[linux-block.git] / fs / fscache / main.c

/* General filesystem local caching manager
 *
 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#define FSCACHE_DEBUG_LEVEL CACHE
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/slab.h>
#include "internal.h"

MODULE_DESCRIPTION("FS Cache Manager");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");

unsigned fscache_defer_lookup = 1;
module_param_named(defer_lookup, fscache_defer_lookup, uint,
		   S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(fscache_defer_lookup,
		 "Defer cookie lookup to background thread");

unsigned fscache_defer_create = 1;
module_param_named(defer_create, fscache_defer_create, uint,
		   S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(fscache_defer_create,
		 "Defer cookie creation to background thread");

unsigned fscache_debug;
module_param_named(debug, fscache_debug, uint,
		   S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(fscache_debug,
		 "FS-Cache debugging mask");

struct kobject *fscache_root;

/*
 * initialise the fs caching module
 */
static int __init fscache_init(void)
{
	int ret;

	ret = slow_work_register_user();
	if (ret < 0)
		goto error_slow_work;

	ret = fscache_proc_init();
	if (ret < 0)
		goto error_proc;

	fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
					       sizeof(struct fscache_cookie),
					       0,
					       0,
					       fscache_cookie_init_once);
	if (!fscache_cookie_jar) {
		printk(KERN_NOTICE
		       "FS-Cache: Failed to allocate a cookie jar\n");
		ret = -ENOMEM;
		goto error_cookie_jar;
	}

	fscache_root = kobject_create_and_add("fscache", kernel_kobj);
	if (!fscache_root)
		goto error_kobj;

	printk(KERN_NOTICE "FS-Cache: Loaded\n");
	return 0;

error_kobj:
	kmem_cache_destroy(fscache_cookie_jar);
error_cookie_jar:
	fscache_proc_cleanup();
error_proc:
	slow_work_unregister_user();
error_slow_work:
	return ret;
}

fs_initcall(fscache_init);

/*
 * clean up on module removal
 */
static void __exit fscache_exit(void)
{
	_enter("");

	kobject_put(fscache_root);
	kmem_cache_destroy(fscache_cookie_jar);
	fscache_proc_cleanup();
	slow_work_unregister_user();
	printk(KERN_NOTICE "FS-Cache: Unloaded\n");
}

module_exit(fscache_exit);

/*
 * wait_on_bit() sleep function for uninterruptible waiting
 */
int fscache_wait_bit(void *flags)
{
	schedule();
	return 0;
}
EXPORT_SYMBOL(fscache_wait_bit);

/*
 * wait_on_bit() sleep function for interruptible waiting
 */
int fscache_wait_bit_interruptible(void *flags)
{
	schedule();
	return signal_pending(current);
}
EXPORT_SYMBOL(fscache_wait_bit_interruptible);
Commit	Line	Data
06b3db1b DH	1	/* General filesystem local caching manager
	2	*
	3	* Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
	12	#define FSCACHE_DEBUG_LEVEL CACHE
	13	#include <linux/module.h>
	14	#include <linux/init.h>
	15	#include <linux/sched.h>
	16	#include <linux/completion.h>
	17	#include <linux/slab.h>
	18	#include "internal.h"
	19
	20	MODULE_DESCRIPTION("FS Cache Manager");
	21	MODULE_AUTHOR("Red Hat, Inc.");
	22	MODULE_LICENSE("GPL");
	23
	24	unsigned fscache_defer_lookup = 1;
	25	module_param_named(defer_lookup, fscache_defer_lookup, uint,
	26	S_IWUSR \| S_IRUGO);
	27	MODULE_PARM_DESC(fscache_defer_lookup,
	28	"Defer cookie lookup to background thread");
	29
	30	unsigned fscache_defer_create = 1;
	31	module_param_named(defer_create, fscache_defer_create, uint,
	32	S_IWUSR \| S_IRUGO);
	33	MODULE_PARM_DESC(fscache_defer_create,
	34	"Defer cookie creation to background thread");
	35
	36	unsigned fscache_debug;
	37	module_param_named(debug, fscache_debug, uint,
	38	S_IWUSR \| S_IRUGO);
	39	MODULE_PARM_DESC(fscache_debug,
	40	"FS-Cache debugging mask");
	41
	42	struct kobject *fscache_root;
	43
	44	/*
	45	* initialise the fs caching module
	46	*/
	47	static int __init fscache_init(void)
	48	{
	49	int ret;
	50
	51	ret = slow_work_register_user();
	52	if (ret < 0)
	53	goto error_slow_work;
	54
7394daa8 DH	55	ret = fscache_proc_init();
	56	if (ret < 0)
	57	goto error_proc;
	58
955d0091 DH	59	fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
	60	sizeof(struct fscache_cookie),
	61	0,
	62	0,
	63	fscache_cookie_init_once);
	64	if (!fscache_cookie_jar) {
	65	printk(KERN_NOTICE
	66	"FS-Cache: Failed to allocate a cookie jar\n");
	67	ret = -ENOMEM;
	68	goto error_cookie_jar;
	69	}
	70
4c515dd4 DH	71	fscache_root = kobject_create_and_add("fscache", kernel_kobj);
	72	if (!fscache_root)
	73	goto error_kobj;
	74
06b3db1b DH	75	printk(KERN_NOTICE "FS-Cache: Loaded\n");
	76	return 0;
	77
4c515dd4	78	error_kobj:
955d0091 DH	79	kmem_cache_destroy(fscache_cookie_jar);
955d0091 DH	80	error_cookie_jar:
4c515dd4	81	fscache_proc_cleanup();
7394daa8 DH	82	error_proc:
7394daa8 DH	83	slow_work_unregister_user();
06b3db1b DH	84	error_slow_work:
	85	return ret;
	86	}
	87
	88	fs_initcall(fscache_init);
	89
	90	/*
	91	* clean up on module removal
	92	*/
	93	static void __exit fscache_exit(void)
	94	{
	95	_enter("");
	96
4c515dd4	97	kobject_put(fscache_root);
955d0091	98	kmem_cache_destroy(fscache_cookie_jar);
7394daa8	99	fscache_proc_cleanup();
06b3db1b DH	100	slow_work_unregister_user();
	101	printk(KERN_NOTICE "FS-Cache: Unloaded\n");
	102	}
	103
	104	module_exit(fscache_exit);
2868cbea DH	105
	106	/*
	107	* wait_on_bit() sleep function for uninterruptible waiting
	108	*/
	109	int fscache_wait_bit(void *flags)
	110	{
	111	schedule();
	112	return 0;
	113	}
	114	EXPORT_SYMBOL(fscache_wait_bit);
	115
	116	/*
	117	* wait_on_bit() sleep function for interruptible waiting
	118	*/
	119	int fscache_wait_bit_interruptible(void *flags)
	120	{
	121	schedule();
	122	return signal_pending(current);
	123	}
	124	EXPORT_SYMBOL(fscache_wait_bit_interruptible);