UNLOCK_CANCEL_CONVERT:
1224 mlog(0, "Cancel convert success for %s\n", lockres->l_name);
1225 lockres->l_action = OCFS2_AST_INVALID;
1226 /* Downconvert thread may have requeued this lock, we
1227 * need to wake it. */
1228 if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
1229 ocfs2_wake_downconvert_thread(ocfs2_get_lockres_osb(lockres));
1231 case OCFS2_UNLOCK_DROP_LOCK:
1232 lockres->l_level = DLM_LOCK_IV;
1238 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
1239 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
1240 wake_up(&lockres->l_event);
1241 spin_unlock_irqrestore(&lockres->l_lock, flags);
1245 * This is the filesystem locking protocol. It provides the lock handling
1246 * hooks for the underlying DLM. It has a maximum version number.
1247 * The version number allows interoperability with systems running at
1248 * the same major number and an equal or smaller minor number.
1250 * Whenever the filesystem does new things with locks (adds or removes a
1251 * lock, orders them differently, does different things underneath a lock),
1252 * the version must be changed. The protocol is negotiated when joining
1253 * the dlm domain. A node may join the domain if its major version is
1254 * identical to all other nodes and its minor version is greater than
1255 * or equal to all other nodes. When its minor version is greater than
1256 * the other nodes, it will run at the minor version specified by the
1259 * If a locking change is made that will not be compatible with older
1260 * versions, the major number must be increased and the minor version set
1261 * to zero. If a change merely adds a behavior that can be disabled when
1262 * speaking to older versions, the minor version must be increased. If a
1263 * change adds a fully backwards compatible change (eg, LVB changes that
1264 * are just ignored by older versions), the version does not need to be
1267 static struct ocfs2_locking_protocol lproto = {
1269 .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
1270 .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
1272 .lp_lock_ast = ocfs2_locking_ast,
1273 .lp_blocking_ast = ocfs2_blocking_ast,
1274 .lp_unlock_ast = ocfs2_unlock_ast,
1277 void ocfs2_set_locking_protocol(void)
1279 ocfs2_stack_glue_set_max_proto_version(&lproto.lp_max_version);
1282 static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
1285 unsigned long flags;
1287 spin_lock_irqsave(&lockres->l_lock, flags);
1288 lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
1289 lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
1291 lockres->l_action = OCFS2_AST_INVALID;
1293 lockres->l_unlock_action = OCFS2_UNLOCK_INVALID;
1294 spin_unlock_irqrestore(&lockres->l_lock, flags);
1296 wake_up(&lockres->l_event);
1299 /* Note: If we detect another process working on the lock (i.e.,
1300 * OCFS2_LOCK_BUSY), we'll bail out returning 0. It's up to the caller
1301 * to do the right thing in that case.
1303 static int ocfs2_lock_create(struct ocfs2_super *osb,
1304 struct ocfs2_lock_res *lockres,
1309 unsigned long flags;
1312 mlog(0, "lock %s, level = %d, flags = %u\n", lockres->l_name, level,
1315 spin_lock_irqsave(&lockres->l_lock, flags);
1316 if ((lockres->l_flags & OCFS2_LOCK_ATTACHED) ||
1317 (lockres->l_flags & OCFS2_LOCK_BUSY)) {
1318 spin_unlock_irqrestore(&lockres->l_lock, flags);
1322 lockres->l_action = OCFS2_AST_ATTACH;
1323 lockres->l_requested = level;
1324 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1325 gen = lockres_set_pending(lockres);
1326 spin_unlock_irqrestore(&lockres->l_lock, flags);
1328 ret = ocfs2_dlm_lock(osb->cconn,
1333 OCFS2_LOCK_ID_MAX_LEN - 1);
1334 lockres_clear_pending(lockres, gen, osb);
1336 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
1337 ocfs2_recover_from_dlm_error(lockres, 1);
1340 mlog(0, "lock %s, return from ocfs2_dlm_lock\n", lockres->l_name);
1346 static inline int ocfs2_check_wait_flag(struct ocfs2_lock_res *lockres,
1349 unsigned long flags;
1352 spin_lock_irqsave(&lockres->l_lock, flags);
1353 ret = lockres->l_flags & flag;
1354 spin_unlock_irqrestore(&lockres->l_lock, flags);
1359 static inline void ocfs2_wait_on_busy_lock(struct ocfs2_lock_res *lockres)
1362 wait_event(lockres->l_event,
1363 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_BUSY));
1366 static inline void ocfs2_wait_on_refreshing_lock(struct ocfs2_lock_res *lockres)
1369 wait_event(lockres->l_event,
1370 !ocfs2_check_wait_flag(lockres, OCFS2_LOCK_REFRESHING));
1373 /* predict what lock level we'll be dropping down to on behalf
1374 * of another node, and return true if the currently wanted
1375 * level will be compatible with it. */
1376 static inline int ocfs2_may_continue_on_blocked_lock(struct ocfs2_lock_res *lockres,
1379 BUG_ON(!(lockres->l_flags & OCFS2_LOCK_BLOCKED));
1381 return wanted <= ocfs2_highest_compat_lock_level(lockres->l_blocking);
1384 static void ocfs2_init_mask_waiter(struct ocfs2_mask_waiter *mw)
1386 INIT_LIST_HEAD(&mw->mw_item);
1387 init_completion(&mw->mw_complete);
1388 ocfs2_init_start_time(mw);
1391 static int ocfs2_wait_for_mask(struct ocfs2_mask_waiter *mw)
1393 wait_for_completion(&mw->mw_complete);
1394 /* Re-arm the completion in case we want to wait on it again */
1395 reinit_completion(&mw->mw_complete);
1396 return mw->mw_status;
1399 static void lockres_add_mask_waiter(struct ocfs2_lock_res *lockres,
1400 struct ocfs2_mask_waiter *mw,
1404 BUG_ON(!list_empty(&mw->mw_item));
1406 assert_spin_locked(&lockres->l_lock);
1408 list_add_tail(&mw->mw_item, &lockres->l_mask_waiters);
1411 ocfs2_track_lock_wait(lockres);
1414 /* returns 0 if the mw that was removed was already satisfied, -EBUSY
1415 * if the mask still hadn't reached its goal */
1416 static int __lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
1417 struct ocfs2_mask_waiter *mw)
1421 assert_spin_locked(&lockres->l_lock);
1422 if (!list_empty(&mw->mw_item)) {
1423 if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
1426 list_del_init(&mw->mw_item);
1427 init_completion(&mw->mw_complete);
1428 ocfs2_track_lock_wait(lockres);
1434 static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
1435 struct ocfs2_mask_waiter *mw)
1437 unsigned long flags;
1440 spin_lock_irqsave(&lockres->l_lock, flags);
1441 ret = __lockres_remove_mask_waiter(lockres, mw);
1442 spin_unlock_irqrestore(&lockres->l_lock, flags);
1448 static int ocfs2_wait_for_mask_interruptible(struct ocfs2_mask_waiter *mw,
1449 struct ocfs2_lock_res *lockres)
1453 ret = wait_for_completion_interruptible(&mw->mw_complete);
1455 lockres_remove_mask_waiter(lockres, mw);
1457 ret = mw->mw_status;
1458 /* Re-arm the completion in case we want to wait on it again */
1459 reinit_completion(&mw->mw_complete);
1463 static int __ocfs2_cluster_lock(struct ocfs2_super *osb,
1464 struct ocfs2_lock_res *lockres,
1469 unsigned long caller_ip)
1471 struct ocfs2_mask_waiter mw;
1472 int wait, catch_signals = !(osb->s_mount_opt & OCFS2_MOUNT_NOINTR);
1473 int ret = 0; /* gcc doesn't realize wait = 1 guarantees ret is set */
1474 unsigned long flags;
1476 int noqueue_attempted = 0;
1480 if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) {
1481 mlog_errno(-EINVAL);
1485 ocfs2_init_mask_waiter(&mw);
1487 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
1488 lkm_flags |= DLM_LKF_VALBLK;
1493 spin_lock_irqsave(&lockres->l_lock, flags);
1495 if (catch_signals && signal_pending(current)) {
1500 mlog_bug_on_msg(lockres->l_flags & OCFS2_LOCK_FREEING,
1501 "Cluster lock called on freeing lockres %s! flags "
1502 "0x%lx\n", lockres->l_name, lockres->l_flags);
1504 /* We only compare against the currently granted level
1505 * here. If the lock is blocked waiting on a downconvert,
1506 * we'll get caught below. */
1507 if (lockres->l_flags & OCFS2_LOCK_BUSY &&
1508 level > lockres->l_level) {
1509 /* is someone sitting in dlm_lock? If so, wait on
1511 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1516 if (lockres->l_flags & OCFS2_LOCK_UPCONVERT_FINISHING) {
1518 * We've upconverted. If the lock now has a level we can
1519 * work with, we take it. If, however, the lock is not at the
1520 * required level, we go thru the full cycle. One way this could
1521 * happen is if a process requesting an upconvert to PR is
1522 * closely followed by another requesting upconvert to an EX.
1523 * If the process requesting EX lands here, we want it to
1524 * continue attempting to upconvert and let the process
1525 * requesting PR take the lock.
1526 * If multiple processes request upconvert to PR, the first one
1527 * here will take the lock. The others will have to go thru the
1528 * OCFS2_LOCK_BLOCKED check to ensure that there is no pending
1529 * downconvert request.
1531 if (level <= lockres->l_level)
1532 goto update_holders;
1535 if (lockres->l_flags & OCFS2_LOCK_BLOCKED &&
1536 !ocfs2_may_continue_on_blocked_lock(lockres, level)) {
1537 /* is the lock is currently blocked on behalf of
1539 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BLOCKED, 0);
1544 if (level > lockres->l_level) {
1545 if (noqueue_attempted > 0) {
1549 if (lkm_flags & DLM_LKF_NOQUEUE)
1550 noqueue_attempted = 1;
1552 if (lockres->l_action != OCFS2_AST_INVALID)
1553 mlog(ML_ERROR, "lockres %s has action %u pending\n",
1554 lockres->l_name, lockres->l_action);
1556 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1557 lockres->l_action = OCFS2_AST_ATTACH;
1558 lkm_flags &= ~DLM_LKF_CONVERT;
1560 lockres->l_action = OCFS2_AST_CONVERT;
1561 lkm_flags |= DLM_LKF_CONVERT;
1564 lockres->l_requested = level;
1565 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
1566 gen = lockres_set_pending(lockres);
1567 spin_unlock_irqrestore(&lockres->l_lock, flags);
1569 BUG_ON(level == DLM_LOCK_IV);
1570 BUG_ON(level == DLM_LOCK_NL);
1572 mlog(ML_BASTS, "lockres %s, convert from %d to %d\n",
1573 lockres->l_name, lockres->l_level, level);
1575 /* call dlm_lock to upgrade lock now */
1576 ret = ocfs2_dlm_lock(osb->cconn,
1581 OCFS2_LOCK_ID_MAX_LEN - 1);
1582 lockres_clear_pending(lockres, gen, osb);
1584 if (!(lkm_flags & DLM_LKF_NOQUEUE) ||
1586 ocfs2_log_dlm_error("ocfs2_dlm_lock",
1589 ocfs2_recover_from_dlm_error(lockres, 1);
1594 mlog(0, "lock %s, successful return from ocfs2_dlm_lock\n",
1597 /* At this point we've gone inside the dlm and need to
1598 * complete our work regardless. */
1601 /* wait for busy to clear and carry on */
1606 /* Ok, if we get here then we're good to go. */
1607 ocfs2_inc_holders(lockres, level);
1611 lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
1613 /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */
1614 kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED);
1616 spin_unlock_irqrestore(&lockres->l_lock, flags);
1618 ocfs2_wake_downconvert_thread(osb);
1621 * This is helping work around a lock inversion between the page lock
1622 * and dlm locks. One path holds the page lock while calling aops
1623 * which block acquiring dlm locks. The voting thread holds dlm
1624 * locks while acquiring page locks while down converting data locks.
1625 * This block is helping an aop path notice the inversion and back
1626 * off to unlock its page lock before trying the dlm lock again.
