Release 4.10 fs/gfs2/glock.c

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2008 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 version 2.
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/buffer_head.h>
#include <linux/delay.h>
#include <linux/sort.h>
#include <linux/jhash.h>
#include <linux/kallsyms.h>
#include <linux/gfs2_ondisk.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/workqueue.h>
#include <linux/jiffies.h>
#include <linux/rcupdate.h>
#include <linux/rculist_bl.h>
#include <linux/bit_spinlock.h>
#include <linux/percpu.h>
#include <linux/list_sort.h>
#include <linux/lockref.h>
#include <linux/rhashtable.h>

#include "gfs2.h"
#include "incore.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "lops.h"
#include "meta_io.h"
#include "quota.h"
#include "super.h"
#include "util.h"
#include "bmap.h"

#define CREATE_TRACE_POINTS
#include "trace_gfs2.h"


struct gfs2_glock_iter {
	
struct gfs2_sbd *sdp;		/* incore superblock           */
	
struct rhashtable_iter hti;	/* rhashtable iterator         */
	
struct gfs2_glock *gl;		/* current glock struct        */
	
loff_t last_pos;		/* last position               */
};


typedef void (*glock_examiner) (struct gfs2_glock * gl);

static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);


static struct dentry *gfs2_root;

static struct workqueue_struct *glock_workqueue;

struct workqueue_struct *gfs2_delete_workqueue;
static LIST_HEAD(lru_list);

static atomic_t lru_count = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(lru_lock);


#define GFS2_GL_HASH_SHIFT      15

#define GFS2_GL_HASH_SIZE       BIT(GFS2_GL_HASH_SHIFT)


static struct rhashtable_params ht_parms = {
	.nelem_hint = GFS2_GL_HASH_SIZE * 3 / 4,
	.key_len = sizeof(struct lm_lockname),
	.key_offset = offsetof(struct gfs2_glock, gl_name),
	.head_offset = offsetof(struct gfs2_glock, gl_node),
};


static struct rhashtable gl_hash_table;



void gfs2_glock_free(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;

	if (gl->gl_ops->go_flags & GLOF_ASPACE) {
		kmem_cache_free(gfs2_glock_aspace_cachep, gl);
	} else {
		kfree(gl->gl_lksb.sb_lvbptr);
		kmem_cache_free(gfs2_glock_cachep, gl);
	}
	if (atomic_dec_and_test(&sdp->sd_glock_disposal))
		wake_up(&sdp->sd_glock_wait);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
45
58.44%
4
50.00%
david teigland
david teigland
22
28.57%
3
37.50%
robert s. peterson
robert s. peterson
10
12.99%
1
12.50%
Total
77
100.00%
8
100.00%

/**
 * gfs2_glock_hold() - increment reference count on glock
 * @gl: The glock to hold
 *
 */



static void gfs2_glock_hold(struct gfs2_glock *gl)
{
	GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
	lockref_get(&gl->gl_lockref);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
16
50.00%
2
66.67%
david teigland
david teigland
16
50.00%
1
33.33%
Total
32
100.00%
3
100.00%

/**
 * demote_ok - Check to see if it's ok to unlock a glock
 * @gl: the glock
 *
 * Returns: 1 if it's ok
 */



static int demote_ok(const struct gfs2_glock *gl)
{
	const struct gfs2_glock_operations *glops = gl->gl_ops;

	if (gl->gl_state == LM_ST_UNLOCKED)
		return 0;
	if (!list_empty(&gl->gl_holders))
		return 0;
	if (glops->go_demote_ok)
		return glops->go_demote_ok(gl);
	return 1;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
64
100.00%
1
100.00%
Total
64
100.00%
1
100.00%



void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
{
	spin_lock(&lru_lock);

	if (!list_empty(&gl->gl_lru))
		list_del_init(&gl->gl_lru);
	else
		atomic_inc(&lru_count);

	list_add_tail(&gl->gl_lru, &lru_list);
	set_bit(GLF_LRU, &gl->gl_flags);
	spin_unlock(&lru_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
69
100.00%
4
100.00%
Total
69
100.00%
4
100.00%



static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
{
	spin_lock(&lru_lock);
	if (!list_empty(&gl->gl_lru)) {
		list_del_init(&gl->gl_lru);
		atomic_dec(&lru_count);
		clear_bit(GLF_LRU, &gl->gl_flags);
	}
	spin_unlock(&lru_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
53
88.33%
3
75.00%
robert s. peterson
robert s. peterson
7
11.67%
1
25.00%
Total
60
100.00%
4
100.00%

