[deliverable/linux.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 int gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
{
	struct gfs2_holder *gh;
	int locked = 0;
	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) {
			locked = 1;
			break;
		}
	}
	spin_unlock(&gl->gl_spin);

	return locked;
}

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);
void gfs2_glock_hold(struct gfs2_glock *gl);
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
	35	static inline int gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
	36	{
	37	struct gfs2_holder *gh;
	38	int locked = 0;
b1e058da	39	struct pid *pid;
b3b94faa DT	40
	41	/* Look in glock's list of holders for one with current task as owner */
	42	spin_lock(&gl->gl_spin);
b1e058da	43	pid = task_pid(current);
b3b94faa	44	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
b1e058da	45	if (gh->gh_owner_pid == pid) {
b3b94faa DT	46	locked = 1;
	47	break;
	48	}
	49	}
	50	spin_unlock(&gl->gl_spin);
	51
	52	return locked;
	53	}
	54
	55	static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
	56	{
50299965	57	return gl->gl_state == LM_ST_EXCLUSIVE;
b3b94faa DT	58	}
	59
	60	static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
	61	{
50299965	62	return gl->gl_state == LM_ST_DEFERRED;
b3b94faa DT	63	}
	64
	65	static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
	66	{
50299965	67	return gl->gl_state == LM_ST_SHARED;
b3b94faa DT	68	}
	69
	70	static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl)
	71	{
	72	int ret;
	73	spin_lock(&gl->gl_spin);
3b8249f6	74	ret = test_bit(GLF_DEMOTE, &gl->gl_flags) \|\| !list_empty(&gl->gl_waiters3);
b3b94faa DT	75	spin_unlock(&gl->gl_spin);
	76	return ret;
	77	}
	78
b3b94faa	79	int gfs2_glock_get(struct gfs2_sbd *sdp,
cd915493	80	u64 number, const struct gfs2_glock_operations *glops,
b3b94faa DT	81	int create, struct gfs2_glock **glp);
	82	void gfs2_glock_hold(struct gfs2_glock *gl);
	83	int gfs2_glock_put(struct gfs2_glock *gl);
190562bd	84	void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
b3b94faa	85	struct gfs2_holder *gh);
190562bd SW	86	void gfs2_holder_reinit(unsigned int state, unsigned flags,
190562bd SW	87	struct gfs2_holder *gh);
b3b94faa	88	void gfs2_holder_uninit(struct gfs2_holder *gh);
b3b94faa DT	89	int gfs2_glock_nq(struct gfs2_holder *gh);
	90	int gfs2_glock_poll(struct gfs2_holder *gh);
	91	int gfs2_glock_wait(struct gfs2_holder *gh);
	92	void gfs2_glock_dq(struct gfs2_holder *gh);
d93cfa98	93	void gfs2_glock_dq_wait(struct gfs2_holder *gh);
b3b94faa	94
b3b94faa DT	95	void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
b3b94faa DT	96	int gfs2_glock_nq_num(struct gfs2_sbd *sdp,
cd915493	97	u64 number, const struct gfs2_glock_operations *glops,
b3b94faa DT	98	unsigned int state, int flags, struct gfs2_holder *gh);
	99
	100	int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	101	void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	102	void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs);
	103
d0dc80db SW	104	/**
	105	* gfs2_glock_nq_init - intialize a holder and enqueue it on a glock
	106	* @gl: the glock
	107	* @state: the state we're requesting
	108	* @flags: the modifier flags
	109	* @gh: the holder structure
	110	*
	111	* Returns: 0, GLR_*, or errno
	112	*/
	113
	114	static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
	115	unsigned int state, int flags,
	116	struct gfs2_holder *gh)
	117	{
	118	int error;
	119
	120	gfs2_holder_init(gl, state, flags, gh);
	121
	122	error = gfs2_glock_nq(gh);
	123	if (error)
	124	gfs2_holder_uninit(gh);
	125
	126	return error;
	127	}
	128
b3b94faa DT	129	/* Lock Value Block functions */
	130
	131	int gfs2_lvb_hold(struct gfs2_glock *gl);
	132	void gfs2_lvb_unhold(struct gfs2_glock *gl);
b3b94faa	133
9b47c11d	134	void gfs2_glock_cb(void cb_data, unsigned int type, void data);
b3b94faa	135
b3b94faa DT	136	void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl);
b3b94faa DT	137	void gfs2_reclaim_glock(struct gfs2_sbd *sdp);
b3b94faa DT	138	void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait);
b3b94faa DT	139
85d1da67	140	int __init gfs2_glock_init(void);
8fbbfd21 SW	141	void gfs2_glock_exit(void);
8fbbfd21 SW	142
7c52b166 RP	143	int gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
	144	void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
	145	int gfs2_register_debugfs(void);
	146	void gfs2_unregister_debugfs(void);
85d1da67	147
b3b94faa	148	#endif /* __GLOCK_DOT_H__ */