1628 if (wait && arg_flags & OCFS2_LOCK_NONBLOCK &&
1629 mw.mw_mask & (OCFS2_LOCK_BUSY|OCFS2_LOCK_BLOCKED)) {
1631 spin_lock_irqsave(&lockres->l_lock, flags);
1632 if (__lockres_remove_mask_waiter(lockres, &mw)) {
1634 lockres_or_flags(lockres,
1635 OCFS2_LOCK_NONBLOCK_FINISHED);
1636 spin_unlock_irqrestore(&lockres->l_lock, flags);
1639 spin_unlock_irqrestore(&lockres->l_lock, flags);
1644 ret = ocfs2_wait_for_mask(&mw);
1649 ocfs2_update_lock_stats(lockres, level, &mw, ret);
1651 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1652 if (!ret && lockres->l_lockdep_map.key != NULL) {
1653 if (level == DLM_LOCK_PR)
1654 rwsem_acquire_read(&lockres->l_lockdep_map, l_subclass,
1655 !!(arg_flags & OCFS2_META_LOCK_NOQUEUE),
1658 rwsem_acquire(&lockres->l_lockdep_map, l_subclass,
1659 !!(arg_flags & OCFS2_META_LOCK_NOQUEUE),
1666 static inline int ocfs2_cluster_lock(struct ocfs2_super *osb,
1667 struct ocfs2_lock_res *lockres,
1672 return __ocfs2_cluster_lock(osb, lockres, level, lkm_flags, arg_flags,
1677 static void __ocfs2_cluster_unlock(struct ocfs2_super *osb,
1678 struct ocfs2_lock_res *lockres,
1680 unsigned long caller_ip)
1682 unsigned long flags;
1684 spin_lock_irqsave(&lockres->l_lock, flags);
1685 ocfs2_dec_holders(lockres, level);
1686 ocfs2_downconvert_on_unlock(osb, lockres);
1687 spin_unlock_irqrestore(&lockres->l_lock, flags);
1688 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1689 if (lockres->l_lockdep_map.key != NULL)
1690 rwsem_release(&lockres->l_lockdep_map, 1, caller_ip);
1694 static int ocfs2_create_new_lock(struct ocfs2_super *osb,
1695 struct ocfs2_lock_res *lockres,
1699 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
1700 unsigned long flags;
1701 u32 lkm_flags = local ? DLM_LKF_LOCAL : 0;
1703 spin_lock_irqsave(&lockres->l_lock, flags);
1704 BUG_ON(lockres->l_flags & OCFS2_LOCK_ATTACHED);
1705 lockres_or_flags(lockres, OCFS2_LOCK_LOCAL);
1706 spin_unlock_irqrestore(&lockres->l_lock, flags);
1708 return ocfs2_lock_create(osb, lockres, level, lkm_flags);
1711 /* Grants us an EX lock on the data and metadata resources, skipping
1712 * the normal cluster directory lookup. Use this ONLY on newly created
1713 * inodes which other nodes can't possibly see, and which haven't been
1714 * hashed in the inode hash yet. This can give us a good performance
1715 * increase as it'll skip the network broadcast normally associated
1716 * with creating a new lock resource. */
1717 int ocfs2_create_new_inode_locks(struct inode *inode)
1720 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1722 BUG_ON(!ocfs2_inode_is_new(inode));
1724 mlog(0, "Inode %llu\n", (unsigned long long)OCFS2_I(inode)->ip_blkno);
1726 /* NOTE: That we don't increment any of the holder counts, nor
1727 * do we add anything to a journal handle. Since this is
1728 * supposed to be a new inode which the cluster doesn't know
1729 * about yet, there is no need to. As far as the LVB handling
1730 * is concerned, this is basically like acquiring an EX lock
1731 * on a resource which has an invalid one -- we'll set it
1732 * valid when we release the EX. */
1734 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_rw_lockres, 1, 1);
1741 * We don't want to use DLM_LKF_LOCAL on a meta data lock as they
1742 * don't use a generation in their lock names.
1744 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_inode_lockres, 1, 0);
1750 ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_open_lockres, 0, 0);
1758 int ocfs2_rw_lock(struct inode *inode, int write)
1761 struct ocfs2_lock_res *lockres;
1762 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1764 mlog(0, "inode %llu take %s RW lock\n",
1765 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1766 write ? "EXMODE" : "PRMODE");
1768 if (ocfs2_mount_local(osb))
1771 lockres = &OCFS2_I(inode)->ip_rw_lockres;
1773 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
1775 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
1782 int ocfs2_try_rw_lock(struct inode *inode, int write)
1785 struct ocfs2_lock_res *lockres;
1786 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1788 mlog(0, "inode %llu try to take %s RW lock\n",
1789 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1790 write ? "EXMODE" : "PRMODE");
1792 if (ocfs2_mount_local(osb))
1795 lockres = &OCFS2_I(inode)->ip_rw_lockres;
1797 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
1799 status = ocfs2_cluster_lock(osb, lockres, level, DLM_LKF_NOQUEUE, 0);
1803 void ocfs2_rw_unlock(struct inode *inode, int write)
1805 int level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
1806 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_rw_lockres;
1807 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1809 mlog(0, "inode %llu drop %s RW lock\n",
1810 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1811 write ? "EXMODE" : "PRMODE");
1813 if (!ocfs2_mount_local(osb))
1814 ocfs2_cluster_unlock(osb, lockres, level);
1818 * ocfs2_open_lock always get PR mode lock.
1820 int ocfs2_open_lock(struct inode *inode)
1823 struct ocfs2_lock_res *lockres;
1824 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1826 mlog(0, "inode %llu take PRMODE open lock\n",
1827 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1829 if (ocfs2_is_hard_readonly(osb) || ocfs2_mount_local(osb))
1832 lockres = &OCFS2_I(inode)->ip_open_lockres;
1834 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_PR, 0, 0);
1842 int ocfs2_try_open_lock(struct inode *inode, int write)
1844 int status = 0, level;
1845 struct ocfs2_lock_res *lockres;
1846 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1848 mlog(0, "inode %llu try to take %s open lock\n",
1849 (unsigned long long)OCFS2_I(inode)->ip_blkno,
1850 write ? "EXMODE" : "PRMODE");
1852 if (ocfs2_is_hard_readonly(osb)) {
1858 if (ocfs2_mount_local(osb))
1861 lockres = &OCFS2_I(inode)->ip_open_lockres;
1863 level = write ? DLM_LOCK_EX : DLM_LOCK_PR;
1866 * The file system may already holding a PRMODE/EXMODE open lock.
1867 * Since we pass DLM_LKF_NOQUEUE, the request won't block waiting on
1868 * other nodes and the -EAGAIN will indicate to the caller that
1869 * this inode is still in use.
1871 status = ocfs2_cluster_lock(osb, lockres, level, DLM_LKF_NOQUEUE, 0);
1878 * ocfs2_open_unlock unlock PR and EX mode open locks.
1880 void ocfs2_open_unlock(struct inode *inode)
1882 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_open_lockres;
1883 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1885 mlog(0, "inode %llu drop open lock\n",
1886 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1888 if (ocfs2_mount_local(osb))
1891 if(lockres->l_ro_holders)
1892 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_PR);
1893 if(lockres->l_ex_holders)
1894 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
1900 static int ocfs2_flock_handle_signal(struct ocfs2_lock_res *lockres,
1904 struct ocfs2_super *osb = ocfs2_get_lockres_osb(lockres);
1905 unsigned long flags;
1906 struct ocfs2_mask_waiter mw;
1908 ocfs2_init_mask_waiter(&mw);
1911 spin_lock_irqsave(&lockres->l_lock, flags);
1912 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
1913 ret = ocfs2_prepare_cancel_convert(osb, lockres);
1915 spin_unlock_irqrestore(&lockres->l_lock, flags);
1916 ret = ocfs2_cancel_convert(osb, lockres);
1923 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1924 spin_unlock_irqrestore(&lockres->l_lock, flags);
1926 ocfs2_wait_for_mask(&mw);
1932 * We may still have gotten the lock, in which case there's no
1933 * point to restarting the syscall.
1935 if (lockres->l_level == level)
1938 mlog(0, "Cancel returning %d. flags: 0x%lx, level: %d, act: %d\n", ret,
1939 lockres->l_flags, lockres->l_level, lockres->l_action);
1941 spin_unlock_irqrestore(&lockres->l_lock, flags);
1948 * ocfs2_file_lock() and ocfs2_file_unlock() map to a single pair of
1949 * flock() calls. The locking approach this requires is sufficiently
1950 * different from all other cluster lock types that we implement a
1951 * separate path to the "low-level" dlm calls. In particular:
1953 * - No optimization of lock levels is done - we take at exactly
1954 * what's been requested.
1956 * - No lock caching is employed. We immediately downconvert to
1957 * no-lock at unlock time. This also means flock locks never go on
1958 * the blocking list).
1960 * - Since userspace can trivially deadlock itself with flock, we make
1961 * sure to allow cancellation of a misbehaving applications flock()
1964 * - Access to any flock lockres doesn't require concurrency, so we
1965 * can simplify the code by requiring the caller to guarantee
1966 * serialization of dlmglue flock calls.
1968 int ocfs2_file_lock(struct file *file, int ex, int trylock)
1970 int ret, level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
1971 unsigned int lkm_flags = trylock ? DLM_LKF_NOQUEUE : 0;
1972 unsigned long flags;
1973 struct ocfs2_file_private *fp = file->private_data;
1974 struct ocfs2_lock_res *lockres = &fp->fp_flock;
1975 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
1976 struct ocfs2_mask_waiter mw;
1978 ocfs2_init_mask_waiter(&mw);
1980 if ((lockres->l_flags & OCFS2_LOCK_BUSY) ||
1981 (lockres->l_level > DLM_LOCK_NL)) {
1983 "File lock \"%s\" has busy or locked state: flags: 0x%lx, "
1984 "level: %u\n", lockres->l_name, lockres->l_flags,
1989 spin_lock_irqsave(&lockres->l_lock, flags);
1990 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
1991 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
1992 spin_unlock_irqrestore(&lockres->l_lock, flags);
1995 * Get the lock at NLMODE to start - that way we
1996 * can cancel the upconvert request if need be.
1998 ret = ocfs2_lock_create(osb, lockres, DLM_LOCK_NL, 0);
2004 ret = ocfs2_wait_for_mask(&mw);
2009 spin_lock_irqsave(&lockres->l_lock, flags);
2012 lockres->l_action = OCFS2_AST_CONVERT;
2013 lkm_flags |= DLM_LKF_CONVERT;
2014 lockres->l_requested = level;
2015 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
2017 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
2018 spin_unlock_irqrestore(&lockres->l_lock, flags);
2020 ret = ocfs2_dlm_lock(osb->cconn, level, &lockres->l_lksb, lkm_flags,
2021 lockres->l_name, OCFS2_LOCK_ID_MAX_LEN - 1);
2023 if (!trylock || (ret != -EAGAIN)) {
2024 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
2028 ocfs2_recover_from_dlm_error(lockres, 1);
2029 lockres_remove_mask_waiter(lockres, &mw);
2033 ret = ocfs2_wait_for_mask_interruptible(&mw, lockres);
2034 if (ret == -ERESTARTSYS) {
2036 * Userspace can cause deadlock itself with
2037 * flock(). Current behavior locally is to allow the
2038 * deadlock, but abort the system call if a signal is
2039 * received. We follow this example, otherwise a
2040 * poorly written program could sit in kernel until
2043 * Handling this is a bit more complicated for Ocfs2
2044 * though. We can't exit this function with an
2045 * outstanding lock request, so a cancel convert is
2046 * required. We intentionally overwrite 'ret' - if the
2047 * cancel fails and the lock was granted, it's easier
2048 * to just bubble success back up to the user.
2050 ret = ocfs2_flock_handle_signal(lockres, level);
2051 } else if (!ret && (level > lockres->l_level)) {
2052 /* Trylock failed asynchronously */
2059 mlog(0, "Lock: \"%s\" ex: %d, trylock: %d, returns: %d\n",
2060 lockres->l_name, ex, trylock, ret);
2064 void ocfs2_file_unlock(struct file *file)
2068 unsigned long flags;
2069 struct ocfs2_file_private *fp = file->private_data;
2070 struct ocfs2_lock_res *lockres = &fp->fp_flock;
2071 struct ocfs2_super *osb = OCFS2_SB(file->f_mapping->host->i_sb);
2072 struct ocfs2_mask_waiter mw;
2074 ocfs2_init_mask_waiter(&mw);
2076 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED))
2079 if (lockres->l_level == DLM_LOCK_NL)
2082 mlog(0, "Unlock: \"%s\" flags: 0x%lx, level: %d, act: %d\n",
2083 lockres->l_name, lockres->l_flags, lockres->l_level,
2086 spin_lock_irqsave(&lockres->l_lock, flags);
2088 * Fake a blocking ast for the downconvert code.