/**
 * gfs2_glock_put() - Decrement reference count on glock
 * @gl: The glock to put
 *
 */



void gfs2_glock_put(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct address_space *mapping = gfs2_glock2aspace(gl);

	if (lockref_put_or_lock(&gl->gl_lockref))
		return;

	lockref_mark_dead(&gl->gl_lockref);

	gfs2_glock_remove_from_lru(gl);
	spin_unlock(&gl->gl_lockref.lock);
	rhashtable_remove_fast(&gl_hash_table, &gl->gl_node, ht_parms);
	GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
	GLOCK_BUG_ON(gl, mapping && mapping->nrpages);
	trace_gfs2_glock_put(gl);
	sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
90
75.63%
10
66.67%
david teigland
david teigland
16
13.45%
1
6.67%
robert s. peterson
robert s. peterson
11
9.24%
3
20.00%
benjamin marzinski
benjamin marzinski
2
1.68%
1
6.67%
Total
119
100.00%
15
100.00%

/**
 * may_grant - check if its ok to grant a new lock
 * @gl: The glock
 * @gh: The lock request which we wish to grant
 *
 * Returns: true if its ok to grant the lock
 */



static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh)
{
	const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list);
	if ((gh->gh_state == LM_ST_EXCLUSIVE ||
	     gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head)
		return 0;
	if (gl->gl_state == gh->gh_state)
		return 1;
	if (gh->gh_flags & GL_EXACT)
		return 0;
	if (gl->gl_state == LM_ST_EXCLUSIVE) {
		if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED)
			return 1;
		if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED)
			return 1;
	}
	if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY))
		return 1;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
127
83.01%
2
66.67%
benjamin marzinski
benjamin marzinski
26
16.99%
1
33.33%
Total
153
100.00%
3
100.00%



static void gfs2_holder_wake(struct gfs2_holder *gh)
{
	clear_bit(HIF_WAIT, &gh->gh_iflags);
	smp_mb__after_atomic();
	wake_up_bit(&gh->gh_iflags, HIF_WAIT);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
33
97.06%
2
66.67%
peter zijlstra
peter zijlstra
1
2.94%
1
33.33%
Total
34
100.00%
3
100.00%

/**
 * do_error - Something unexpected has happened during a lock request
 *
 */



static void do_error(struct gfs2_glock *gl, const int ret)
{
	struct gfs2_holder *gh, *tmp;

	list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
			continue;
		if (ret & LM_OUT_ERROR)
			gh->gh_error = -EIO;
		else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
			gh->gh_error = GLR_TRYFAILED;
		else
			continue;
		list_del_init(&gh->gh_list);
		trace_gfs2_glock_queue(gh, 0);
		gfs2_holder_wake(gh);
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
102
100.00%
1
100.00%
Total
102
100.00%
1
100.00%

/**
 * do_promote - promote as many requests as possible on the current queue
 * @gl: The glock
 * 
 * Returns: 1 if there is a blocked holder at the head of the list, or 2
 *          if a type specific operation is underway.
 */


static int do_promote(struct gfs2_glock *gl)
__releases(&gl->gl_lockref.lock
Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
5
41.67%
1
25.00%
david teigland
david teigland
4
33.33%
1
25.00%
harvey harrison
harvey harrison
2
16.67%
1
25.00%
andreas gruenbacher
andreas gruenbacher
1
8.33%
1
25.00%
Total
12
100.00%
4
100.00%

