[net-next-2.6.git] / fs / gfs2 / glock.h

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2006 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.
 */

#ifndef __GLOCK_DOT_H__
#define __GLOCK_DOT_H__

#include <linux/sched.h>
#include "incore.h"

/* Flags for lock requests; used in gfs2_holder gh_flag field.
   From lm_interface.h:
#define LM_FLAG_TRY		0x00000001
#define LM_FLAG_TRY_1CB		0x00000002
#define LM_FLAG_NOEXP		0x00000004
#define LM_FLAG_ANY		0x00000008
#define LM_FLAG_PRIORITY	0x00000010 */

#define GL_ASYNC		0x00000040
#define GL_EXACT		0x00000080
#define GL_SKIP			0x00000100
#define GL_ATIME		0x00000200
#define GL_NOCACHE		0x00000400
#define GL_FLOCK		0x00000800
#define GL_NOCANCEL		0x00001000

#define GLR_TRYFAILED		13
#define GLR_CANCELED		14

static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
{
	struct gfs2_holder *gh;
	struct pid *pid;

	/* Look in glock's list of holders for one with current task as owner */
	spin_lock(&gl->gl_spin);
	pid = task_pid(current);
	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
		if (gh->gh_owner_pid == pid)
			goto out;
	}
	gh = NULL;
out:
	spin_unlock(&gl->gl_spin);

	return gh;
}

static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
{
	return gl->gl_state == LM_ST_EXCLUSIVE;
}

static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
{
	return gl->gl_state == LM_ST_DEFERRED;
}

static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
{
	return gl->gl_state == LM_ST_SHARED;
}

static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl)
{
	int ret;
	spin_lock(&gl->gl_spin);
	ret = test_bit(GLF_DEMOTE, &gl->gl_flags) || !list_empty(&gl->gl_waiters3);
	spin_unlock(&gl->gl_spin);
	return ret;
}

int gfs2_glock_get(struct gfs2_sbd *sdp,
		   u64 number, const struct gfs2_glock_operations *glops,
		   int create, struct gfs2_glock **glp);
int gfs2_glock_put(struct gfs2_glock *gl);
void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
		      struct gfs2_holder *gh);
void gfs2_holder_reinit(unsigned int state, unsigned flags,
			struct gfs2_holder *gh);
void gfs2_holder_uninit(struct gfs2_holder *gh);
int gfs2_glock_nq(struct gfs2_holder *gh);
int gfs2_glock_poll(struct gfs2_holder *gh);
int gfs2_glock_wait(struct gfs2_holder *gh);
void gfs2_glock_dq(struct gfs2_holder *gh);
void gfs2_glock_dq_wait(struct gfs2_holder *gh);

void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
int gfs2_glock_nq_num(struct gfs2_sbd *sdp,
		      u64 number, const struct gfs2_glock_operations *glops,
		      unsigned int state, int flags, struct gfs2_holder *gh);

int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs);

/**
 * gfs2_glock_nq_init - intialize a holder and enqueue it on a glock
 * @gl: the glock
 * @state: the state we're requesting
 * @flags: the modifier flags
 * @gh: the holder structure
 *
 * Returns: 0, GLR_*, or errno
 */

static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
				     unsigned int state, int flags,
				     struct gfs2_holder *gh)
{
	int error;

	gfs2_holder_init(gl, state, flags, gh);

	error = gfs2_glock_nq(gh);
	if (error)
		gfs2_holder_uninit(gh);

	return error;
}

/*  Lock Value Block functions  */

int gfs2_lvb_hold(struct gfs2_glock *gl);
void gfs2_lvb_unhold(struct gfs2_glock *gl);

void gfs2_glock_cb(void *cb_data, unsigned int type, void *data);

void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl);
void gfs2_reclaim_glock(struct gfs2_sbd *sdp);
void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait);

int __init gfs2_glock_init(void);
void gfs2_glock_exit(void);

int gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
int gfs2_register_debugfs(void);
void gfs2_unregister_debugfs(void);

