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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| 
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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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| 
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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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| 
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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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| 
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| struct kmem_cache *cachefiles_object_jar;
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| 
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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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| 
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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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| 
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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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| /*
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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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| 
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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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| 
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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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| 
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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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| 
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| 	pr_info("Loaded\n");
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| 	return 0;
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| 
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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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| 
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| fs_initcall(cachefiles_init);
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| 
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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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| 
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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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| 
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| module_exit(cachefiles_exit);
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