)
__acquires(&gl->gl_lockref.lock)
{
	const struct gfs2_glock_operations *glops = gl->gl_ops;
	struct gfs2_holder *gh, *tmp;
	int ret;

restart:
	list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
			continue;
		if (may_grant(gl, gh)) {
			if (gh->gh_list.prev == &gl->gl_holders &&
			    glops->go_lock) {
				spin_unlock(&gl->gl_lockref.lock);
				/* FIXME: eliminate this eventually */
				ret = glops->go_lock(gh);
				spin_lock(&gl->gl_lockref.lock);
				if (ret) {
					if (ret == 1)
						return 2;
					gh->gh_error = ret;
					list_del_init(&gh->gh_list);
					trace_gfs2_glock_queue(gh, 0);
					gfs2_holder_wake(gh);
					goto restart;
				}
				set_bit(HIF_HOLDER, &gh->gh_iflags);
				trace_gfs2_promote(gh, 1);
				gfs2_holder_wake(gh);
				goto restart;
			}
			set_bit(HIF_HOLDER, &gh->gh_iflags);
			trace_gfs2_promote(gh, 0);
			gfs2_holder_wake(gh);
			continue;
		}
		if (gh->gh_list.prev == &gl->gl_holders)
			return 1;
		do_error(gl, 0);
		break;
	}
	return 0;
}

/**
 * find_first_waiter - find the first gh that's waiting for the glock
 * @gl: the glock
 */



static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
{
	struct gfs2_holder *gh;

	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
		if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
			return gh;
	}
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
31
63.27%
1
33.33%
david teigland
david teigland
16
32.65%
1
33.33%
pavel emelianov
pavel emelianov
2
4.08%
1
33.33%
Total
49
100.00%
3
100.00%

/**
 * state_change - record that the glock is now in a different state
 * @gl: the glock
 * @new_state the new state
 *
 */



static void state_change(struct gfs2_glock *gl, unsigned int new_state)
{
	int held1, held2;

	held1 = (gl->gl_state != LM_ST_UNLOCKED);
	held2 = (new_state != LM_ST_UNLOCKED);

	if (held1 != held2) {
		GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
		if (held2)
			gl->gl_lockref.count++;
		else
			gl->gl_lockref.count--;
	}
	if (held1 && held2 && list_empty(&gl->gl_holders))
		clear_bit(GLF_QUEUED, &gl->gl_flags);

	if (new_state != gl->gl_target)
		/* shorten our minimum hold time */
		gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
				       GL_GLOCK_MIN_HOLD);
	gl->gl_state = new_state;
	gl->gl_tchange = jiffies;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
112
81.16%
4
66.67%
robert s. peterson
robert s. peterson
24
17.39%
1
16.67%
abhijith das
abhijith das
2
1.45%
1
16.67%
Total
138
100.00%
6
100.00%



static void gfs2_demote_wake(struct gfs2_glock *gl)
{
	gl->gl_demote_state = LM_ST_EXCLUSIVE;
	clear_bit(GLF_DEMOTE, &gl->gl_flags);
	smp_mb__after_atomic();
	wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
abhijith das
abhijith das
33
82.50%
1
33.33%
benjamin marzinski
benjamin marzinski
6
15.00%
1
33.33%
peter zijlstra
peter zijlstra
1
2.50%
1
33.33%
Total
40
100.00%
3
100.00%

/**
 * finish_xmote - The DLM has replied to one of our lock requests
 * @gl: The glock
 * @ret: The status from the DLM
 *
 */



static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
{
	const struct gfs2_glock_operations *glops = gl->gl_ops;
	struct gfs2_holder *gh;
	unsigned state = ret & LM_OUT_ST_MASK;
	int rv;

	spin_lock(&gl->gl_lockref.lock);
	trace_gfs2_glock_state_change(gl, state);
	state_change(gl, state);
	gh = find_first_waiter(gl);

	/* Demote to UN request arrived during demote to SH or DF */
	if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
	    state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
		gl->gl_target = LM_ST_UNLOCKED;

