Wait for outstanding slow work items belonging to a module to clear when unregistering that module as a user of the facility. This prevents the put_ref code of a work item from being taken away before it returns. Signed-off-by: David Howells <dhowells@redhat.com>
		
			
				
	
	
		
			124 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			124 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/* General filesystem local caching manager
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 *
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 * Copyright (C) 2004-2007 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 License
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 * as published by the Free Software Foundation; either version
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 * 2 of the License, or (at your option) any later version.
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 */
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#define FSCACHE_DEBUG_LEVEL CACHE
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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 "internal.h"
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MODULE_DESCRIPTION("FS Cache Manager");
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MODULE_AUTHOR("Red Hat, Inc.");
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MODULE_LICENSE("GPL");
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unsigned fscache_defer_lookup = 1;
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module_param_named(defer_lookup, fscache_defer_lookup, uint,
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		   S_IWUSR | S_IRUGO);
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MODULE_PARM_DESC(fscache_defer_lookup,
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		 "Defer cookie lookup to background thread");
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unsigned fscache_defer_create = 1;
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module_param_named(defer_create, fscache_defer_create, uint,
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		   S_IWUSR | S_IRUGO);
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MODULE_PARM_DESC(fscache_defer_create,
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		 "Defer cookie creation to background thread");
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unsigned fscache_debug;
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module_param_named(debug, fscache_debug, uint,
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		   S_IWUSR | S_IRUGO);
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MODULE_PARM_DESC(fscache_debug,
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		 "FS-Cache debugging mask");
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struct kobject *fscache_root;
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/*
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 * initialise the fs caching module
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 */
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static int __init fscache_init(void)
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{
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	int ret;
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	ret = slow_work_register_user(THIS_MODULE);
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	if (ret < 0)
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		goto error_slow_work;
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	ret = fscache_proc_init();
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	if (ret < 0)
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		goto error_proc;
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	fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
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					       sizeof(struct fscache_cookie),
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					       0,
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					       0,
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					       fscache_cookie_init_once);
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	if (!fscache_cookie_jar) {
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		printk(KERN_NOTICE
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		       "FS-Cache: Failed to allocate a cookie jar\n");
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		ret = -ENOMEM;
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		goto error_cookie_jar;
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	}
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	fscache_root = kobject_create_and_add("fscache", kernel_kobj);
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	if (!fscache_root)
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		goto error_kobj;
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	printk(KERN_NOTICE "FS-Cache: Loaded\n");
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	return 0;
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error_kobj:
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	kmem_cache_destroy(fscache_cookie_jar);
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error_cookie_jar:
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	fscache_proc_cleanup();
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error_proc:
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	slow_work_unregister_user(THIS_MODULE);
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error_slow_work:
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	return ret;
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}
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fs_initcall(fscache_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 fscache_exit(void)
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{
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	_enter("");
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	kobject_put(fscache_root);
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	kmem_cache_destroy(fscache_cookie_jar);
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	fscache_proc_cleanup();
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	slow_work_unregister_user(THIS_MODULE);
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	printk(KERN_NOTICE "FS-Cache: Unloaded\n");
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}
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module_exit(fscache_exit);
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/*
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 * wait_on_bit() sleep function for uninterruptible waiting
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 */
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int fscache_wait_bit(void *flags)
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{
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	schedule();
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	return 0;
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}
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EXPORT_SYMBOL(fscache_wait_bit);
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/*
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 * wait_on_bit() sleep function for interruptible waiting
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 */
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int fscache_wait_bit_interruptible(void *flags)
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{
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	schedule();
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	return signal_pending(current);
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}
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EXPORT_SYMBOL(fscache_wait_bit_interruptible);
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