2090 lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
2091 lockres->l_blocking = DLM_LOCK_EX;
2093 gen = ocfs2_prepare_downconvert(lockres, DLM_LOCK_NL);
2094 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
2095 spin_unlock_irqrestore(&lockres->l_lock, flags);
2097 ret = ocfs2_downconvert_lock(osb, lockres, DLM_LOCK_NL, 0, gen);
2103 ret = ocfs2_wait_for_mask(&mw);
2108 static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
2109 struct ocfs2_lock_res *lockres)
2113 /* If we know that another node is waiting on our lock, kick
2114 * the downconvert thread * pre-emptively when we reach a release
2116 if (lockres->l_flags & OCFS2_LOCK_BLOCKED) {
2117 switch(lockres->l_blocking) {
2119 if (!lockres->l_ex_holders && !lockres->l_ro_holders)
2123 if (!lockres->l_ex_holders)
2132 ocfs2_wake_downconvert_thread(osb);
2135 #define OCFS2_SEC_BITS 34
2136 #define OCFS2_SEC_SHIFT (64 - 34)
2137 #define OCFS2_NSEC_MASK ((1ULL << OCFS2_SEC_SHIFT) - 1)
2139 /* LVB only has room for 64 bits of time here so we pack it for
2141 static u64 ocfs2_pack_timespec(struct timespec64 *spec)
2144 u64 sec = clamp_t(time64_t, spec->tv_sec, 0, 0x3ffffffffull);
2145 u32 nsec = spec->tv_nsec;
2147 res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK);
2152 /* Call this with the lockres locked. I am reasonably sure we don't
2153 * need ip_lock in this function as anyone who would be changing those
2154 * values is supposed to be blocked in ocfs2_inode_lock right now. */
2155 static void __ocfs2_stuff_meta_lvb(struct inode *inode)
2157 struct ocfs2_inode_info *oi = OCFS2_I(inode);
2158 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
2159 struct ocfs2_meta_lvb *lvb;
2161 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2164 * Invalidate the LVB of a deleted inode - this way other
2165 * nodes are forced to go to disk and discover the new inode
2168 if (oi->ip_flags & OCFS2_INODE_DELETED) {
2169 lvb->lvb_version = 0;
2173 lvb->lvb_version = OCFS2_LVB_VERSION;
2174 lvb->lvb_isize = cpu_to_be64(i_size_read(inode));
2175 lvb->lvb_iclusters = cpu_to_be32(oi->ip_clusters);
2176 lvb->lvb_iuid = cpu_to_be32(i_uid_read(inode));
2177 lvb->lvb_igid = cpu_to_be32(i_gid_read(inode));
2178 lvb->lvb_imode = cpu_to_be16(inode->i_mode);
2179 lvb->lvb_inlink = cpu_to_be16(inode->i_nlink);
2180 lvb->lvb_iatime_packed =
2181 cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime));
2182 lvb->lvb_ictime_packed =
2183 cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime));
2184 lvb->lvb_imtime_packed =
2185 cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime));
2186 lvb->lvb_iattr = cpu_to_be32(oi->ip_attr);
2187 lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features);
2188 lvb->lvb_igeneration = cpu_to_be32(inode->i_generation);
2191 mlog_meta_lvb(0, lockres);
2194 static void ocfs2_unpack_timespec(struct timespec64 *spec,
2197 spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT;
2198 spec->tv_nsec = packed_time & OCFS2_NSEC_MASK;
2201 static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
2203 struct ocfs2_inode_info *oi = OCFS2_I(inode);
2204 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
2205 struct ocfs2_meta_lvb *lvb;
2207 mlog_meta_lvb(0, lockres);
2209 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2211 /* We're safe here without the lockres lock... */
2212 spin_lock(&oi->ip_lock);
2213 oi->ip_clusters = be32_to_cpu(lvb->lvb_iclusters);
2214 i_size_write(inode, be64_to_cpu(lvb->lvb_isize));
2216 oi->ip_attr = be32_to_cpu(lvb->lvb_iattr);
2217 oi->ip_dyn_features = be16_to_cpu(lvb->lvb_idynfeatures);
2218 ocfs2_set_inode_flags(inode);
2220 /* fast-symlinks are a special case */
2221 if (S_ISLNK(inode->i_mode) && !oi->ip_clusters)
2222 inode->i_blocks = 0;
2224 inode->i_blocks = ocfs2_inode_sector_count(inode);
2226 i_uid_write(inode, be32_to_cpu(lvb->lvb_iuid));
2227 i_gid_write(inode, be32_to_cpu(lvb->lvb_igid));
2228 inode->i_mode = be16_to_cpu(lvb->lvb_imode);
2229 set_nlink(inode, be16_to_cpu(lvb->lvb_inlink));
2230 ocfs2_unpack_timespec(&inode->i_atime,
2231 be64_to_cpu(lvb->lvb_iatime_packed));
2232 ocfs2_unpack_timespec(&inode->i_mtime,
2233 be64_to_cpu(lvb->lvb_imtime_packed));
2234 ocfs2_unpack_timespec(&inode->i_ctime,
2235 be64_to_cpu(lvb->lvb_ictime_packed));
2236 spin_unlock(&oi->ip_lock);
2239 static inline int ocfs2_meta_lvb_is_trustable(struct inode *inode,
2240 struct ocfs2_lock_res *lockres)
2242 struct ocfs2_meta_lvb *lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2244 if (ocfs2_dlm_lvb_valid(&lockres->l_lksb)
2245 && lvb->lvb_version == OCFS2_LVB_VERSION
2246 && be32_to_cpu(lvb->lvb_igeneration) == inode->i_generation)
2251 /* Determine whether a lock resource needs to be refreshed, and
2252 * arbitrate who gets to refresh it.
2254 * 0 means no refresh needed.
2256 * > 0 means you need to refresh this and you MUST call
2257 * ocfs2_complete_lock_res_refresh afterwards. */
2258 static int ocfs2_should_refresh_lock_res(struct ocfs2_lock_res *lockres)
2260 unsigned long flags;
2264 spin_lock_irqsave(&lockres->l_lock, flags);
2265 if (!(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH)) {
2266 spin_unlock_irqrestore(&lockres->l_lock, flags);
2270 if (lockres->l_flags & OCFS2_LOCK_REFRESHING) {
2271 spin_unlock_irqrestore(&lockres->l_lock, flags);
2273 ocfs2_wait_on_refreshing_lock(lockres);
2277 /* Ok, I'll be the one to refresh this lock. */
2278 lockres_or_flags(lockres, OCFS2_LOCK_REFRESHING);
2279 spin_unlock_irqrestore(&lockres->l_lock, flags);
2283 mlog(0, "status %d\n", status);
2287 /* If status is non zero, I'll mark it as not being in refresh
2288 * anymroe, but i won't clear the needs refresh flag. */
2289 static inline void ocfs2_complete_lock_res_refresh(struct ocfs2_lock_res *lockres,
2292 unsigned long flags;
2294 spin_lock_irqsave(&lockres->l_lock, flags);
2295 lockres_clear_flags(lockres, OCFS2_LOCK_REFRESHING);
2297 lockres_clear_flags(lockres, OCFS2_LOCK_NEEDS_REFRESH);
2298 spin_unlock_irqrestore(&lockres->l_lock, flags);
2300 wake_up(&lockres->l_event);
2303 /* may or may not return a bh if it went to disk. */
2304 static int ocfs2_inode_lock_update(struct inode *inode,
2305 struct buffer_head **bh)
2308 struct ocfs2_inode_info *oi = OCFS2_I(inode);
2309 struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
2310 struct ocfs2_dinode *fe;
2311 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2313 if (ocfs2_mount_local(osb))
2316 spin_lock(&oi->ip_lock);
2317 if (oi->ip_flags & OCFS2_INODE_DELETED) {
2318 mlog(0, "Orphaned inode %llu was deleted while we "
2319 "were waiting on a lock. ip_flags = 0x%x\n",
2320 (unsigned long long)oi->ip_blkno, oi->ip_flags);
2321 spin_unlock(&oi->ip_lock);
2325 spin_unlock(&oi->ip_lock);
2327 if (!ocfs2_should_refresh_lock_res(lockres))
2330 /* This will discard any caching information we might have had
2331 * for the inode metadata. */
2332 ocfs2_metadata_cache_purge(INODE_CACHE(inode));
2334 ocfs2_extent_map_trunc(inode, 0);
2336 if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {
2337 mlog(0, "Trusting LVB on inode %llu\n",
2338 (unsigned long long)oi->ip_blkno);
2339 ocfs2_refresh_inode_from_lvb(inode);
2341 /* Boo, we have to go to disk. */
2342 /* read bh, cast, ocfs2_refresh_inode */
2343 status = ocfs2_read_inode_block(inode, bh);
2348 fe = (struct ocfs2_dinode *) (*bh)->b_data;
2350 /* This is a good chance to make sure we're not
2351 * locking an invalid object. ocfs2_read_inode_block()
2352 * already checked that the inode block is sane.
2354 * We bug on a stale inode here because we checked
2355 * above whether it was wiped from disk. The wiping
2356 * node provides a guarantee that we receive that
2357 * message and can mark the inode before dropping any
2358 * locks associated with it. */
2359 mlog_bug_on_msg(inode->i_generation !=
2360 le32_to_cpu(fe->i_generation),
2361 "Invalid dinode %llu disk generation: %u "
2362 "inode->i_generation: %u\n",
2363 (unsigned long long)oi->ip_blkno,
2364 le32_to_cpu(fe->i_generation),
2365 inode->i_generation);
2366 mlog_bug_on_msg(le64_to_cpu(fe->i_dtime) ||
2367 !(fe->i_flags & cpu_to_le32(OCFS2_VALID_FL)),
2368 "Stale dinode %llu dtime: %llu flags: 0x%x\n",
2369 (unsigned long long)oi->ip_blkno,
2370 (unsigned long long)le64_to_cpu(fe->i_dtime),
2371 le32_to_cpu(fe->i_flags));
2373 ocfs2_refresh_inode(inode, fe);
2374 ocfs2_track_lock_refresh(lockres);
2379 ocfs2_complete_lock_res_refresh(lockres, status);
2384 static int ocfs2_assign_bh(struct inode *inode,
2385 struct buffer_head **ret_bh,
2386 struct buffer_head *passed_bh)
2391 /* Ok, the update went to disk for us, use the
2393 *ret_bh = passed_bh;
2399 status = ocfs2_read_inode_block(inode, ret_bh);
2407 * returns < 0 error if the callback will never be called, otherwise
2408 * the result of the lock will be communicated via the callback.
2410 int ocfs2_inode_lock_full_nested(struct inode *inode,
2411 struct buffer_head **ret_bh,
2416 int status, level, acquired;
2418 struct ocfs2_lock_res *lockres = NULL;
2419 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2420 struct buffer_head *local_bh = NULL;
2422 mlog(0, "inode %llu, take %s META lock\n",
2423 (unsigned long long)OCFS2_I(inode)->ip_blkno,
2424 ex ? "EXMODE" : "PRMODE");
2428 /* We'll allow faking a readonly metadata lock for
2430 if (ocfs2_is_hard_readonly(osb)) {
2436 if ((arg_flags & OCFS2_META_LOCK_GETBH) ||
2437 ocfs2_mount_local(osb))
2440 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
2441 ocfs2_wait_for_recovery(osb);
2443 lockres = &OCFS2_I(inode)->ip_inode_lockres;
2444 level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2446 if (arg_flags & OCFS2_META_LOCK_NOQUEUE)
2447 dlm_flags |= DLM_LKF_NOQUEUE;
2449 status = __ocfs2_cluster_lock(osb, lockres, level, dlm_flags,
2450 arg_flags, subclass, _RET_IP_);
2452 if (status != -EAGAIN)
2457 /* Notify the error cleanup path to drop the cluster lock. */
2460 /* We wait twice because a node may have died while we were in
2461 * the lower dlm layers. The second time though, we've
2462 * committed to owning this lock so we don't allow signals to
2463 * abort the operation. */
2464 if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
2465 ocfs2_wait_for_recovery(osb);
2469 * We only see this flag if we're being called from
2470 * ocfs2_read_locked_inode(). It means we're locking an inode
2471 * which hasn't been populated yet, so clear the refresh flag
2472 * and let the caller handle it.