	/* Check for state != intended state */
	if (unlikely(state != gl->gl_target)) {
		if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
			/* move to back of queue and try next entry */
			if (ret & LM_OUT_CANCELED) {
				if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
					list_move_tail(&gh->gh_list, &gl->gl_holders);
				gh = find_first_waiter(gl);
				gl->gl_target = gh->gh_state;
				goto retry;
			}
			/* Some error or failed "try lock" - report it */
			if ((ret & LM_OUT_ERROR) ||
			    (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
				gl->gl_target = gl->gl_state;
				do_error(gl, ret);
				goto out;
			}
		}
		switch(state) {
		/* Unlocked due to conversion deadlock, try again */
		case LM_ST_UNLOCKED:
retry:
			do_xmote(gl, gh, gl->gl_target);
			break;
		/* Conversion fails, unlock and try again */
		case LM_ST_SHARED:
		case LM_ST_DEFERRED:
			do_xmote(gl, gh, LM_ST_UNLOCKED);
			break;
		default: /* Everything else */
			pr_err("wanted %u got %u\n", gl->gl_target, state);
			GLOCK_BUG_ON(gl, 1);
		}
		spin_unlock(&gl->gl_lockref.lock);
		return;
	}

	/* Fast path - we got what we asked for */
	if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
		gfs2_demote_wake(gl);
	if (state != LM_ST_UNLOCKED) {
		if (glops->go_xmote_bh) {
			spin_unlock(&gl->gl_lockref.lock);
			rv = glops->go_xmote_bh(gl, gh);
			spin_lock(&gl->gl_lockref.lock);
			if (rv) {
				do_error(gl, rv);
				goto out;
			}
		}
		rv = do_promote(gl);
		if (rv == 2)
			goto out_locked;
	}
out:
	clear_bit(GLF_LOCK, &gl->gl_flags);
out_locked:
	spin_unlock(&gl->gl_lockref.lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
291
69.78%
5
50.00%
david teigland
david teigland
98
23.50%
1
10.00%
andreas gruenbacher
andreas gruenbacher
15
3.60%
1
10.00%
abhijith das
abhijith das
11
2.64%
1
10.00%
joe perches
joe perches
1
0.24%
1
10.00%
fabian frederick
fabian frederick
1
0.24%
1
10.00%
Total
417
100.00%
10
100.00%

/**
 * do_xmote - Calls the DLM to change the state of a lock
 * @gl: The lock state
 * @gh: The holder (only for promotes)
 * @target: The target lock state
 *
 */


static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
__releases(&gl->gl_lockref.lock
Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
18
85.71%
1
33.33%
harvey harrison
harvey harrison
2
9.52%
1
33.33%
andreas gruenbacher
andreas gruenbacher
1
4.76%
1
33.33%
Total
21
100.00%
3
100.00%

)
__acquires(&gl->gl_lockref.lock)
{
	const struct gfs2_glock_operations *glops = gl->gl_ops;
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	unsigned int lck_flags = (unsigned int)(gh ? gh->gh_flags : 0);
	int ret;

	lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
		      LM_FLAG_PRIORITY);
	GLOCK_BUG_ON(gl, gl->gl_state == target);
	GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
	if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
	    glops->go_inval) {
		set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
		do_error(gl, 0); /* Fail queued try locks */
	}
	gl->gl_req = target;
	set_bit(GLF_BLOCKING, &gl->gl_flags);
	if ((gl->gl_req == LM_ST_UNLOCKED) ||
	    (gl->gl_state == LM_ST_EXCLUSIVE) ||
	    (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
		clear_bit(GLF_BLOCKING, &gl->gl_flags);
	spin_unlock(&gl->gl_lockref.lock);
	if (glops->go_sync)
		glops->go_sync(gl);
	if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
		glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
	clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);

	gfs2_glock_hold(gl);
	if (sdp->sd_lockstruct.ls_ops->lm_lock)	{
		/* lock_dlm */
		ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
		if (ret == -EINVAL && gl->gl_target == LM_ST_UNLOCKED &&
		    target == LM_ST_UNLOCKED &&
		    test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags)) {
			finish_xmote(gl, target);
			if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
				gfs2_glock_put(gl);
		}
		else if (ret) {
			pr_err("lm_lock ret %d\n", ret);
			GLOCK_BUG_ON(gl, 1);
		}
	} else { /* lock_nolock */
		finish_xmote(gl, target);
		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
			gfs2_glock_put(gl);
	}

	spin_lock(&gl->gl_lockref.lock);
}

/**
 * find_first_holder - find the first "holder" gh
 * @gl: the glock
 */



static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
{
	struct gfs2_holder *gh;

	if (!list_empty(&gl->gl_holders)) {
		gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
			return gh;
	}
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
steven whitehouse
steven whitehouse
38
56.72%
2
66.67%
david teigland
david teigland
29
43.28%
1
33.33%
Total
67
100.00%
3
100.00%

