forked from Minki/linux
3d7a641e54
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>
125 lines
2.9 KiB
C
125 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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