2474 if (inode->i_state & I_NEW) {
2477 ocfs2_complete_lock_res_refresh(lockres, 0);
2481 /* This is fun. The caller may want a bh back, or it may
2482 * not. ocfs2_inode_lock_update definitely wants one in, but
2483 * may or may not read one, depending on what's in the
2484 * LVB. The result of all of this is that we've *only* gone to
2485 * disk if we have to, so the complexity is worthwhile. */
2486 status = ocfs2_inode_lock_update(inode, &local_bh);
2488 if (status != -ENOENT)
2494 status = ocfs2_assign_bh(inode, ret_bh, local_bh);
2503 if (ret_bh && (*ret_bh)) {
2508 ocfs2_inode_unlock(inode, ex);
2516 * This is working around a lock inversion between tasks acquiring DLM
2517 * locks while holding a page lock and the downconvert thread which
2518 * blocks dlm lock acquiry while acquiring page locks.
2520 * ** These _with_page variantes are only intended to be called from aop
2521 * methods that hold page locks and return a very specific *positive* error
2522 * code that aop methods pass up to the VFS -- test for errors with != 0. **
2524 * The DLM is called such that it returns -EAGAIN if it would have
2525 * blocked waiting for the downconvert thread. In that case we unlock
2526 * our page so the downconvert thread can make progress. Once we've
2527 * done this we have to return AOP_TRUNCATED_PAGE so the aop method
2528 * that called us can bubble that back up into the VFS who will then
2529 * immediately retry the aop call.
2531 int ocfs2_inode_lock_with_page(struct inode *inode,
2532 struct buffer_head **ret_bh,
2538 ret = ocfs2_inode_lock_full(inode, ret_bh, ex, OCFS2_LOCK_NONBLOCK);
2539 if (ret == -EAGAIN) {
2542 * If we can't get inode lock immediately, we should not return
2543 * directly here, since this will lead to a softlockup problem.
2544 * The method is to get a blocking lock and immediately unlock
2545 * before returning, this can avoid CPU resource waste due to
2546 * lots of retries, and benefits fairness in getting lock.
2548 if (ocfs2_inode_lock(inode, ret_bh, ex) == 0)
2549 ocfs2_inode_unlock(inode, ex);
2550 ret = AOP_TRUNCATED_PAGE;
2556 int ocfs2_inode_lock_atime(struct inode *inode,
2557 struct vfsmount *vfsmnt,
2558 int *level, int wait)
2563 ret = ocfs2_inode_lock(inode, NULL, 0);
2565 ret = ocfs2_try_inode_lock(inode, NULL, 0);
2574 * If we should update atime, we will get EX lock,
2575 * otherwise we just get PR lock.
2577 if (ocfs2_should_update_atime(inode, vfsmnt)) {
2578 struct buffer_head *bh = NULL;
2580 ocfs2_inode_unlock(inode, 0);
2582 ret = ocfs2_inode_lock(inode, &bh, 1);
2584 ret = ocfs2_try_inode_lock(inode, &bh, 1);
2592 if (ocfs2_should_update_atime(inode, vfsmnt))
2593 ocfs2_update_inode_atime(inode, bh);
2601 void ocfs2_inode_unlock(struct inode *inode,
2604 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2605 struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_inode_lockres;
2606 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2608 mlog(0, "inode %llu drop %s META lock\n",
2609 (unsigned long long)OCFS2_I(inode)->ip_blkno,
2610 ex ? "EXMODE" : "PRMODE");
2612 if (!ocfs2_is_hard_readonly(osb) &&
2613 !ocfs2_mount_local(osb))
2614 ocfs2_cluster_unlock(osb, lockres, level);
2618 * This _tracker variantes are introduced to deal with the recursive cluster
2619 * locking issue. The idea is to keep track of a lock holder on the stack of
2620 * the current process. If there's a lock holder on the stack, we know the
2621 * task context is already protected by cluster locking. Currently, they're
2622 * used in some VFS entry routines.
2624 * return < 0 on error, return == 0 if there's no lock holder on the stack
2625 * before this call, return == 1 if this call would be a recursive locking.
2626 * return == -1 if this lock attempt will cause an upgrade which is forbidden.
2628 * When taking lock levels into account,we face some different situations.
2630 * 1. no lock is held
2631 * In this case, just lock the inode as requested and return 0
2633 * 2. We are holding a lock
2634 * For this situation, things diverges into several cases
2636 * wanted holding what to do
2637 * ex ex see 2.1 below
2638 * ex pr see 2.2 below
2639 * pr ex see 2.1 below
2640 * pr pr see 2.1 below
2642 * 2.1 lock level that is been held is compatible
2643 * with the wanted level, so no lock action will be tacken.
2645 * 2.2 Otherwise, an upgrade is needed, but it is forbidden.
2647 * Reason why upgrade within a process is forbidden is that
2648 * lock upgrade may cause dead lock. The following illustrates
2651 * thread on node1 thread on node2
2652 * ocfs2_inode_lock_tracker(ex=0)
2654 * <====== ocfs2_inode_lock_tracker(ex=1)
2656 * ocfs2_inode_lock_tracker(ex=1)
2658 int ocfs2_inode_lock_tracker(struct inode *inode,
2659 struct buffer_head **ret_bh,
2661 struct ocfs2_lock_holder *oh)
2664 struct ocfs2_lock_res *lockres;
2665 struct ocfs2_lock_holder *tmp_oh;
2666 struct pid *pid = task_pid(current);
2669 lockres = &OCFS2_I(inode)->ip_inode_lockres;
2670 tmp_oh = ocfs2_pid_holder(lockres, pid);
2674 * This corresponds to the case 1.
2675 * We haven't got any lock before.
2677 status = ocfs2_inode_lock_full(inode, ret_bh, ex, 0);
2679 if (status != -ENOENT)
2685 ocfs2_add_holder(lockres, oh);
2689 if (unlikely(ex && !tmp_oh->oh_ex)) {
2691 * case 2.2 upgrade may cause dead lock, forbid it.
2693 mlog(ML_ERROR, "Recursive locking is not permitted to "
2694 "upgrade to EX level from PR level.\n");
2700 * case 2.1 OCFS2_META_LOCK_GETBH flag make ocfs2_inode_lock_full.
2701 * ignore the lock level and just update it.
2704 status = ocfs2_inode_lock_full(inode, ret_bh, ex,
2705 OCFS2_META_LOCK_GETBH);
2707 if (status != -ENOENT)
2712 return tmp_oh ? 1 : 0;
2715 void ocfs2_inode_unlock_tracker(struct inode *inode,
2717 struct ocfs2_lock_holder *oh,
2720 struct ocfs2_lock_res *lockres;
2722 lockres = &OCFS2_I(inode)->ip_inode_lockres;
2723 /* had_lock means that the currect process already takes the cluster
2725 * If had_lock is 1, we have nothing to do here.
2726 * If had_lock is 0, we will release the lock.
2729 ocfs2_inode_unlock(inode, oh->oh_ex);
2730 ocfs2_remove_holder(lockres, oh);
2734 int ocfs2_orphan_scan_lock(struct ocfs2_super *osb, u32 *seqno)
2736 struct ocfs2_lock_res *lockres;
2737 struct ocfs2_orphan_scan_lvb *lvb;
2740 if (ocfs2_is_hard_readonly(osb))
2743 if (ocfs2_mount_local(osb))
2746 lockres = &osb->osb_orphan_scan.os_lockres;
2747 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_EX, 0, 0);
2751 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2752 if (ocfs2_dlm_lvb_valid(&lockres->l_lksb) &&
2753 lvb->lvb_version == OCFS2_ORPHAN_LVB_VERSION)
2754 *seqno = be32_to_cpu(lvb->lvb_os_seqno);
2756 *seqno = osb->osb_orphan_scan.os_seqno + 1;
2761 void ocfs2_orphan_scan_unlock(struct ocfs2_super *osb, u32 seqno)
2763 struct ocfs2_lock_res *lockres;
2764 struct ocfs2_orphan_scan_lvb *lvb;
2766 if (!ocfs2_is_hard_readonly(osb) && !ocfs2_mount_local(osb)) {
2767 lockres = &osb->osb_orphan_scan.os_lockres;
2768 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2769 lvb->lvb_version = OCFS2_ORPHAN_LVB_VERSION;
2770 lvb->lvb_os_seqno = cpu_to_be32(seqno);
2771 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
2775 int ocfs2_super_lock(struct ocfs2_super *osb,
2779 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2780 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
2782 if (ocfs2_is_hard_readonly(osb))
2785 if (ocfs2_mount_local(osb))
2788 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
2794 /* The super block lock path is really in the best position to
2795 * know when resources covered by the lock need to be
2796 * refreshed, so we do it here. Of course, making sense of
2797 * everything is up to the caller :) */
2798 status = ocfs2_should_refresh_lock_res(lockres);
2800 status = ocfs2_refresh_slot_info(osb);
2802 ocfs2_complete_lock_res_refresh(lockres, status);
2805 ocfs2_cluster_unlock(osb, lockres, level);
2808 ocfs2_track_lock_refresh(lockres);
2814 void ocfs2_super_unlock(struct ocfs2_super *osb,
2817 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2818 struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
2820 if (!ocfs2_mount_local(osb))
2821 ocfs2_cluster_unlock(osb, lockres, level);
2824 int ocfs2_rename_lock(struct ocfs2_super *osb)
2827 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2829 if (ocfs2_is_hard_readonly(osb))
2832 if (ocfs2_mount_local(osb))
2835 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_EX, 0, 0);
2842 void ocfs2_rename_unlock(struct ocfs2_super *osb)
2844 struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
2846 if (!ocfs2_mount_local(osb))
2847 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
2850 int ocfs2_nfs_sync_lock(struct ocfs2_super *osb, int ex)
2853 struct ocfs2_lock_res *lockres = &osb->osb_nfs_sync_lockres;
2855 if (ocfs2_is_hard_readonly(osb))
2858 if (ocfs2_mount_local(osb))
2861 status = ocfs2_cluster_lock(osb, lockres, ex ? LKM_EXMODE : LKM_PRMODE,
2864 mlog(ML_ERROR, "lock on nfs sync lock failed %d\n", status);
2869 void ocfs2_nfs_sync_unlock(struct ocfs2_super *osb, int ex)
2871 struct ocfs2_lock_res *lockres = &osb->osb_nfs_sync_lockres;
2873 if (!ocfs2_mount_local(osb))
2874 ocfs2_cluster_unlock(osb, lockres,
2875 ex ? LKM_EXMODE : LKM_PRMODE);
2878 int ocfs2_trim_fs_lock(struct ocfs2_super *osb,
2879 struct ocfs2_trim_fs_info *info, int trylock)
2882 struct ocfs2_trim_fs_lvb *lvb;
2883 struct ocfs2_lock_res *lockres = &osb->osb_trim_fs_lockres;
2888 if (ocfs2_is_hard_readonly(osb))
2891 if (ocfs2_mount_local(osb))
2894 status = ocfs2_cluster_lock(osb, lockres, DLM_LOCK_EX,
2895 trylock ? DLM_LKF_NOQUEUE : 0, 0);
2897 if (status != -EAGAIN)
2903 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2904 if (ocfs2_dlm_lvb_valid(&lockres->l_lksb) &&
2905 lvb->lvb_version == OCFS2_TRIMFS_LVB_VERSION) {
2907 info->tf_success = lvb->lvb_success;
2908 info->tf_nodenum = be32_to_cpu(lvb->lvb_nodenum);
2909 info->tf_start = be64_to_cpu(lvb->lvb_start);
2910 info->tf_len = be64_to_cpu(lvb->lvb_len);
2911 info->tf_minlen = be64_to_cpu(lvb->lvb_minlen);
2912 info->tf_trimlen = be64_to_cpu(lvb->lvb_trimlen);
2919 void ocfs2_trim_fs_unlock(struct ocfs2_super *osb,
2920 struct ocfs2_trim_fs_info *info)
2922 struct ocfs2_trim_fs_lvb *lvb;
2923 struct ocfs2_lock_res *lockres = &osb->osb_trim_fs_lockres;
2925 if (ocfs2_mount_local(osb))
2929 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
2930 lvb->lvb_version = OCFS2_TRIMFS_LVB_VERSION;
2931 lvb->lvb_success = info->tf_success;
2932 lvb->lvb_nodenum = cpu_to_be32(info->tf_nodenum);
