mirror of https://gitee.com/openkylin/linux.git
107 lines
2.4 KiB
C
107 lines
2.4 KiB
C
/* Network filesystem caching backend to use cache files on a premounted
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* filesystem
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*
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* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/completion.h>
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#include <linux/slab.h>
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#include <linux/fs.h>
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#include <linux/file.h>
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#include <linux/namei.h>
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#include <linux/mount.h>
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#include <linux/statfs.h>
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#include <linux/sysctl.h>
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#include <linux/miscdevice.h>
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#define CREATE_TRACE_POINTS
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#include "internal.h"
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unsigned cachefiles_debug;
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module_param_named(debug, cachefiles_debug, uint, S_IWUSR | S_IRUGO);
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MODULE_PARM_DESC(cachefiles_debug, "CacheFiles debugging mask");
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MODULE_DESCRIPTION("Mounted-filesystem based cache");
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MODULE_AUTHOR("Red Hat, Inc.");
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MODULE_LICENSE("GPL");
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struct kmem_cache *cachefiles_object_jar;
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static struct miscdevice cachefiles_dev = {
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.minor = MISC_DYNAMIC_MINOR,
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.name = "cachefiles",
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.fops = &cachefiles_daemon_fops,
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};
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static void cachefiles_object_init_once(void *_object)
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{
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struct cachefiles_object *object = _object;
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memset(object, 0, sizeof(*object));
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spin_lock_init(&object->work_lock);
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}
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/*
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* initialise the fs caching module
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*/
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static int __init cachefiles_init(void)
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{
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int ret;
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ret = misc_register(&cachefiles_dev);
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if (ret < 0)
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goto error_dev;
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/* create an object jar */
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ret = -ENOMEM;
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cachefiles_object_jar =
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kmem_cache_create("cachefiles_object_jar",
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sizeof(struct cachefiles_object),
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0,
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SLAB_HWCACHE_ALIGN,
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cachefiles_object_init_once);
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if (!cachefiles_object_jar) {
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pr_notice("Failed to allocate an object jar\n");
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goto error_object_jar;
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}
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ret = cachefiles_proc_init();
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if (ret < 0)
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goto error_proc;
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pr_info("Loaded\n");
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return 0;
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error_proc:
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kmem_cache_destroy(cachefiles_object_jar);
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error_object_jar:
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misc_deregister(&cachefiles_dev);
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error_dev:
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pr_err("failed to register: %d\n", ret);
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return ret;
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}
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fs_initcall(cachefiles_init);
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/*
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* clean up on module removal
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*/
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static void __exit cachefiles_exit(void)
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{
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pr_info("Unloading\n");
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cachefiles_proc_cleanup();
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kmem_cache_destroy(cachefiles_object_jar);
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misc_deregister(&cachefiles_dev);
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}
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module_exit(cachefiles_exit);
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