kernel-ark/fs/gfs2/main.c
Steven Whitehouse 3b8249f617 [GFS2] Fix bz 224480 and cleanup glock demotion code
This patch prevents the printing of a warning message in cases where
the fs is functioning normally by handing off responsibility for
unlinked, but still open inodes, to another node for eventual deallocation.
Also, there is now an improved system for ensuring that such requests
to other nodes do not get lost. The callback on the iopen lock is
only ever called when i_nlink == 0 and when a node is unable to deallocate
it due to it still being in use on another node. When a node receives
the callback therefore, it knows that i_nlink must be zero, so we mark
it as such (in gfs2_drop_inode) in order that it will then attempt
deallocation of the inode itself.

As an additional benefit, queuing a demote request no longer requires
a memory allocation. This simplifies the code for dealing with gfs2_holders
as it removes one special case.

There are two new fields in struct gfs2_glock. gl_demote_state is the
state which the remote node has requested and gl_demote_time is the
time when the request came in. Both fields are only valid when the
GLF_DEMOTE flag is set in gl_flags.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-05-01 09:10:39 +01:00

152 lines
3.5 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.
*/
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/gfs2_ondisk.h>
#include <linux/lm_interface.h>
#include <asm/atomic.h>
#include "gfs2.h"
#include "incore.h"
#include "ops_fstype.h"
#include "sys.h"
#include "util.h"
#include "glock.h"
static void gfs2_init_inode_once(void *foo, struct kmem_cache *cachep, unsigned long flags)
{
struct gfs2_inode *ip = foo;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR) {
inode_init_once(&ip->i_inode);
spin_lock_init(&ip->i_spin);
init_rwsem(&ip->i_rw_mutex);
memset(ip->i_cache, 0, sizeof(ip->i_cache));
}
}
static void gfs2_init_glock_once(void *foo, struct kmem_cache *cachep, unsigned long flags)
{
struct gfs2_glock *gl = foo;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR) {
INIT_HLIST_NODE(&gl->gl_list);
spin_lock_init(&gl->gl_spin);
INIT_LIST_HEAD(&gl->gl_holders);
INIT_LIST_HEAD(&gl->gl_waiters1);
INIT_LIST_HEAD(&gl->gl_waiters3);
gl->gl_lvb = NULL;
atomic_set(&gl->gl_lvb_count, 0);
INIT_LIST_HEAD(&gl->gl_reclaim);
INIT_LIST_HEAD(&gl->gl_ail_list);
atomic_set(&gl->gl_ail_count, 0);
}
}
/**
* init_gfs2_fs - Register GFS2 as a filesystem
*
* Returns: 0 on success, error code on failure
*/
static int __init init_gfs2_fs(void)
{
int error;
error = gfs2_sys_init();
if (error)
return error;
error = gfs2_glock_init();
if (error)
goto fail;
error = -ENOMEM;
gfs2_glock_cachep = kmem_cache_create("gfs2_glock",
sizeof(struct gfs2_glock),
0, 0,
gfs2_init_glock_once, NULL);
if (!gfs2_glock_cachep)
goto fail;
gfs2_inode_cachep = kmem_cache_create("gfs2_inode",
sizeof(struct gfs2_inode),
0, SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD,
gfs2_init_inode_once, NULL);
if (!gfs2_inode_cachep)
goto fail;
gfs2_bufdata_cachep = kmem_cache_create("gfs2_bufdata",
sizeof(struct gfs2_bufdata),
0, 0, NULL, NULL);
if (!gfs2_bufdata_cachep)
goto fail;
error = register_filesystem(&gfs2_fs_type);
if (error)
goto fail;
error = register_filesystem(&gfs2meta_fs_type);
if (error)
goto fail_unregister;
gfs2_register_debugfs();
printk("GFS2 (built %s %s) installed\n", __DATE__, __TIME__);
return 0;
fail_unregister:
unregister_filesystem(&gfs2_fs_type);
fail:
if (gfs2_bufdata_cachep)
kmem_cache_destroy(gfs2_bufdata_cachep);
if (gfs2_inode_cachep)
kmem_cache_destroy(gfs2_inode_cachep);
if (gfs2_glock_cachep)
kmem_cache_destroy(gfs2_glock_cachep);
gfs2_sys_uninit();
return error;
}
/**
* exit_gfs2_fs - Unregister the file system
*
*/
static void __exit exit_gfs2_fs(void)
{
gfs2_unregister_debugfs();
unregister_filesystem(&gfs2_fs_type);
unregister_filesystem(&gfs2meta_fs_type);
kmem_cache_destroy(gfs2_bufdata_cachep);
kmem_cache_destroy(gfs2_inode_cachep);
kmem_cache_destroy(gfs2_glock_cachep);
gfs2_sys_uninit();
}
MODULE_DESCRIPTION("Global File System");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");
module_init(init_gfs2_fs);
module_exit(exit_gfs2_fs);