2933 lvb->lvb_start = cpu_to_be64(info->tf_start);
2934 lvb->lvb_len = cpu_to_be64(info->tf_len);
2935 lvb->lvb_minlen = cpu_to_be64(info->tf_minlen);
2936 lvb->lvb_trimlen = cpu_to_be64(info->tf_trimlen);
2939 ocfs2_cluster_unlock(osb, lockres, DLM_LOCK_EX);
2942 int ocfs2_dentry_lock(struct dentry *dentry, int ex)
2945 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2946 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2947 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2951 if (ocfs2_is_hard_readonly(osb)) {
2957 if (ocfs2_mount_local(osb))
2960 ret = ocfs2_cluster_lock(osb, &dl->dl_lockres, level, 0, 0);
2967 void ocfs2_dentry_unlock(struct dentry *dentry, int ex)
2969 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
2970 struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
2971 struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
2973 if (!ocfs2_is_hard_readonly(osb) && !ocfs2_mount_local(osb))
2974 ocfs2_cluster_unlock(osb, &dl->dl_lockres, level);
2977 /* Reference counting of the dlm debug structure. We want this because
2978 * open references on the debug inodes can live on after a mount, so
2979 * we can't rely on the ocfs2_super to always exist. */
2980 static void ocfs2_dlm_debug_free(struct kref *kref)
2982 struct ocfs2_dlm_debug *dlm_debug;
2984 dlm_debug = container_of(kref, struct ocfs2_dlm_debug, d_refcnt);
2989 void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug)
2992 kref_put(&dlm_debug->d_refcnt, ocfs2_dlm_debug_free);
2995 static void ocfs2_get_dlm_debug(struct ocfs2_dlm_debug *debug)
2997 kref_get(&debug->d_refcnt);
3000 struct ocfs2_dlm_debug *ocfs2_new_dlm_debug(void)
3002 struct ocfs2_dlm_debug *dlm_debug;
3004 dlm_debug = kmalloc(sizeof(struct ocfs2_dlm_debug), GFP_KERNEL);
3006 mlog_errno(-ENOMEM);
3010 kref_init(&dlm_debug->d_refcnt);
3011 INIT_LIST_HEAD(&dlm_debug->d_lockres_tracking);
3012 dlm_debug->d_filter_secs = 0;
3017 /* Access to this is arbitrated for us via seq_file->sem. */
3018 struct ocfs2_dlm_seq_priv {
3019 struct ocfs2_dlm_debug *p_dlm_debug;
3020 struct ocfs2_lock_res p_iter_res;
3021 struct ocfs2_lock_res p_tmp_res;
3024 static struct ocfs2_lock_res *ocfs2_dlm_next_res(struct ocfs2_lock_res *start,
3025 struct ocfs2_dlm_seq_priv *priv)
3027 struct ocfs2_lock_res *iter, *ret = NULL;
3028 struct ocfs2_dlm_debug *dlm_debug = priv->p_dlm_debug;
3030 assert_spin_locked(&ocfs2_dlm_tracking_lock);
3032 list_for_each_entry(iter, &start->l_debug_list, l_debug_list) {
3033 /* discover the head of the list */
3034 if (&iter->l_debug_list == &dlm_debug->d_lockres_tracking) {
3035 mlog(0, "End of list found, %p\n", ret);
3039 /* We track our "dummy" iteration lockres' by a NULL
3041 if (iter->l_ops != NULL) {
3050 static void *ocfs2_dlm_seq_start(struct seq_file *m, loff_t *pos)
3052 struct ocfs2_dlm_seq_priv *priv = m->private;
3053 struct ocfs2_lock_res *iter;
3055 spin_lock(&ocfs2_dlm_tracking_lock);
3056 iter = ocfs2_dlm_next_res(&priv->p_iter_res, priv);
3058 /* Since lockres' have the lifetime of their container
3059 * (which can be inodes, ocfs2_supers, etc) we want to
3060 * copy this out to a temporary lockres while still
3061 * under the spinlock. Obviously after this we can't
3062 * trust any pointers on the copy returned, but that's
3063 * ok as the information we want isn't typically held
3065 priv->p_tmp_res = *iter;
3066 iter = &priv->p_tmp_res;
3068 spin_unlock(&ocfs2_dlm_tracking_lock);
3073 static void ocfs2_dlm_seq_stop(struct seq_file *m, void *v)
3077 static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
3079 struct ocfs2_dlm_seq_priv *priv = m->private;
3080 struct ocfs2_lock_res *iter = v;
3081 struct ocfs2_lock_res *dummy = &priv->p_iter_res;
3083 spin_lock(&ocfs2_dlm_tracking_lock);
3084 iter = ocfs2_dlm_next_res(iter, priv);
3085 list_del_init(&dummy->l_debug_list);
3087 list_add(&dummy->l_debug_list, &iter->l_debug_list);
3088 priv->p_tmp_res = *iter;
3089 iter = &priv->p_tmp_res;
3091 spin_unlock(&ocfs2_dlm_tracking_lock);
3097 * Version is used by debugfs.ocfs2 to determine the format being used
3100 * - Lock stats printed
3102 * - Max time in lock stats is in usecs (instead of nsecs)
3104 * - Add last pr/ex unlock times and first lock wait time in usecs
3106 #define OCFS2_DLM_DEBUG_STR_VERSION 4
3107 static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
3111 struct ocfs2_lock_res *lockres = v;
3112 #ifdef CONFIG_OCFS2_FS_STATS
3114 struct ocfs2_dlm_debug *dlm_debug =
3115 ((struct ocfs2_dlm_seq_priv *)m->private)->p_dlm_debug;
3121 #ifdef CONFIG_OCFS2_FS_STATS
3122 if (!lockres->l_lock_wait && dlm_debug->d_filter_secs) {
3123 now = ktime_to_us(ktime_get_real());
3124 if (lockres->l_lock_prmode.ls_last >
3125 lockres->l_lock_exmode.ls_last)
3126 last = lockres->l_lock_prmode.ls_last;
3128 last = lockres->l_lock_exmode.ls_last;
3130 * Use d_filter_secs field to filter lock resources dump,
3131 * the default d_filter_secs(0) value filters nothing,
3132 * otherwise, only dump the last N seconds active lock
3135 if (div_u64(now - last, 1000000) > dlm_debug->d_filter_secs)
3140 seq_printf(m, "0x%x\t", OCFS2_DLM_DEBUG_STR_VERSION);
3142 if (lockres->l_type == OCFS2_LOCK_TYPE_DENTRY)
3143 seq_printf(m, "%.*s%08x\t", OCFS2_DENTRY_LOCK_INO_START - 1,
3145 (unsigned int)ocfs2_get_dentry_lock_ino(lockres));
3147 seq_printf(m, "%.*s\t", OCFS2_LOCK_ID_MAX_LEN, lockres->l_name);
3149 seq_printf(m, "%d\t"
3160 lockres->l_unlock_action,
3161 lockres->l_ro_holders,
3162 lockres->l_ex_holders,
3163 lockres->l_requested,
3164 lockres->l_blocking);
3166 /* Dump the raw LVB */
3167 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
3168 for(i = 0; i < DLM_LVB_LEN; i++)
3169 seq_printf(m, "0x%x\t", lvb[i]);
3171 #ifdef CONFIG_OCFS2_FS_STATS
3172 # define lock_num_prmode(_l) ((_l)->l_lock_prmode.ls_gets)
3173 # define lock_num_exmode(_l) ((_l)->l_lock_exmode.ls_gets)
3174 # define lock_num_prmode_failed(_l) ((_l)->l_lock_prmode.ls_fail)
3175 # define lock_num_exmode_failed(_l) ((_l)->l_lock_exmode.ls_fail)
3176 # define lock_total_prmode(_l) ((_l)->l_lock_prmode.ls_total)
3177 # define lock_total_exmode(_l) ((_l)->l_lock_exmode.ls_total)
3178 # define lock_max_prmode(_l) ((_l)->l_lock_prmode.ls_max)
3179 # define lock_max_exmode(_l) ((_l)->l_lock_exmode.ls_max)
3180 # define lock_refresh(_l) ((_l)->l_lock_refresh)
3181 # define lock_last_prmode(_l) ((_l)->l_lock_prmode.ls_last)
3182 # define lock_last_exmode(_l) ((_l)->l_lock_exmode.ls_last)
3183 # define lock_wait(_l) ((_l)->l_lock_wait)
3185 # define lock_num_prmode(_l) (0)
3186 # define lock_num_exmode(_l) (0)
3187 # define lock_num_prmode_failed(_l) (0)
3188 # define lock_num_exmode_failed(_l) (0)
3189 # define lock_total_prmode(_l) (0ULL)
3190 # define lock_total_exmode(_l) (0ULL)
3191 # define lock_max_prmode(_l) (0)
3192 # define lock_max_exmode(_l) (0)
3193 # define lock_refresh(_l) (0)
3194 # define lock_last_prmode(_l) (0ULL)
3195 # define lock_last_exmode(_l) (0ULL)
3196 # define lock_wait(_l) (0ULL)
3198 /* The following seq_print was added in version 2 of this output */
3199 seq_printf(m, "%u\t"
3211 lock_num_prmode(lockres),
3212 lock_num_exmode(lockres),
3213 lock_num_prmode_failed(lockres),
3214 lock_num_exmode_failed(lockres),
3215 lock_total_prmode(lockres),
3216 lock_total_exmode(lockres),
3217 lock_max_prmode(lockres),
3218 lock_max_exmode(lockres),
3219 lock_refresh(lockres),
3220 lock_last_prmode(lockres),
3221 lock_last_exmode(lockres),
3222 lock_wait(lockres));
3225 seq_printf(m, "\n");
3229 static const struct seq_operations ocfs2_dlm_seq_ops = {
3230 .start = ocfs2_dlm_seq_start,
3231 .stop = ocfs2_dlm_seq_stop,
3232 .next = ocfs2_dlm_seq_next,
3233 .show = ocfs2_dlm_seq_show,
3236 static int ocfs2_dlm_debug_release(struct inode *inode, struct file *file)
3238 struct seq_file *seq = file->private_data;
3239 struct ocfs2_dlm_seq_priv *priv = seq->private;
3240 struct ocfs2_lock_res *res = &priv->p_iter_res;
3242 ocfs2_remove_lockres_tracking(res);
3243 ocfs2_put_dlm_debug(priv->p_dlm_debug);
3244 return seq_release_private(inode, file);
3247 static int ocfs2_dlm_debug_open(struct inode *inode, struct file *file)
3249 struct ocfs2_dlm_seq_priv *priv;
3250 struct ocfs2_super *osb;
3252 priv = __seq_open_private(file, &ocfs2_dlm_seq_ops, sizeof(*priv));
3254 mlog_errno(-ENOMEM);
3258 osb = inode->i_private;
3259 ocfs2_get_dlm_debug(osb->osb_dlm_debug);
3260 priv->p_dlm_debug = osb->osb_dlm_debug;
3261 INIT_LIST_HEAD(&priv->p_iter_res.l_debug_list);
3263 ocfs2_add_lockres_tracking(&priv->p_iter_res,
3269 static const struct file_operations ocfs2_dlm_debug_fops = {
3270 .open = ocfs2_dlm_debug_open,
3271 .release = ocfs2_dlm_debug_release,
3273 .llseek = seq_lseek,
3276 static void ocfs2_dlm_init_debug(struct ocfs2_super *osb)
3278 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
3280 debugfs_create_file("locking_state", S_IFREG|S_IRUSR,
3281 osb->osb_debug_root, osb, &ocfs2_dlm_debug_fops);
3283 debugfs_create_u32("locking_filter", 0600, osb->osb_debug_root,
3284 &dlm_debug->d_filter_secs);
3287 static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)
3289 struct ocfs2_dlm_debug *dlm_debug = osb->osb_dlm_debug;
3292 ocfs2_put_dlm_debug(dlm_debug);
3295 int ocfs2_dlm_init(struct ocfs2_super *osb)
3298 struct ocfs2_cluster_connection *conn = NULL;
3300 if (ocfs2_mount_local(osb)) {
3305 ocfs2_dlm_init_debug(osb);
3307 /* launch downconvert thread */
3308 osb->dc_task = kthread_run(ocfs2_downconvert_thread, osb, "ocfs2dc-%s",
3310 if (IS_ERR(osb->dc_task)) {
3311 status = PTR_ERR(osb->dc_task);
3312 osb->dc_task = NULL;
3317 /* for now, uuid == domain */
3318 status = ocfs2_cluster_connect(osb->osb_cluster_stack,
3319 osb->osb_cluster_name,
3320 strlen(osb->osb_cluster_name),
3322 strlen(osb->uuid_str),
3323 &lproto, ocfs2_do_node_down, osb,
3330 status = ocfs2_cluster_this_node(conn, &osb->node_num);
3334 "could not find this host's node number\n");
3335 ocfs2_cluster_disconnect(conn, 0);
3340 ocfs2_super_lock_res_init(&osb->osb_super_lockres, osb);
3341 ocfs2_rename_lock_res_init(&osb->osb_rename_lockres, osb);
3342 ocfs2_nfs_sync_lock_res_init(&osb->osb_nfs_sync_lockres, osb);
3343 ocfs2_orphan_scan_lock_res_init(&osb->osb_orphan_scan.os_lockres, osb);
3348 ocfs2_dlm_shutdown_debug(osb);
3350 kthread_stop(osb->dc_task);
3356 void ocfs2_dlm_shutdown(struct ocfs2_super *osb,
3359 ocfs2_drop_osb_locks(osb);
3362 * Now that we have dropped all locks and ocfs2_dismount_volume()
3363 * has disabled recovery, the DLM won't be talking to us. It's
3364 * safe to tear things down before disconnecting the cluster.
