[linux-2.6-block.git] / fs / cachefiles / main.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* Network filesystem caching backend to use cache files on a premounted
 * filesystem
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/statfs.h>
#include <linux/sysctl.h>
#include <linux/miscdevice.h>
#define CREATE_TRACE_POINTS
#include "internal.h"

unsigned cachefiles_debug;
module_param_named(debug, cachefiles_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(cachefiles_debug, "CacheFiles debugging mask");

MODULE_DESCRIPTION("Mounted-filesystem based cache");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");

struct kmem_cache *cachefiles_object_jar;

static struct miscdevice cachefiles_dev = {
	.minor	= MISC_DYNAMIC_MINOR,
	.name	= "cachefiles",
	.fops	= &cachefiles_daemon_fops,
};

static void cachefiles_object_init_once(void *_object)
{
	struct cachefiles_object *object = _object;

	memset(object, 0, sizeof(*object));
	spin_lock_init(&object->work_lock);
}

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

	ret = misc_register(&cachefiles_dev);
	if (ret < 0)
		goto error_dev;

	/* create an object jar */
	ret = -ENOMEM;
	cachefiles_object_jar =
		kmem_cache_create("cachefiles_object_jar",
				  sizeof(struct cachefiles_object),
				  0,
				  SLAB_HWCACHE_ALIGN,
				  cachefiles_object_init_once);
	if (!cachefiles_object_jar) {
		pr_notice("Failed to allocate an object jar\n");
		goto error_object_jar;
	}

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

	pr_info("Loaded\n");
	return 0;

error_proc:
	kmem_cache_destroy(cachefiles_object_jar);
error_object_jar:
	misc_deregister(&cachefiles_dev);
error_dev:
	pr_err("failed to register: %d\n", ret);
	return ret;
}

fs_initcall(cachefiles_init);

/*
 * clean up on module removal
 */
static void __exit cachefiles_exit(void)
{
	pr_info("Unloading\n");

	cachefiles_proc_cleanup();
	kmem_cache_destroy(cachefiles_object_jar);
	misc_deregister(&cachefiles_dev);
}

module_exit(cachefiles_exit);
Commit	Line	Data
b4d0d230	1	// SPDX-License-Identifier: GPL-2.0-or-later
9ae326a6 DH	2	/* Network filesystem caching backend to use cache files on a premounted
	3	* filesystem
	4	*
	5	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	6	* Written by David Howells (dhowells@redhat.com)
9ae326a6 DH	7	*/
	8
	9	#include <linux/module.h>
	10	#include <linux/init.h>
	11	#include <linux/sched.h>
	12	#include <linux/completion.h>
	13	#include <linux/slab.h>
	14	#include <linux/fs.h>
	15	#include <linux/file.h>
	16	#include <linux/namei.h>
	17	#include <linux/mount.h>
	18	#include <linux/statfs.h>
	19	#include <linux/sysctl.h>
	20	#include <linux/miscdevice.h>
a18feb55	21	#define CREATE_TRACE_POINTS
9ae326a6 DH	22	#include "internal.h"
	23
	24	unsigned cachefiles_debug;
	25	module_param_named(debug, cachefiles_debug, uint, S_IWUSR \| S_IRUGO);
	26	MODULE_PARM_DESC(cachefiles_debug, "CacheFiles debugging mask");
	27
	28	MODULE_DESCRIPTION("Mounted-filesystem based cache");
	29	MODULE_AUTHOR("Red Hat, Inc.");
	30	MODULE_LICENSE("GPL");
	31
	32	struct kmem_cache *cachefiles_object_jar;
	33
	34	static struct miscdevice cachefiles_dev = {
	35	.minor = MISC_DYNAMIC_MINOR,
	36	.name = "cachefiles",
	37	.fops = &cachefiles_daemon_fops,
	38	};
	39
	40	static void cachefiles_object_init_once(void *_object)
	41	{
	42	struct cachefiles_object *object = _object;
	43
	44	memset(object, 0, sizeof(*object));
	45	spin_lock_init(&object->work_lock);
	46	}
	47
	48	/*
	49	* initialise the fs caching module
	50	*/
	51	static int __init cachefiles_init(void)
	52	{
	53	int ret;
	54
	55	ret = misc_register(&cachefiles_dev);
	56	if (ret < 0)
	57	goto error_dev;
	58
	59	/* create an object jar */
	60	ret = -ENOMEM;
	61	cachefiles_object_jar =
	62	kmem_cache_create("cachefiles_object_jar",
	63	sizeof(struct cachefiles_object),
	64	0,
	65	SLAB_HWCACHE_ALIGN,
	66	cachefiles_object_init_once);
	67	if (!cachefiles_object_jar) {
0227d6ab	68	pr_notice("Failed to allocate an object jar\n");
9ae326a6 DH	69	goto error_object_jar;
	70	}
	71
	72	ret = cachefiles_proc_init();
	73	if (ret < 0)
	74	goto error_proc;
	75
0227d6ab	76	pr_info("Loaded\n");
9ae326a6 DH	77	return 0;
	78
	79	error_proc:
	80	kmem_cache_destroy(cachefiles_object_jar);
	81	error_object_jar:
	82	misc_deregister(&cachefiles_dev);
	83	error_dev:
6ff66ac7	84	pr_err("failed to register: %d\n", ret);
9ae326a6 DH	85	return ret;
	86	}
	87
	88	fs_initcall(cachefiles_init);
	89
	90	/*
	91	* clean up on module removal
	92	*/
	93	static void __exit cachefiles_exit(void)
	94	{
0227d6ab	95	pr_info("Unloading\n");
9ae326a6 DH	96
	97	cachefiles_proc_cleanup();
	98	kmem_cache_destroy(cachefiles_object_jar);
	99	misc_deregister(&cachefiles_dev);
	100	}
	101
	102	module_exit(cachefiles_exit);