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// SPDX-License-Identifier: GPL-2.0-or-later
/* Network filesystem caching backend to use cache files on a premounted
* filesystem
*
* Copyright (C) 2021 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>
#include <linux/netfs.h>
#include <trace/events/netfs.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,
};
/*
* initialise the fs caching module
*/
static int __init cachefiles_init(void)
{
int ret;
ret = cachefiles_register_error_injection();
if (ret < 0)
goto error_einj;
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, NULL);
if (!cachefiles_object_jar) {
pr_notice("Failed to allocate an object jar\n");
goto error_object_jar;
}
pr_info("Loaded\n");
return 0;
error_object_jar:
misc_deregister(&cachefiles_dev);
error_dev:
cachefiles_unregister_error_injection();
error_einj:
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");
kmem_cache_destroy(cachefiles_object_jar);
misc_deregister(&cachefiles_dev);
cachefiles_unregister_error_injection();
}
module_exit(cachefiles_exit);
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