3368 kthread_stop(osb->dc_task);
3369 osb->dc_task = NULL;
3372 ocfs2_lock_res_free(&osb->osb_super_lockres);
3373 ocfs2_lock_res_free(&osb->osb_rename_lockres);
3374 ocfs2_lock_res_free(&osb->osb_nfs_sync_lockres);
3375 ocfs2_lock_res_free(&osb->osb_orphan_scan.os_lockres);
3377 ocfs2_cluster_disconnect(osb->cconn, hangup_pending);
3380 ocfs2_dlm_shutdown_debug(osb);
3383 static int ocfs2_drop_lock(struct ocfs2_super *osb,
3384 struct ocfs2_lock_res *lockres)
3387 unsigned long flags;
3390 /* We didn't get anywhere near actually using this lockres. */
3391 if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED))
3394 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
3395 lkm_flags |= DLM_LKF_VALBLK;
3397 spin_lock_irqsave(&lockres->l_lock, flags);
3399 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_FREEING),
3400 "lockres %s, flags 0x%lx\n",
3401 lockres->l_name, lockres->l_flags);
3403 while (lockres->l_flags & OCFS2_LOCK_BUSY) {
3404 mlog(0, "waiting on busy lock \"%s\": flags = %lx, action = "
3405 "%u, unlock_action = %u\n",
3406 lockres->l_name, lockres->l_flags, lockres->l_action,
3407 lockres->l_unlock_action);
3409 spin_unlock_irqrestore(&lockres->l_lock, flags);
3411 /* XXX: Today we just wait on any busy
3412 * locks... Perhaps we need to cancel converts in the
3414 ocfs2_wait_on_busy_lock(lockres);
3416 spin_lock_irqsave(&lockres->l_lock, flags);
3419 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
3420 if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
3421 lockres->l_level == DLM_LOCK_EX &&
3422 !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
3423 lockres->l_ops->set_lvb(lockres);
3426 if (lockres->l_flags & OCFS2_LOCK_BUSY)
3427 mlog(ML_ERROR, "destroying busy lock: \"%s\"\n",
3429 if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
3430 mlog(0, "destroying blocked lock: \"%s\"\n", lockres->l_name);
3432 if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED)) {
3433 spin_unlock_irqrestore(&lockres->l_lock, flags);
3437 lockres_clear_flags(lockres, OCFS2_LOCK_ATTACHED);
3439 /* make sure we never get here while waiting for an ast to
3441 BUG_ON(lockres->l_action != OCFS2_AST_INVALID);
3443 /* is this necessary? */
3444 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
3445 lockres->l_unlock_action = OCFS2_UNLOCK_DROP_LOCK;
3446 spin_unlock_irqrestore(&lockres->l_lock, flags);
3448 mlog(0, "lock %s\n", lockres->l_name);
3450 ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb, lkm_flags);
3452 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
3453 mlog(ML_ERROR, "lockres flags: %lu\n", lockres->l_flags);
3454 ocfs2_dlm_dump_lksb(&lockres->l_lksb);
3457 mlog(0, "lock %s, successful return from ocfs2_dlm_unlock\n",
3460 ocfs2_wait_on_busy_lock(lockres);
3465 static void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
3466 struct ocfs2_lock_res *lockres);
3468 /* Mark the lockres as being dropped. It will no longer be
3469 * queued if blocking, but we still may have to wait on it
3470 * being dequeued from the downconvert thread before we can consider
3473 * You can *not* attempt to call cluster_lock on this lockres anymore. */
3474 void ocfs2_mark_lockres_freeing(struct ocfs2_super *osb,
3475 struct ocfs2_lock_res *lockres)
3478 struct ocfs2_mask_waiter mw;
3479 unsigned long flags, flags2;
3481 ocfs2_init_mask_waiter(&mw);
3483 spin_lock_irqsave(&lockres->l_lock, flags);
3484 lockres->l_flags |= OCFS2_LOCK_FREEING;
3485 if (lockres->l_flags & OCFS2_LOCK_QUEUED && current == osb->dc_task) {
3487 * We know the downconvert is queued but not in progress
3488 * because we are the downconvert thread and processing
3489 * different lock. So we can just remove the lock from the
3490 * queue. This is not only an optimization but also a way
3491 * to avoid the following deadlock:
3492 * ocfs2_dentry_post_unlock()
3493 * ocfs2_dentry_lock_put()
3494 * ocfs2_drop_dentry_lock()
3496 * ocfs2_evict_inode()
3497 * ocfs2_clear_inode()
3498 * ocfs2_mark_lockres_freeing()
3499 * ... blocks waiting for OCFS2_LOCK_QUEUED
3500 * since we are the downconvert thread which
3501 * should clear the flag.
3503 spin_unlock_irqrestore(&lockres->l_lock, flags);
3504 spin_lock_irqsave(&osb->dc_task_lock, flags2);
3505 list_del_init(&lockres->l_blocked_list);
3506 osb->blocked_lock_count--;
3507 spin_unlock_irqrestore(&osb->dc_task_lock, flags2);
3509 * Warn if we recurse into another post_unlock call. Strictly
3510 * speaking it isn't a problem but we need to be careful if
3511 * that happens (stack overflow, deadlocks, ...) so warn if
3512 * ocfs2 grows a path for which this can happen.
3514 WARN_ON_ONCE(lockres->l_ops->post_unlock);
3515 /* Since the lock is freeing we don't do much in the fn below */
3516 ocfs2_process_blocked_lock(osb, lockres);
3519 while (lockres->l_flags & OCFS2_LOCK_QUEUED) {
3520 lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_QUEUED, 0);
3521 spin_unlock_irqrestore(&lockres->l_lock, flags);
3523 mlog(0, "Waiting on lockres %s\n", lockres->l_name);
3525 status = ocfs2_wait_for_mask(&mw);
3529 spin_lock_irqsave(&lockres->l_lock, flags);
3531 spin_unlock_irqrestore(&lockres->l_lock, flags);
3534 void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
3535 struct ocfs2_lock_res *lockres)
3539 ocfs2_mark_lockres_freeing(osb, lockres);
3540 ret = ocfs2_drop_lock(osb, lockres);
3545 static void ocfs2_drop_osb_locks(struct ocfs2_super *osb)
3547 ocfs2_simple_drop_lockres(osb, &osb->osb_super_lockres);
3548 ocfs2_simple_drop_lockres(osb, &osb->osb_rename_lockres);
3549 ocfs2_simple_drop_lockres(osb, &osb->osb_nfs_sync_lockres);
3550 ocfs2_simple_drop_lockres(osb, &osb->osb_orphan_scan.os_lockres);
3553 int ocfs2_drop_inode_locks(struct inode *inode)
3557 /* No need to call ocfs2_mark_lockres_freeing here -
3558 * ocfs2_clear_inode has done it for us. */
3560 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
3561 &OCFS2_I(inode)->ip_open_lockres);
3567 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
3568 &OCFS2_I(inode)->ip_inode_lockres);
3571 if (err < 0 && !status)
3574 err = ocfs2_drop_lock(OCFS2_SB(inode->i_sb),
3575 &OCFS2_I(inode)->ip_rw_lockres);
3578 if (err < 0 && !status)
3584 static unsigned int ocfs2_prepare_downconvert(struct ocfs2_lock_res *lockres,
3587 assert_spin_locked(&lockres->l_lock);
3589 BUG_ON(lockres->l_blocking <= DLM_LOCK_NL);
3591 if (lockres->l_level <= new_level) {
3592 mlog(ML_ERROR, "lockres %s, lvl %d <= %d, blcklst %d, mask %d, "
3593 "type %d, flags 0x%lx, hold %d %d, act %d %d, req %d, "
3594 "block %d, pgen %d\n", lockres->l_name, lockres->l_level,
3595 new_level, list_empty(&lockres->l_blocked_list),
3596 list_empty(&lockres->l_mask_waiters), lockres->l_type,
3597 lockres->l_flags, lockres->l_ro_holders,
3598 lockres->l_ex_holders, lockres->l_action,
3599 lockres->l_unlock_action, lockres->l_requested,
3600 lockres->l_blocking, lockres->l_pending_gen);
3604 mlog(ML_BASTS, "lockres %s, level %d => %d, blocking %d\n",
3605 lockres->l_name, lockres->l_level, new_level, lockres->l_blocking);
3607 lockres->l_action = OCFS2_AST_DOWNCONVERT;
3608 lockres->l_requested = new_level;
3609 lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
3610 return lockres_set_pending(lockres);
3613 static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
3614 struct ocfs2_lock_res *lockres,
3617 unsigned int generation)
3620 u32 dlm_flags = DLM_LKF_CONVERT;
3622 mlog(ML_BASTS, "lockres %s, level %d => %d\n", lockres->l_name,
3623 lockres->l_level, new_level);
3626 * On DLM_LKF_VALBLK, fsdlm behaves differently with o2cb. It always
3627 * expects DLM_LKF_VALBLK being set if the LKB has LVB, so that
3628 * we can recover correctly from node failure. Otherwise, we may get
3629 * invalid LVB in LKB, but without DLM_SBF_VALNOTVALID being set.
3631 if (ocfs2_userspace_stack(osb) &&
3632 lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
3636 dlm_flags |= DLM_LKF_VALBLK;
3638 ret = ocfs2_dlm_lock(osb->cconn,
3643 OCFS2_LOCK_ID_MAX_LEN - 1);
3644 lockres_clear_pending(lockres, generation, osb);
3646 ocfs2_log_dlm_error("ocfs2_dlm_lock", ret, lockres);
3647 ocfs2_recover_from_dlm_error(lockres, 1);
3656 /* returns 1 when the caller should unlock and call ocfs2_dlm_unlock */
3657 static int ocfs2_prepare_cancel_convert(struct ocfs2_super *osb,
3658 struct ocfs2_lock_res *lockres)
3660 assert_spin_locked(&lockres->l_lock);
3662 if (lockres->l_unlock_action == OCFS2_UNLOCK_CANCEL_CONVERT) {
3663 /* If we're already trying to cancel a lock conversion
3664 * then just drop the spinlock and allow the caller to
3665 * requeue this lock. */
3666 mlog(ML_BASTS, "lockres %s, skip convert\n", lockres->l_name);
3670 /* were we in a convert when we got the bast fire? */
3671 BUG_ON(lockres->l_action != OCFS2_AST_CONVERT &&
3672 lockres->l_action != OCFS2_AST_DOWNCONVERT);
3673 /* set things up for the unlockast to know to just
3674 * clear out the ast_action and unset busy, etc. */
3675 lockres->l_unlock_action = OCFS2_UNLOCK_CANCEL_CONVERT;
3677 mlog_bug_on_msg(!(lockres->l_flags & OCFS2_LOCK_BUSY),
3678 "lock %s, invalid flags: 0x%lx\n",
3679 lockres->l_name, lockres->l_flags);
3681 mlog(ML_BASTS, "lockres %s\n", lockres->l_name);
3686 static int ocfs2_cancel_convert(struct ocfs2_super *osb,
3687 struct ocfs2_lock_res *lockres)
3691 ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb,
3694 ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
3695 ocfs2_recover_from_dlm_error(lockres, 0);
3698 mlog(ML_BASTS, "lockres %s\n", lockres->l_name);
3703 static int ocfs2_unblock_lock(struct ocfs2_super *osb,
3704 struct ocfs2_lock_res *lockres,
3705 struct ocfs2_unblock_ctl *ctl)
3707 unsigned long flags;
3715 spin_lock_irqsave(&lockres->l_lock, flags);
3719 * Is it still blocking? If not, we have no more work to do.
