[linux.git] / fs / dlm / ast.c

/******************************************************************************
*******************************************************************************
**
**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
**  Copyright (C) 2004-2010 Red Hat, Inc.  All rights reserved.
**
**  This copyrighted material is made available to anyone wishing to use,
**  modify, copy, or redistribute it subject to the terms and conditions
**  of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/

#include "dlm_internal.h"
#include "lock.h"
#include "user.h"

static uint64_t			dlm_cb_seq;
static spinlock_t		dlm_cb_seq_spin;

static void dlm_dump_lkb_callbacks(struct dlm_lkb *lkb)
{
	int i;

	log_print("last_bast %x %llu flags %x mode %d sb %d %x",
		  lkb->lkb_id,
		  (unsigned long long)lkb->lkb_last_bast.seq,
		  lkb->lkb_last_bast.flags,
		  lkb->lkb_last_bast.mode,
		  lkb->lkb_last_bast.sb_status,
		  lkb->lkb_last_bast.sb_flags);

	log_print("last_cast %x %llu flags %x mode %d sb %d %x",
		  lkb->lkb_id,
		  (unsigned long long)lkb->lkb_last_cast.seq,
		  lkb->lkb_last_cast.flags,
		  lkb->lkb_last_cast.mode,
		  lkb->lkb_last_cast.sb_status,
		  lkb->lkb_last_cast.sb_flags);

	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
		log_print("cb %x %llu flags %x mode %d sb %d %x",
			  lkb->lkb_id,
			  (unsigned long long)lkb->lkb_callbacks[i].seq,
			  lkb->lkb_callbacks[i].flags,
			  lkb->lkb_callbacks[i].mode,
			  lkb->lkb_callbacks[i].sb_status,
			  lkb->lkb_callbacks[i].sb_flags);
	}
}

int dlm_add_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
			 int status, uint32_t sbflags, uint64_t seq)
{
	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
	uint64_t prev_seq;
	int prev_mode;
	int i, rv;

	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
		if (lkb->lkb_callbacks[i].seq)
			continue;

		/*
		 * Suppress some redundant basts here, do more on removal.
		 * Don't even add a bast if the callback just before it
		 * is a bast for the same mode or a more restrictive mode.
		 * (the addional > PR check is needed for PR/CW inversion)
		 */

		if ((i > 0) && (flags & DLM_CB_BAST) &&
		    (lkb->lkb_callbacks[i-1].flags & DLM_CB_BAST)) {

			prev_seq = lkb->lkb_callbacks[i-1].seq;
			prev_mode = lkb->lkb_callbacks[i-1].mode;

			if ((prev_mode == mode) ||
			    (prev_mode > mode && prev_mode > DLM_LOCK_PR)) {

				log_debug(ls, "skip %x add bast %llu mode %d "
					  "for bast %llu mode %d",
					  lkb->lkb_id,
					  (unsigned long long)seq,
					  mode,
					  (unsigned long long)prev_seq,
					  prev_mode);
				rv = 0;
				goto out;
			}
		}

		lkb->lkb_callbacks[i].seq = seq;
		lkb->lkb_callbacks[i].flags = flags;
		lkb->lkb_callbacks[i].mode = mode;
		lkb->lkb_callbacks[i].sb_status = status;
		lkb->lkb_callbacks[i].sb_flags = (sbflags & 0x000000FF);
		rv = 0;
		break;
	}

	if (i == DLM_CALLBACKS_SIZE) {
		log_error(ls, "no callbacks %x %llu flags %x mode %d sb %d %x",
			  lkb->lkb_id, (unsigned long long)seq,
			  flags, mode, status, sbflags);
		dlm_dump_lkb_callbacks(lkb);
		rv = -1;
		goto out;
	}
 out:
	return rv;
}

int dlm_rem_lkb_callback(struct dlm_ls *ls, struct dlm_lkb *lkb,
			 struct dlm_callback *cb, int *resid)
{
	int i, rv;