#endif /* __GLOCK_DOT_H__ */
Commit	Line	Data
b3b94faa DT	1	/*
b3b94faa DT	2	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3a8a9a10	3	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
b3b94faa DT	4	*
	5	* This copyrighted material is made available to anyone wishing to use,
	6	* modify, copy, or redistribute it subject to the terms and conditions
e9fc2aa0	7	* of the GNU General Public License version 2.
b3b94faa DT	8	*/
	9
	10	#ifndef __GLOCK_DOT_H__
	11	#define __GLOCK_DOT_H__
	12
e8edc6e0	13	#include <linux/sched.h>
f2f7ba52 SW	14	#include "incore.h"
f2f7ba52 SW	15
b3b94faa DT	16	/* Flags for lock requests; used in gfs2_holder gh_flag field.
	17	From lm_interface.h:
	18	#define LM_FLAG_TRY 0x00000001
	19	#define LM_FLAG_TRY_1CB 0x00000002
	20	#define LM_FLAG_NOEXP 0x00000004
	21	#define LM_FLAG_ANY 0x00000008
	22	#define LM_FLAG_PRIORITY 0x00000010 */
	23
b3b94faa DT	24	#define GL_ASYNC 0x00000040
	25	#define GL_EXACT 0x00000080
	26	#define GL_SKIP 0x00000100
	27	#define GL_ATIME 0x00000200
	28	#define GL_NOCACHE 0x00000400
b4c20166	29	#define GL_FLOCK 0x00000800
b3b94faa	30	#define GL_NOCANCEL 0x00001000
b3b94faa DT	31
	32	#define GLR_TRYFAILED 13
	33	#define GLR_CANCELED 14
	34
7afd88d9	35	static inline struct gfs2_holder gfs2_glock_is_locked_by_me(struct gfs2_glock gl)
b3b94faa DT	36	{
b3b94faa DT	37	struct gfs2_holder *gh;
b1e058da	38	struct pid *pid;
b3b94faa DT	39
	40	/* Look in glock's list of holders for one with current task as owner */
	41	spin_lock(&gl->gl_spin);
b1e058da	42	pid = task_pid(current);
b3b94faa	43	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
7afd88d9 SW	44	if (gh->gh_owner_pid == pid)
7afd88d9 SW	45	goto out;
b3b94faa	46	}
7afd88d9 SW	47	gh = NULL;
7afd88d9 SW	48	out:
b3b94faa DT	49	spin_unlock(&gl->gl_spin);
b3b94faa DT	50
7afd88d9	51	return gh;
b3b94faa DT	52	}
	53
	54	static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
	55	{
50299965	56	return gl->gl_state == LM_ST_EXCLUSIVE;
b3b94faa DT	57	}
	58
	59	static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
	60	{
50299965	61	return gl->gl_state == LM_ST_DEFERRED;
b3b94faa DT	62	}
	63
	64	static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
	65	{
50299965	66	return gl->gl_state == LM_ST_SHARED;
b3b94faa DT	67	}
	68
	69	static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl)
	70	{
	71	int ret;
	72	spin_lock(&gl->gl_spin);
3b8249f6	73	ret = test_bit(GLF_DEMOTE, &gl->gl_flags) \|\| !list_empty(&gl->gl_waiters3);
b3b94faa DT	74	spin_unlock(&gl->gl_spin);
	75	return ret;
	76	}
	77
b3b94faa	78	int gfs2_glock_get(struct gfs2_sbd *sdp,
cd915493	79	u64 number, const struct gfs2_glock_operations *glops,
b3b94faa	80	int create, struct gfs2_glock **glp);
b3b94faa	81	int gfs2_glock_put(struct gfs2_glock *gl);
190562bd	82	void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
b3b94faa	83	struct gfs2_holder *gh);
190562bd SW	84	void gfs2_holder_reinit(unsigned int state, unsigned flags,
190562bd SW	85	struct gfs2_holder *gh);
b3b94faa	86	void gfs2_holder_uninit(struct gfs2_holder *gh);
b3b94faa DT	87	int gfs2_glock_nq(struct gfs2_holder *gh);
	88	int gfs2_glock_poll(struct gfs2_holder *gh);
	89	int gfs2_glock_wait(struct gfs2_holder *gh);
	90	void gfs2_glock_dq(struct gfs2_holder *gh);
d93cfa98	91	void gfs2_glock_dq_wait(struct gfs2_holder *gh);
b3b94faa	92
b3b94faa DT	93	void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
b3b94faa DT	94	int gfs2_glock_nq_num(struct gfs2_sbd *sdp,
cd915493	95	u64 number, const struct gfs2_glock_operations *glops,
b3b94faa DT	96	unsigned int state, int flags, struct gfs2_holder *gh);
	97
	98	int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	99	void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	100	void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs);
	101
d0dc80db SW	102	/**
	103	* gfs2_glock_nq_init - intialize a holder and enqueue it on a glock
	104	* @gl: the glock
	105	* @state: the state we're requesting
	106	* @flags: the modifier flags
	107	* @gh: the holder structure
	108	*
	109	* Returns: 0, GLR_*, or errno
	110	*/
	111
	112	static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
	113	unsigned int state, int flags,
	114	struct gfs2_holder *gh)
	115	{
	116	int error;
	117
	118	gfs2_holder_init(gl, state, flags, gh);
	119
	120	error = gfs2_glock_nq(gh);
	121	if (error)
	122	gfs2_holder_uninit(gh);
	123
	124	return error;
	125	}
	126
b3b94faa DT	127	/* Lock Value Block functions */
	128
	129	int gfs2_lvb_hold(struct gfs2_glock *gl);
	130	void gfs2_lvb_unhold(struct gfs2_glock *gl);
b3b94faa	131
9b47c11d	132	void gfs2_glock_cb(void cb_data, unsigned int type, void data);
b3b94faa	133
b3b94faa DT	134	void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl);
b3b94faa DT	135	void gfs2_reclaim_glock(struct gfs2_sbd *sdp);
b3b94faa DT	136	void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait);
b3b94faa DT	137
85d1da67	138	int __init gfs2_glock_init(void);
8fbbfd21 SW	139	void gfs2_glock_exit(void);
8fbbfd21 SW	140
7c52b166 RP	141	int gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
	142	void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
	143	int gfs2_register_debugfs(void);
	144	void gfs2_unregister_debugfs(void);
85d1da67	145
b3b94faa	146	#endif /* __GLOCK_DOT_H__ */