linux/fs/gfs2/glock.h
Steven Whitehouse 85d1da67f7 [GFS2] Move glock hash table out of superblock
There are several reasons why we want to do this:
 - Firstly its large and thus we'll scale better with multiple
   GFS2 fs mounted at the same time
 - Secondly its easier to scale its size as required (thats a plan
   for later patches)
 - Thirdly, we can use kzalloc rather than vmalloc when allocating
   the superblock (its now only 4888 bytes)
 - Fourth its all part of my plan to eventually be able to use RCU
   with the glock hash.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-07 14:40:21 -04:00

156 lines
4.4 KiB
C

/*
* 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 "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_LOCAL_EXCL 0x00000020
#define GL_ASYNC 0x00000040
#define GL_EXACT 0x00000080
#define GL_SKIP 0x00000100
#define GL_ATIME 0x00000200
#define GL_NOCACHE 0x00000400
#define GL_NOCANCEL 0x00001000
#define GL_AOP 0x00004000
#define GL_DUMP 0x00008000
#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;
/* Look in glock's list of holders for one with current task as owner */
spin_lock(&gl->gl_spin);
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
if (gh->gh_owner == current) {
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 = !list_empty(&gl->gl_waiters2) || !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);
void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags);
void gfs2_glock_drop_th(struct gfs2_glock *gl);
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);
int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time);
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);
void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, u64 number,
const struct gfs2_glock_operations *glops,
unsigned int state, int flags);
void gfs2_glock_inode_squish(struct inode *inode);
/**
* 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(lm_fsdata_t *fsdata, unsigned int type, void *data);
void gfs2_iopen_go_callback(struct gfs2_glock *gl, unsigned int state);
void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl);
void gfs2_reclaim_glock(struct gfs2_sbd *sdp);
void gfs2_scand_internal(struct gfs2_sbd *sdp);
void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait);
int __init gfs2_glock_init(void);
#endif /* __GLOCK_DOT_H__ */