	*resid = 0;

	if (!lkb->lkb_callbacks[0].seq) {
		rv = -ENOENT;
		goto out;
	}

	/* oldest undelivered cb is callbacks[0] */

	memcpy(cb, &lkb->lkb_callbacks[0], sizeof(struct dlm_callback));
	memset(&lkb->lkb_callbacks[0], 0, sizeof(struct dlm_callback));

	/* shift others down */

	for (i = 1; i < DLM_CALLBACKS_SIZE; i++) {
		if (!lkb->lkb_callbacks[i].seq)
			break;
		memcpy(&lkb->lkb_callbacks[i-1], &lkb->lkb_callbacks[i],
		       sizeof(struct dlm_callback));
		memset(&lkb->lkb_callbacks[i], 0, sizeof(struct dlm_callback));
		(*resid)++;
	}

	/* if cb is a bast, it should be skipped if the blocking mode is
	   compatible with the last granted mode */

	if ((cb->flags & DLM_CB_BAST) && lkb->lkb_last_cast.seq) {
		if (dlm_modes_compat(cb->mode, lkb->lkb_last_cast.mode)) {
			cb->flags |= DLM_CB_SKIP;

			log_debug(ls, "skip %x bast %llu mode %d "
				  "for cast %llu mode %d",
				  lkb->lkb_id,
				  (unsigned long long)cb->seq,
				  cb->mode,
				  (unsigned long long)lkb->lkb_last_cast.seq,
				  lkb->lkb_last_cast.mode);
			rv = 0;
			goto out;
		}
	}

	if (cb->flags & DLM_CB_CAST) {
		memcpy(&lkb->lkb_last_cast, cb, sizeof(struct dlm_callback));
		lkb->lkb_last_cast_time = ktime_get();
	}

	if (cb->flags & DLM_CB_BAST) {
		memcpy(&lkb->lkb_last_bast, cb, sizeof(struct dlm_callback));
		lkb->lkb_last_bast_time = ktime_get();
	}
	rv = 0;
 out:
	return rv;
}

void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
		uint32_t sbflags)
{
	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
	uint64_t new_seq, prev_seq;
	int rv;

	spin_lock(&dlm_cb_seq_spin);
	new_seq = ++dlm_cb_seq;
	spin_unlock(&dlm_cb_seq_spin);

	if (lkb->lkb_flags & DLM_IFL_USER) {
		dlm_user_add_ast(lkb, flags, mode, status, sbflags, new_seq);
		return;
	}

	mutex_lock(&lkb->lkb_cb_mutex);
	prev_seq = lkb->lkb_callbacks[0].seq;

	rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, new_seq);
	if (rv < 0)
		goto out;

	if (!prev_seq) {
		kref_get(&lkb->lkb_ref);

		if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
			mutex_lock(&ls->ls_cb_mutex);
			list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
			mutex_unlock(&ls->ls_cb_mutex);
		} else {
			queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
		}
	}
 out:
	mutex_unlock(&lkb->lkb_cb_mutex);
}

void dlm_callback_work(struct work_struct *work)
{
	struct dlm_lkb *lkb = container_of(work, struct dlm_lkb, lkb_cb_work);
	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
	void (*castfn) (void *astparam);
	void (*bastfn) (void *astparam, int mode);
	struct dlm_callback callbacks[DLM_CALLBACKS_SIZE];
	int i, rv, resid;

	memset(&callbacks, 0, sizeof(callbacks));

	mutex_lock(&lkb->lkb_cb_mutex);
	if (!lkb->lkb_callbacks[0].seq) {
		/* no callback work exists, shouldn't happen */
		log_error(ls, "dlm_callback_work %x no work", lkb->lkb_id);
		dlm_print_lkb(lkb);
		dlm_dump_lkb_callbacks(lkb);
	}

	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
		rv = dlm_rem_lkb_callback(ls, lkb, &callbacks[i], &resid);
		if (rv < 0)
			break;
	}

	if (resid) {
		/* cbs remain, loop should have removed all, shouldn't happen */
		log_error(ls, "dlm_callback_work %x resid %d", lkb->lkb_id,
			  resid);
		dlm_print_lkb(lkb);
		dlm_dump_lkb_callbacks(lkb);
	}
	mutex_unlock(&lkb->lkb_cb_mutex);

	castfn = lkb->lkb_astfn;
	bastfn = lkb->lkb_bastfn;