/**
 * run_queue - do all outstanding tasks related to a glock
 * @gl: The glock in question
 * @nonblock: True if we must not block in run_queue
 *
 */


static void run_queue(struct gfs2_glock *gl, const int nonblock)
__releases(&gl->gl_lockref.lock
Contributors
Person
Tokens
Prop
Commits
CommitProp
david teigland
david teigland
7
43.75%
1
20.00%
steven whitehouse
steven whitehouse
6
37.50%
2
40.00%
harvey harrison
harvey harrison
2
12.50%
1
20.00%
andreas gruenbacher
andreas gruenbacher
1
6.25%
1
20.00%
Total
16
100.00%
5
100.00%

)
__acquires(&gl->gl_lockref.lock)
{
	struct gfs2_holder *gh = NULL;
	int ret;

	if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
		return;

	GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));

	if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
	    gl->gl_demote_state != gl->gl_state) {
		if (find_first_holder(gl))
			goto out_unlock;
		if (nonblock)
			goto out_sched;
		set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
		GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
		gl->gl_target = gl->gl_demote_state;
	} else {
		if (test_bit(GLF_DEMOTE, &gl->gl_flags))
			gfs2_demote_wake(gl);
		ret = do_promote(gl);
		if (ret == 0)
			goto out_unlock;
		if (ret == 2)
			goto out;
		gh = find_first_waiter(gl);
		gl->gl_target = gh->gh_state;
		if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
			do_error(gl, 0); /* Fail queued try locks */
	}
	do_xmote(gl, gh, gl->gl_target);
out:
	return;

out_sched:
	clear_bit(GLF_LOCK, &gl->gl_flags);
	smp_mb__after_atomic();
	gl->gl_lockref.count++;
	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
		gl->gl_lockref.count--;
	return;

out_unlock:
	clear_bit(GLF_LOCK, &gl->gl_flags);
	smp_mb__after_atomic();
	return;
}



static void delete_work_func(struct work_struct *work)
{
	struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete);
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct inode *inode;
	u64 no_addr = gl->gl_name.ln_number;

	/* If someone's using this glock to create a new dinode, the block must
           have been freed by another node, then re-used, in which case our
           iopen callback is too late after the fact. Ignore it. */
	if (test_bit(GLF_INODE_CREATING, &gl->gl_flags))
		goto out;

	inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED);
	if (inode && !IS_ERR(inode)) {
		d_prune_aliases(inode);
		iput(inode);
	}
out:
	gfs2_glock_put(gl);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
benjamin marzinski
benjamin marzinski
73
66.97%
1
25.00%
robert s. peterson
robert s. peterson
21
19.27%
2
50.00%
steven whitehouse
steven whitehouse
15
13.76%
1
25.00%
Total
109
100.00%
4
100.00%



static void glock_work_func(struct work_struct *work)
{
	unsigned long delay = 0;
	struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
	int drop_ref = 0;

	if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
		finish_xmote(gl, gl->gl_reply);
		drop_ref = 1;
	}
	spin_lock(&gl->gl_lockref.lock);
	if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
	    gl->gl_state != LM_ST_UNLOCKED &&
	    gl->gl_demote_state != LM_ST_EXCLUSIVE) {
		unsigned long holdtime, now = jiffies;

		holdtime = gl->gl_tchange + gl->gl_hold_time;
		if (time_before(now, holdtime))
			delay = holdtime - now;

		if (!delay) {
			clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
			set_bit(GLF_DEMOTE, &gl->gl_flags);
		}
	}
	run_queue(gl, 0);
	spin_unlock(&gl->gl_lockref.lock);
	if (!delay)
		gfs2_glock_put(gl);
	else {
		if (gl->gl_name.ln_type != LM_TYPE_INODE)
			delay = 0;
		if