3721 if (!(lockres->l_flags & OCFS2_LOCK_BLOCKED)) {
3722 BUG_ON(lockres->l_blocking != DLM_LOCK_NL);
3723 spin_unlock_irqrestore(&lockres->l_lock, flags);
3728 if (lockres->l_flags & OCFS2_LOCK_BUSY) {
3730 * This is a *big* race. The OCFS2_LOCK_PENDING flag
3731 * exists entirely for one reason - another thread has set
3732 * OCFS2_LOCK_BUSY, but has *NOT* yet called dlm_lock().
3734 * If we do ocfs2_cancel_convert() before the other thread
3735 * calls dlm_lock(), our cancel will do nothing. We will
3736 * get no ast, and we will have no way of knowing the
3737 * cancel failed. Meanwhile, the other thread will call
3738 * into dlm_lock() and wait...forever.
3740 * Why forever? Because another node has asked for the
3741 * lock first; that's why we're here in unblock_lock().
3743 * The solution is OCFS2_LOCK_PENDING. When PENDING is
3744 * set, we just requeue the unblock. Only when the other
3745 * thread has called dlm_lock() and cleared PENDING will
3746 * we then cancel their request.
3748 * All callers of dlm_lock() must set OCFS2_DLM_PENDING
3749 * at the same time they set OCFS2_DLM_BUSY. They must
3750 * clear OCFS2_DLM_PENDING after dlm_lock() returns.
3752 if (lockres->l_flags & OCFS2_LOCK_PENDING) {
3753 mlog(ML_BASTS, "lockres %s, ReQ: Pending\n",
3759 ret = ocfs2_prepare_cancel_convert(osb, lockres);
3760 spin_unlock_irqrestore(&lockres->l_lock, flags);
3762 ret = ocfs2_cancel_convert(osb, lockres);
3770 * This prevents livelocks. OCFS2_LOCK_UPCONVERT_FINISHING flag is
3771 * set when the ast is received for an upconvert just before the
3772 * OCFS2_LOCK_BUSY flag is cleared. Now if the fs received a bast
3773 * on the heels of the ast, we want to delay the downconvert just
3774 * enough to allow the up requestor to do its task. Because this
3775 * lock is in the blocked queue, the lock will be downconverted
3776 * as soon as the requestor is done with the lock.
3778 if (lockres->l_flags & OCFS2_LOCK_UPCONVERT_FINISHING)
3782 * How can we block and yet be at NL? We were trying to upconvert
3783 * from NL and got canceled. The code comes back here, and now
3784 * we notice and clear BLOCKING.
3786 if (lockres->l_level == DLM_LOCK_NL) {
3787 BUG_ON(lockres->l_ex_holders || lockres->l_ro_holders);
3788 mlog(ML_BASTS, "lockres %s, Aborting dc\n", lockres->l_name);
3789 lockres->l_blocking = DLM_LOCK_NL;
3790 lockres_clear_flags(lockres, OCFS2_LOCK_BLOCKED);
3791 spin_unlock_irqrestore(&lockres->l_lock, flags);
3795 /* if we're blocking an exclusive and we have *any* holders,
3797 if ((lockres->l_blocking == DLM_LOCK_EX)
3798 && (lockres->l_ex_holders || lockres->l_ro_holders)) {
3799 mlog(ML_BASTS, "lockres %s, ReQ: EX/PR Holders %u,%u\n",
3800 lockres->l_name, lockres->l_ex_holders,
3801 lockres->l_ro_holders);
3805 /* If it's a PR we're blocking, then only
3806 * requeue if we've got any EX holders */
3807 if (lockres->l_blocking == DLM_LOCK_PR &&
3808 lockres->l_ex_holders) {
3809 mlog(ML_BASTS, "lockres %s, ReQ: EX Holders %u\n",
3810 lockres->l_name, lockres->l_ex_holders);
3815 * Can we get a lock in this state if the holder counts are
3816 * zero? The meta data unblock code used to check this.
3818 if ((lockres->l_ops->flags & LOCK_TYPE_REQUIRES_REFRESH)
3819 && (lockres->l_flags & OCFS2_LOCK_REFRESHING)) {
3820 mlog(ML_BASTS, "lockres %s, ReQ: Lock Refreshing\n",
3825 new_level = ocfs2_highest_compat_lock_level(lockres->l_blocking);
3827 if (lockres->l_ops->check_downconvert
3828 && !lockres->l_ops->check_downconvert(lockres, new_level)) {
3829 mlog(ML_BASTS, "lockres %s, ReQ: Checkpointing\n",
3834 /* If we get here, then we know that there are no more
3835 * incompatible holders (and anyone asking for an incompatible
3836 * lock is blocked). We can now downconvert the lock */
3837 if (!lockres->l_ops->downconvert_worker)
3840 /* Some lockres types want to do a bit of work before
3841 * downconverting a lock. Allow that here. The worker function
3842 * may sleep, so we save off a copy of what we're blocking as
3843 * it may change while we're not holding the spin lock. */
3844 blocking = lockres->l_blocking;
3845 level = lockres->l_level;
3846 spin_unlock_irqrestore(&lockres->l_lock, flags);
3848 ctl->unblock_action = lockres->l_ops->downconvert_worker(lockres, blocking);
3850 if (ctl->unblock_action == UNBLOCK_STOP_POST) {
3851 mlog(ML_BASTS, "lockres %s, UNBLOCK_STOP_POST\n",
3856 spin_lock_irqsave(&lockres->l_lock, flags);
3857 if ((blocking != lockres->l_blocking) || (level != lockres->l_level)) {
3858 /* If this changed underneath us, then we can't drop
3860 mlog(ML_BASTS, "lockres %s, block=%d:%d, level=%d:%d, "
3861 "Recheck\n", lockres->l_name, blocking,
3862 lockres->l_blocking, level, lockres->l_level);
3869 if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
3870 if (lockres->l_level == DLM_LOCK_EX)
3874 * We only set the lvb if the lock has been fully
3875 * refreshed - otherwise we risk setting stale
3876 * data. Otherwise, there's no need to actually clear
3877 * out the lvb here as it's value is still valid.
3879 if (set_lvb && !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
3880 lockres->l_ops->set_lvb(lockres);
3883 gen = ocfs2_prepare_downconvert(lockres, new_level);
3884 spin_unlock_irqrestore(&lockres->l_lock, flags);
3885 ret = ocfs2_downconvert_lock(osb, lockres, new_level, set_lvb,
3894 spin_unlock_irqrestore(&lockres->l_lock, flags);
3900 static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
3903 struct inode *inode;
3904 struct address_space *mapping;
3905 struct ocfs2_inode_info *oi;
3907 inode = ocfs2_lock_res_inode(lockres);
3908 mapping = inode->i_mapping;
3910 if (S_ISDIR(inode->i_mode)) {
3911 oi = OCFS2_I(inode);
3912 oi->ip_dir_lock_gen++;
3913 mlog(0, "generation: %u\n", oi->ip_dir_lock_gen);
3917 if (!S_ISREG(inode->i_mode))
3921 * We need this before the filemap_fdatawrite() so that it can
3922 * transfer the dirty bit from the PTE to the
3923 * page. Unfortunately this means that even for EX->PR
3924 * downconverts, we'll lose our mappings and have to build
3927 unmap_mapping_range(mapping, 0, 0, 0);
3929 if (filemap_fdatawrite(mapping)) {
3930 mlog(ML_ERROR, "Could not sync inode %llu for downconvert!",
3931 (unsigned long long)OCFS2_I(inode)->ip_blkno);
3933 sync_mapping_buffers(mapping);
3934 if (blocking == DLM_LOCK_EX) {
3935 truncate_inode_pages(mapping, 0);
3937 /* We only need to wait on the I/O if we're not also
3938 * truncating pages because truncate_inode_pages waits
3939 * for us above. We don't truncate pages if we're
3940 * blocking anything < EXMODE because we want to keep
3941 * them around in that case. */
3942 filemap_fdatawait(mapping);
3945 forget_all_cached_acls(inode);
3948 return UNBLOCK_CONTINUE;
3951 static int ocfs2_ci_checkpointed(struct ocfs2_caching_info *ci,
3952 struct ocfs2_lock_res *lockres,
3955 int checkpointed = ocfs2_ci_fully_checkpointed(ci);
3957 BUG_ON(new_level != DLM_LOCK_NL && new_level != DLM_LOCK_PR);
3958 BUG_ON(lockres->l_level != DLM_LOCK_EX && !checkpointed);
3963 ocfs2_start_checkpoint(OCFS2_SB(ocfs2_metadata_cache_get_super(ci)));
3967 static int ocfs2_check_meta_downconvert(struct ocfs2_lock_res *lockres,
3970 struct inode *inode = ocfs2_lock_res_inode(lockres);
3972 return ocfs2_ci_checkpointed(INODE_CACHE(inode), lockres, new_level);
3975 static void ocfs2_set_meta_lvb(struct ocfs2_lock_res *lockres)
3977 struct inode *inode = ocfs2_lock_res_inode(lockres);
3979 __ocfs2_stuff_meta_lvb(inode);
3983 * Does the final reference drop on our dentry lock. Right now this
3984 * happens in the downconvert thread, but we could choose to simplify the
3985 * dlmglue API and push these off to the ocfs2_wq in the future.
3987 static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
3988 struct ocfs2_lock_res *lockres)
3990 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
3991 ocfs2_dentry_lock_put(osb, dl);
3995 * d_delete() matching dentries before the lock downconvert.
3997 * At this point, any process waiting to destroy the
3998 * dentry_lock due to last ref count is stopped by the
3999 * OCFS2_LOCK_QUEUED flag.
4001 * We have two potential problems
4003 * 1) If we do the last reference drop on our dentry_lock (via dput)
4004 * we'll wind up in ocfs2_release_dentry_lock(), waiting on
4005 * the downconvert to finish. Instead we take an elevated
4006 * reference and push the drop until after we've completed our
4007 * unblock processing.
4009 * 2) There might be another process with a final reference,
4010 * waiting on us to finish processing. If this is the case, we
4011 * detect it and exit out - there's no more dentries anyway.
4013 static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
4016 struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
4017 struct ocfs2_inode_info *oi = OCFS2_I(dl->dl_inode);
4018 struct dentry *dentry;
4019 unsigned long flags;
4023 * This node is blocking another node from getting a read
4024 * lock. This happens when we've renamed within a
4025 * directory. We've forced the other nodes to d_delete(), but
4026 * we never actually dropped our lock because it's still
4027 * valid. The downconvert code will retain a PR for this node,
4028 * so there's no further work to do.
4030 if (blocking == DLM_LOCK_PR)
4031 return UNBLOCK_CONTINUE;
4034 * Mark this inode as potentially orphaned. The code in
4035 * ocfs2_delete_inode() will figure out whether it actually
4036 * needs to be freed or not.
4038 spin_lock(&oi->ip_lock);
4039 oi->ip_flags |= OCFS2_INODE_MAYBE_ORPHANED;
4040 spin_unlock(&oi->ip_lock);
4043 * Yuck. We need to make sure however that the check of
4044 * OCFS2_LOCK_FREEING and the extra reference are atomic with
4045 * respect to a reference decrement or the setting of that
4048 spin_lock_irqsave(&lockres->l_lock, flags);
4049 spin_lock(&dentry_attach_lock);
4050 if (!(lockres->l_flags & OCFS2_LOCK_FREEING)
4055 spin_unlock(&dentry_attach_lock);
4056 spin_unlock_irqrestore(&lockres->l_lock, flags);
4058 mlog(0, "extra_ref = %d\n", extra_ref);
4061 * We have a process waiting on us in ocfs2_dentry_iput(),
4062 * which means we can't have any more outstanding
4063 * aliases. There's no need to do any more work.
4066 return UNBLOCK_CONTINUE;
4068 spin_lock(&dentry_attach_lock);
4070 dentry = ocfs2_find_local_alias(dl->dl_inode,
4071 dl->dl_parent_blkno, 1);
4074 spin_unlock(&dentry_attach_lock);
4076 if (S_ISDIR(dl->dl_inode->i_mode))
4077 shrink_dcache_parent(dentry);
4079 mlog(0, "d_delete(%pd);\n", dentry);
4082 * The following dcache calls may do an
4083 * iput(). Normally we don't want that from the
4084 * downconverting thread, but in this case it's ok
4085 * because the requesting node already has an
4086 * exclusive lock on the inode, so it can't be queued
4087 * for a downconvert.