	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
		if (!callbacks[i].seq)
			break;
		if (callbacks[i].flags & DLM_CB_SKIP) {
			continue;
		} else if (callbacks[i].flags & DLM_CB_BAST) {
			bastfn(lkb->lkb_astparam, callbacks[i].mode);
		} else if (callbacks[i].flags & DLM_CB_CAST) {
			lkb->lkb_lksb->sb_status = callbacks[i].sb_status;
			lkb->lkb_lksb->sb_flags = callbacks[i].sb_flags;
			castfn(lkb->lkb_astparam);
		}
	}

	/* undo kref_get from dlm_add_callback, may cause lkb to be freed */
	dlm_put_lkb(lkb);
}

int dlm_callback_start(struct dlm_ls *ls)
{
	ls->ls_callback_wq = alloc_workqueue("dlm_callback",
					     WQ_UNBOUND |
					     WQ_MEM_RECLAIM |
					     WQ_NON_REENTRANT,
					     0);
	if (!ls->ls_callback_wq) {
		log_print("can't start dlm_callback workqueue");
		return -ENOMEM;
	}
	return 0;
}

void dlm_callback_stop(struct dlm_ls *ls)
{
	if (ls->ls_callback_wq)
		destroy_workqueue(ls->ls_callback_wq);
}

void dlm_callback_suspend(struct dlm_ls *ls)
{
	set_bit(LSFL_CB_DELAY, &ls->ls_flags);

	if (ls->ls_callback_wq)
		flush_workqueue(ls->ls_callback_wq);
}

void dlm_callback_resume(struct dlm_ls *ls)
{
	struct dlm_lkb *lkb, *safe;
	int count = 0;

	clear_bit(LSFL_CB_DELAY, &ls->ls_flags);

	if (!ls->ls_callback_wq)
		return;

	mutex_lock(&ls->ls_cb_mutex);
	list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
		list_del_init(&lkb->lkb_cb_list);
		queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
		count++;
	}
	mutex_unlock(&ls->ls_cb_mutex);