4092 spin_lock(&dentry_attach_lock);
4094 spin_unlock(&dentry_attach_lock);
4097 * If we are the last holder of this dentry lock, there is no
4098 * reason to downconvert so skip straight to the unlock.
4100 if (dl->dl_count == 1)
4101 return UNBLOCK_STOP_POST;
4103 return UNBLOCK_CONTINUE_POST;
4106 static int ocfs2_check_refcount_downconvert(struct ocfs2_lock_res *lockres,
4109 struct ocfs2_refcount_tree *tree =
4110 ocfs2_lock_res_refcount_tree(lockres);
4112 return ocfs2_ci_checkpointed(&tree->rf_ci, lockres, new_level);
4115 static int ocfs2_refcount_convert_worker(struct ocfs2_lock_res *lockres,
4118 struct ocfs2_refcount_tree *tree =
4119 ocfs2_lock_res_refcount_tree(lockres);
4121 ocfs2_metadata_cache_purge(&tree->rf_ci);
4123 return UNBLOCK_CONTINUE;
4126 static void ocfs2_set_qinfo_lvb(struct ocfs2_lock_res *lockres)
4128 struct ocfs2_qinfo_lvb *lvb;
4129 struct ocfs2_mem_dqinfo *oinfo = ocfs2_lock_res_qinfo(lockres);
4130 struct mem_dqinfo *info = sb_dqinfo(oinfo->dqi_gi.dqi_sb,
4131 oinfo->dqi_gi.dqi_type);
4133 lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
4134 lvb->lvb_version = OCFS2_QINFO_LVB_VERSION;
4135 lvb->lvb_bgrace = cpu_to_be32(info->dqi_bgrace);
4136 lvb->lvb_igrace = cpu_to_be32(info->dqi_igrace);
4137 lvb->lvb_syncms = cpu_to_be32(oinfo->dqi_syncms);
4138 lvb->lvb_blocks = cpu_to_be32(oinfo->dqi_gi.dqi_blocks);
4139 lvb->lvb_free_blk = cpu_to_be32(oinfo->dqi_gi.dqi_free_blk);
4140 lvb->lvb_free_entry = cpu_to_be32(oinfo->dqi_gi.dqi_free_entry);
4143 void ocfs2_qinfo_unlock(struct ocfs2_mem_dqinfo *oinfo, int ex)
4145 struct ocfs2_lock_res *lockres = &oinfo->dqi_gqlock;
4146 struct ocfs2_super *osb = OCFS2_SB(oinfo->dqi_gi.dqi_sb);
4147 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
4149 if (!ocfs2_is_hard_readonly(osb) && !ocfs2_mount_local(osb))
4150 ocfs2_cluster_unlock(osb, lockres, level);
4153 static int ocfs2_refresh_qinfo(struct ocfs2_mem_dqinfo *oinfo)
4155 struct mem_dqinfo *info = sb_dqinfo(oinfo->dqi_gi.dqi_sb,
4156 oinfo->dqi_gi.dqi_type);
4157 struct ocfs2_lock_res *lockres = &oinfo->dqi_gqlock;
4158 struct ocfs2_qinfo_lvb *lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
4159 struct buffer_head *bh = NULL;
4160 struct ocfs2_global_disk_dqinfo *gdinfo;
4163 if (ocfs2_dlm_lvb_valid(&lockres->l_lksb) &&
4164 lvb->lvb_version == OCFS2_QINFO_LVB_VERSION) {
4165 info->dqi_bgrace = be32_to_cpu(lvb->lvb_bgrace);
4166 info->dqi_igrace = be32_to_cpu(lvb->lvb_igrace);
4167 oinfo->dqi_syncms = be32_to_cpu(lvb->lvb_syncms);
4168 oinfo->dqi_gi.dqi_blocks = be32_to_cpu(lvb->lvb_blocks);
4169 oinfo->dqi_gi.dqi_free_blk = be32_to_cpu(lvb->lvb_free_blk);
4170 oinfo->dqi_gi.dqi_free_entry =
4171 be32_to_cpu(lvb->lvb_free_entry);
4173 status = ocfs2_read_quota_phys_block(oinfo->dqi_gqinode,
4174 oinfo->dqi_giblk, &bh);
4179 gdinfo = (struct ocfs2_global_disk_dqinfo *)
4180 (bh->b_data + OCFS2_GLOBAL_INFO_OFF);
4181 info->dqi_bgrace = le32_to_cpu(gdinfo->dqi_bgrace);
4182 info->dqi_igrace = le32_to_cpu(gdinfo->dqi_igrace);
4183 oinfo->dqi_syncms = le32_to_cpu(gdinfo->dqi_syncms);
4184 oinfo->dqi_gi.dqi_blocks = le32_to_cpu(gdinfo->dqi_blocks);
4185 oinfo->dqi_gi.dqi_free_blk = le32_to_cpu(gdinfo->dqi_free_blk);
4186 oinfo->dqi_gi.dqi_free_entry =
4187 le32_to_cpu(gdinfo->dqi_free_entry);
4189 ocfs2_track_lock_refresh(lockres);
4196 /* Lock quota info, this function expects at least shared lock on the quota file
4197 * so that we can safely refresh quota info from disk. */
4198 int ocfs2_qinfo_lock(struct ocfs2_mem_dqinfo *oinfo, int ex)
4200 struct ocfs2_lock_res *lockres = &oinfo->dqi_gqlock;
4201 struct ocfs2_super *osb = OCFS2_SB(oinfo->dqi_gi.dqi_sb);
4202 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
4205 /* On RO devices, locking really isn't needed... */
4206 if (ocfs2_is_hard_readonly(osb)) {
4211 if (ocfs2_mount_local(osb))
4214 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
4219 if (!ocfs2_should_refresh_lock_res(lockres))
4221 /* OK, we have the lock but we need to refresh the quota info */
4222 status = ocfs2_refresh_qinfo(oinfo);
4224 ocfs2_qinfo_unlock(oinfo, ex);
4225 ocfs2_complete_lock_res_refresh(lockres, status);
4230 int ocfs2_refcount_lock(struct ocfs2_refcount_tree *ref_tree, int ex)
4233 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
4234 struct ocfs2_lock_res *lockres = &ref_tree->rf_lockres;
4235 struct ocfs2_super *osb = lockres->l_priv;
4238 if (ocfs2_is_hard_readonly(osb))
4241 if (ocfs2_mount_local(osb))
4244 status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
4251 void ocfs2_refcount_unlock(struct ocfs2_refcount_tree *ref_tree, int ex)
4253 int level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
4254 struct ocfs2_lock_res *lockres = &ref_tree->rf_lockres;
4255 struct ocfs2_super *osb = lockres->l_priv;
4257 if (!ocfs2_mount_local(osb))
4258 ocfs2_cluster_unlock(osb, lockres, level);
4261 static void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
4262 struct ocfs2_lock_res *lockres)
4265 struct ocfs2_unblock_ctl ctl = {0, 0,};
4266 unsigned long flags;
4268 /* Our reference to the lockres in this function can be
4269 * considered valid until we remove the OCFS2_LOCK_QUEUED
4273 BUG_ON(!lockres->l_ops);
4275 mlog(ML_BASTS, "lockres %s blocked\n", lockres->l_name);
4277 /* Detect whether a lock has been marked as going away while
4278 * the downconvert thread was processing other things. A lock can
4279 * still be marked with OCFS2_LOCK_FREEING after this check,
4280 * but short circuiting here will still save us some
4282 spin_lock_irqsave(&lockres->l_lock, flags);
4283 if (lockres->l_flags & OCFS2_LOCK_FREEING)
4285 spin_unlock_irqrestore(&lockres->l_lock, flags);
4287 status = ocfs2_unblock_lock(osb, lockres, &ctl);
4291 spin_lock_irqsave(&lockres->l_lock, flags);
4293 if (lockres->l_flags & OCFS2_LOCK_FREEING || !ctl.requeue) {
4294 lockres_clear_flags(lockres, OCFS2_LOCK_QUEUED);
4296 ocfs2_schedule_blocked_lock(osb, lockres);
4298 mlog(ML_BASTS, "lockres %s, requeue = %s.\n", lockres->l_name,
4299 ctl.requeue ? "yes" : "no");
4300 spin_unlock_irqrestore(&lockres->l_lock, flags);
4302 if (ctl.unblock_action != UNBLOCK_CONTINUE
4303 && lockres->l_ops->post_unlock)
4304 lockres->l_ops->post_unlock(osb, lockres);
4307 static void ocfs2_schedule_blocked_lock(struct ocfs2_super *osb,
4308 struct ocfs2_lock_res *lockres)
4310 unsigned long flags;
4312 assert_spin_locked(&lockres->l_lock);
4314 if (lockres->l_flags & OCFS2_LOCK_FREEING) {
4315 /* Do not schedule a lock for downconvert when it's on
4316 * the way to destruction - any nodes wanting access
4317 * to the resource will get it soon. */
4318 mlog(ML_BASTS, "lockres %s won't be scheduled: flags 0x%lx\n",
4319 lockres->l_name, lockres->l_flags);
4323 lockres_or_flags(lockres, OCFS2_LOCK_QUEUED);
4325 spin_lock_irqsave(&osb->dc_task_lock, flags);
4326 if (list_empty(&lockres->l_blocked_list)) {
4327 list_add_tail(&lockres->l_blocked_list,
4328 &osb->blocked_lock_list);
4329 osb->blocked_lock_count++;
4331 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4334 static void ocfs2_downconvert_thread_do_work(struct ocfs2_super *osb)
4336 unsigned long processed;
4337 unsigned long flags;
4338 struct ocfs2_lock_res *lockres;
4340 spin_lock_irqsave(&osb->dc_task_lock, flags);
4341 /* grab this early so we know to try again if a state change and
4342 * wake happens part-way through our work */
4343 osb->dc_work_sequence = osb->dc_wake_sequence;
4345 processed = osb->blocked_lock_count;
4347 * blocked lock processing in this loop might call iput which can
4348 * remove items off osb->blocked_lock_list. Downconvert up to
4349 * 'processed' number of locks, but stop short if we had some
4350 * removed in ocfs2_mark_lockres_freeing when downconverting.
4352 while (processed && !list_empty(&osb->blocked_lock_list)) {
4353 lockres = list_entry(osb->blocked_lock_list.next,
4354 struct ocfs2_lock_res, l_blocked_list);
4355 list_del_init(&lockres->l_blocked_list);
4356 osb->blocked_lock_count--;
4357 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4362 ocfs2_process_blocked_lock(osb, lockres);
4364 spin_lock_irqsave(&osb->dc_task_lock, flags);
4366 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4369 static int ocfs2_downconvert_thread_lists_empty(struct ocfs2_super *osb)
4372 unsigned long flags;
4374 spin_lock_irqsave(&osb->dc_task_lock, flags);
4375 if (list_empty(&osb->blocked_lock_list))
4378 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4382 static int ocfs2_downconvert_thread_should_wake(struct ocfs2_super *osb)
4384 int should_wake = 0;
4385 unsigned long flags;
4387 spin_lock_irqsave(&osb->dc_task_lock, flags);
4388 if (osb->dc_work_sequence != osb->dc_wake_sequence)
4390 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4395 static int ocfs2_downconvert_thread(void *arg)
4397 struct ocfs2_super *osb = arg;
4399 /* only quit once we've been asked to stop and there is no more
4401 while (!(kthread_should_stop() &&
4402 ocfs2_downconvert_thread_lists_empty(osb))) {
4404 wait_event_interruptible(osb->dc_event,
4405 ocfs2_downconvert_thread_should_wake(osb) ||
4406 kthread_should_stop());
4408 mlog(0, "downconvert_thread: awoken\n");
4410 ocfs2_downconvert_thread_do_work(osb);
4413 osb->dc_task = NULL;
4417 void ocfs2_wake_downconvert_thread(struct ocfs2_super *osb)
4419 unsigned long flags;
4421 spin_lock_irqsave(&osb->dc_task_lock, flags);
4422 /* make sure the voting thread gets a swipe at whatever changes
4423 * the caller may have made to the voting state */
4424 osb->dc_wake_sequence++;
4425 spin_unlock_irqrestore(&osb->dc_task_lock, flags);
4426 wake_up(&osb->dc_event);