	log_debug(ls, "dlm_callback_resume %d", count);
}
Commit	Line	Data
e7fd4179 DT	1	/******************************************************************************
	2	*******************************************************************************
	3	**
	4	** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
7fe2b319	5	** Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
e7fd4179 DT	6	**
	7	** This copyrighted material is made available to anyone wishing to use,
	8	** modify, copy, or redistribute it subject to the terms and conditions
	9	** of the GNU General Public License v.2.
	10	**
	11	*******************************************************************************
	12	******************************************************************************/
	13
	14	#include "dlm_internal.h"
	15	#include "lock.h"
597d0cae	16	#include "user.h"
e7fd4179	17
23e8e1aa DT	18	static uint64_t dlm_cb_seq;
23e8e1aa DT	19	static spinlock_t dlm_cb_seq_spin;
e7fd4179	20
8304d6f2 DT	21	static void dlm_dump_lkb_callbacks(struct dlm_lkb *lkb)
	22	{
	23	int i;
	24
	25	log_print("last_bast %x %llu flags %x mode %d sb %d %x",
	26	lkb->lkb_id,
	27	(unsigned long long)lkb->lkb_last_bast.seq,
	28	lkb->lkb_last_bast.flags,
	29	lkb->lkb_last_bast.mode,
	30	lkb->lkb_last_bast.sb_status,
	31	lkb->lkb_last_bast.sb_flags);
	32
	33	log_print("last_cast %x %llu flags %x mode %d sb %d %x",
	34	lkb->lkb_id,
	35	(unsigned long long)lkb->lkb_last_cast.seq,
	36	lkb->lkb_last_cast.flags,
	37	lkb->lkb_last_cast.mode,
	38	lkb->lkb_last_cast.sb_status,
	39	lkb->lkb_last_cast.sb_flags);
	40
	41	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
	42	log_print("cb %x %llu flags %x mode %d sb %d %x",
	43	lkb->lkb_id,
	44	(unsigned long long)lkb->lkb_callbacks[i].seq,
	45	lkb->lkb_callbacks[i].flags,
	46	lkb->lkb_callbacks[i].mode,
	47	lkb->lkb_callbacks[i].sb_status,
	48	lkb->lkb_callbacks[i].sb_flags);
	49	}
	50	}
	51
8304d6f2 DT	52	int dlm_add_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
	53	int status, uint32_t sbflags, uint64_t seq)
	54	{
	55	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
	56	uint64_t prev_seq;
	57	int prev_mode;
23e8e1aa	58	int i, rv;
8304d6f2 DT	59
	60	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
	61	if (lkb->lkb_callbacks[i].seq)
	62	continue;
	63
	64	/*
	65	* Suppress some redundant basts here, do more on removal.
	66	* Don't even add a bast if the callback just before it
	67	* is a bast for the same mode or a more restrictive mode.
	68	* (the addional > PR check is needed for PR/CW inversion)
	69	*/
	70
	71	if ((i > 0) && (flags & DLM_CB_BAST) &&
	72	(lkb->lkb_callbacks[i-1].flags & DLM_CB_BAST)) {
	73
	74	prev_seq = lkb->lkb_callbacks[i-1].seq;
	75	prev_mode = lkb->lkb_callbacks[i-1].mode;
	76
	77	if ((prev_mode == mode) \|\|
	78	(prev_mode > mode && prev_mode > DLM_LOCK_PR)) {
	79
	80	log_debug(ls, "skip %x add bast %llu mode %d "
	81	"for bast %llu mode %d",
	82	lkb->lkb_id,
	83	(unsigned long long)seq,
	84	mode,
	85	(unsigned long long)prev_seq,
	86	prev_mode);
23e8e1aa DT	87	rv = 0;
23e8e1aa DT	88	goto out;
8304d6f2 DT	89	}
	90	}
	91
	92	lkb->lkb_callbacks[i].seq = seq;
	93	lkb->lkb_callbacks[i].flags = flags;
	94	lkb->lkb_callbacks[i].mode = mode;
	95	lkb->lkb_callbacks[i].sb_status = status;
	96	lkb->lkb_callbacks[i].sb_flags = (sbflags & 0x000000FF);
23e8e1aa	97	rv = 0;
8304d6f2 DT	98	break;
	99	}
	100
	101	if (i == DLM_CALLBACKS_SIZE) {
	102	log_error(ls, "no callbacks %x %llu flags %x mode %d sb %d %x",
	103	lkb->lkb_id, (unsigned long long)seq,
	104	flags, mode, status, sbflags);
	105	dlm_dump_lkb_callbacks(lkb);
23e8e1aa DT	106	rv = -1;
23e8e1aa DT	107	goto out;
8304d6f2	108	}
23e8e1aa DT	109	out:
23e8e1aa DT	110	return rv;
8304d6f2 DT	111	}
	112
	113	int dlm_rem_lkb_callback(struct dlm_ls ls, struct dlm_lkb lkb,
	114	struct dlm_callback cb, int resid)
e7fd4179	115	{
23e8e1aa	116	int i, rv;
8304d6f2 DT	117
	118	*resid = 0;
	119
23e8e1aa DT	120	if (!lkb->lkb_callbacks[0].seq) {
	121	rv = -ENOENT;
	122	goto out;
	123	}
8304d6f2 DT	124
	125	/* oldest undelivered cb is callbacks[0] */
	126
	127	memcpy(cb, &lkb->lkb_callbacks[0], sizeof(struct dlm_callback));
	128	memset(&lkb->lkb_callbacks[0], 0, sizeof(struct dlm_callback));
	129
	130	/* shift others down */
	131
	132	for (i = 1; i < DLM_CALLBACKS_SIZE; i++) {
	133	if (!lkb->lkb_callbacks[i].seq)
	134	break;
	135	memcpy(&lkb->lkb_callbacks[i-1], &lkb->lkb_callbacks[i],
	136	sizeof(struct dlm_callback));
	137	memset(&lkb->lkb_callbacks[i], 0, sizeof(struct dlm_callback));
	138	(*resid)++;
	139	}
	140
	141	/* if cb is a bast, it should be skipped if the blocking mode is
	142	compatible with the last granted mode */
	143
	144	if ((cb->flags & DLM_CB_BAST) && lkb->lkb_last_cast.seq) {
	145	if (dlm_modes_compat(cb->mode, lkb->lkb_last_cast.mode)) {
	146	cb->flags \|= DLM_CB_SKIP;
	147
	148	log_debug(ls, "skip %x bast %llu mode %d "
	149	"for cast %llu mode %d",
	150	lkb->lkb_id,
	151	(unsigned long long)cb->seq,
	152	cb->mode,
	153	(unsigned long long)lkb->lkb_last_cast.seq,
	154	lkb->lkb_last_cast.mode);
23e8e1aa DT	155	rv = 0;
23e8e1aa DT	156	goto out;
8304d6f2 DT	157	}
	158	}
	159
	160	if (cb->flags & DLM_CB_CAST) {
	161	memcpy(&lkb->lkb_last_cast, cb, sizeof(struct dlm_callback));
	162	lkb->lkb_last_cast_time = ktime_get();
	163	}
	164
	165	if (cb->flags & DLM_CB_BAST) {
	166	memcpy(&lkb->lkb_last_bast, cb, sizeof(struct dlm_callback));
	167	lkb->lkb_last_bast_time = ktime_get();
	168	}
23e8e1aa DT	169	rv = 0;
	170	out:
	171	return rv;
8304d6f2 DT	172	}
8304d6f2 DT	173
23e8e1aa DT	174	void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
23e8e1aa DT	175	uint32_t sbflags)
8304d6f2	176	{
23e8e1aa DT	177	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
23e8e1aa DT	178	uint64_t new_seq, prev_seq;
8304d6f2 DT	179	int rv;
8304d6f2 DT	180
23e8e1aa DT	181	spin_lock(&dlm_cb_seq_spin);
	182	new_seq = ++dlm_cb_seq;
	183	spin_unlock(&dlm_cb_seq_spin);
8304d6f2	184
597d0cae	185	if (lkb->lkb_flags & DLM_IFL_USER) {
23e8e1aa	186	dlm_user_add_ast(lkb, flags, mode, status, sbflags, new_seq);
597d0cae DT	187	return;
	188	}
	189
23e8e1aa DT	190	mutex_lock(&lkb->lkb_cb_mutex);
23e8e1aa DT	191	prev_seq = lkb->lkb_callbacks[0].seq;
8304d6f2	192
23e8e1aa DT	193	rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, new_seq);
	194	if (rv < 0)
	195	goto out;
	196
	197	if (!prev_seq) {
e7fd4179	198	kref_get(&lkb->lkb_ref);
e7fd4179	199
23e8e1aa DT	200	if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
	201	mutex_lock(&ls->ls_cb_mutex);
	202	list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
	203	mutex_unlock(&ls->ls_cb_mutex);
	204	} else {
	205	queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
	206	}
	207	}
	208	out:
	209	mutex_unlock(&lkb->lkb_cb_mutex);
e7fd4179 DT	210	}
e7fd4179 DT	211
23e8e1aa	212	void dlm_callback_work(struct work_struct *work)
e7fd4179	213	{
23e8e1aa DT	214	struct dlm_lkb *lkb = container_of(work, struct dlm_lkb, lkb_cb_work);
23e8e1aa DT	215	struct dlm_ls *ls = lkb->lkb_resource->res_ls;
7fe2b319 DT	216	void (castfn) (void astparam);
7fe2b319 DT	217	void (bastfn) (void astparam, int mode);
8304d6f2 DT	218	struct dlm_callback callbacks[DLM_CALLBACKS_SIZE];
8304d6f2 DT	219	int i, rv, resid;
722d7421	220
23e8e1aa	221	memset(&callbacks, 0, sizeof(callbacks));
e7fd4179	222
23e8e1aa DT	223	mutex_lock(&lkb->lkb_cb_mutex);
	224	if (!lkb->lkb_callbacks[0].seq) {
	225	/* no callback work exists, shouldn't happen */
	226	log_error(ls, "dlm_callback_work %x no work", lkb->lkb_id);
	227	dlm_print_lkb(lkb);
	228	dlm_dump_lkb_callbacks(lkb);
	229	}
e7fd4179	230
23e8e1aa DT	231	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
	232	rv = dlm_rem_lkb_callback(ls, lkb, &callbacks[i], &resid);
	233	if (rv < 0)
	234	break;
	235	}
7fe2b319	236
23e8e1aa DT	237	if (resid) {
	238	/* cbs remain, loop should have removed all, shouldn't happen */
	239	log_error(ls, "dlm_callback_work %x resid %d", lkb->lkb_id,
	240	resid);
	241	dlm_print_lkb(lkb);
	242	dlm_dump_lkb_callbacks(lkb);
	243	}
	244	mutex_unlock(&lkb->lkb_cb_mutex);
7fe2b319	245
23e8e1aa DT	246	castfn = lkb->lkb_astfn;
23e8e1aa DT	247	bastfn = lkb->lkb_bastfn;
7fe2b319	248
23e8e1aa DT	249	for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
	250	if (!callbacks[i].seq)
	251	break;
	252	if (callbacks[i].flags & DLM_CB_SKIP) {
	253	continue;
	254	} else if (callbacks[i].flags & DLM_CB_BAST) {
	255	bastfn(lkb->lkb_astparam, callbacks[i].mode);
	256	} else if (callbacks[i].flags & DLM_CB_CAST) {
	257	lkb->lkb_lksb->sb_status = callbacks[i].sb_status;
	258	lkb->lkb_lksb->sb_flags = callbacks[i].sb_flags;
	259	castfn(lkb->lkb_astparam);
7fe2b319	260	}
e7fd4179	261	}
e7fd4179	262
23e8e1aa DT	263	/* undo kref_get from dlm_add_callback, may cause lkb to be freed */
23e8e1aa DT	264	dlm_put_lkb(lkb);
e7fd4179 DT	265	}
e7fd4179 DT	266
23e8e1aa	267	int dlm_callback_start(struct dlm_ls *ls)
e7fd4179	268	{
23e8e1aa	269	ls->ls_callback_wq = alloc_workqueue("dlm_callback",
10d1459f DT	270	WQ_UNBOUND \|
	271	WQ_MEM_RECLAIM \|
	272	WQ_NON_REENTRANT,
	273	0);
23e8e1aa DT	274	if (!ls->ls_callback_wq) {
	275	log_print("can't start dlm_callback workqueue");
	276	return -ENOMEM;
e7fd4179 DT	277	}
	278	return 0;
	279	}
	280
23e8e1aa	281	void dlm_callback_stop(struct dlm_ls *ls)
e7fd4179	282	{
23e8e1aa DT	283	if (ls->ls_callback_wq)
23e8e1aa DT	284	destroy_workqueue(ls->ls_callback_wq);
e7fd4179 DT	285	}
e7fd4179 DT	286
23e8e1aa	287	void dlm_callback_suspend(struct dlm_ls *ls)
e7fd4179	288	{
23e8e1aa	289	set_bit(LSFL_CB_DELAY, &ls->ls_flags);
e7fd4179	290
23e8e1aa DT	291	if (ls->ls_callback_wq)
23e8e1aa DT	292	flush_workqueue(ls->ls_callback_wq);
e7fd4179 DT	293	}
e7fd4179 DT	294
23e8e1aa	295	void dlm_callback_resume(struct dlm_ls *ls)
e7fd4179	296	{
23e8e1aa DT	297	struct dlm_lkb lkb, safe;
23e8e1aa DT	298	int count = 0;
e7fd4179	299
23e8e1aa DT	300	clear_bit(LSFL_CB_DELAY, &ls->ls_flags);
	301
	302	if (!ls->ls_callback_wq)
	303	return;
	304
	305	mutex_lock(&ls->ls_cb_mutex);
	306	list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
	307	list_del_init(&lkb->lkb_cb_list);
	308	queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
	309	count++;
	310	}
	311	mutex_unlock(&ls->ls_cb_mutex);
	312
	313	log_debug(ls, "dlm_callback_resume %d", count);
e7fd4179 DT	314	}
e7fd4179 DT	315