1// SPDX-License-Identifier: GPL-2.0-or-later
 2/* Network filesystem caching backend to use cache files on a premounted
 3 * filesystem
 4 *
 5 * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
 6 * Written by David Howells (dhowells@redhat.com)
 
 
 
 
 
 7 */
 8
 9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/sched.h>
12#include <linux/completion.h>
13#include <linux/slab.h>
14#include <linux/fs.h>
15#include <linux/file.h>
16#include <linux/namei.h>
17#include <linux/mount.h>
18#include <linux/statfs.h>
19#include <linux/sysctl.h>
20#include <linux/miscdevice.h>
21#include <linux/netfs.h>
22#include <trace/events/netfs.h>
23#define CREATE_TRACE_POINTS
24#include "internal.h"
25
26unsigned cachefiles_debug;
27module_param_named(debug, cachefiles_debug, uint, S_IWUSR | S_IRUGO);
28MODULE_PARM_DESC(cachefiles_debug, "CacheFiles debugging mask");
29
30MODULE_DESCRIPTION("Mounted-filesystem based cache");
31MODULE_AUTHOR("Red Hat, Inc.");
32MODULE_LICENSE("GPL");
33
34struct kmem_cache *cachefiles_object_jar;
35
36static struct miscdevice cachefiles_dev = {
37	.minor	= MISC_DYNAMIC_MINOR,
38	.name	= "cachefiles",
39	.fops	= &cachefiles_daemon_fops,
40};
41
 
 
 
 
 
 
 
 
42/*
43 * initialise the fs caching module
44 */
45static int __init cachefiles_init(void)
46{
47	int ret;
48
49	ret = cachefiles_register_error_injection();
50	if (ret < 0)
51		goto error_einj;
52	ret = misc_register(&cachefiles_dev);
53	if (ret < 0)
54		goto error_dev;
55
56	/* create an object jar */
57	ret = -ENOMEM;
58	cachefiles_object_jar =
59		kmem_cache_create("cachefiles_object_jar",
60				  sizeof(struct cachefiles_object),
61				  0, SLAB_HWCACHE_ALIGN, NULL);
 
 
62	if (!cachefiles_object_jar) {
63		pr_notice("Failed to allocate an object jar\n");
 
64		goto error_object_jar;
65	}
66
67	pr_info("Loaded\n");
 
 
 
 
68	return 0;
69
 
 
70error_object_jar:
71	misc_deregister(&cachefiles_dev);
72error_dev:
73	cachefiles_unregister_error_injection();
74error_einj:
75	pr_err("failed to register: %d\n", ret);
76	return ret;
77}
78
79fs_initcall(cachefiles_init);
80
81/*
82 * clean up on module removal
83 */
84static void __exit cachefiles_exit(void)
85{
86	pr_info("Unloading\n");
87
 
88	kmem_cache_destroy(cachefiles_object_jar);
89	misc_deregister(&cachefiles_dev);
90	cachefiles_unregister_error_injection();
91}
92
93module_exit(cachefiles_exit);

 
  1/* Network filesystem caching backend to use cache files on a premounted
  2 * filesystem
  3 *
  4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  5 * Written by David Howells (dhowells@redhat.com)
  6 *
  7 * This program is free software; you can redistribute it and/or
  8 * modify it under the terms of the GNU General Public Licence
  9 * as published by the Free Software Foundation; either version
 10 * 2 of the Licence, or (at your option) any later version.
 11 */
 12
 13#include <linux/module.h>
 14#include <linux/init.h>
 15#include <linux/sched.h>
 16#include <linux/completion.h>
 17#include <linux/slab.h>
 18#include <linux/fs.h>
 19#include <linux/file.h>
 20#include <linux/namei.h>
 21#include <linux/mount.h>
 22#include <linux/statfs.h>
 23#include <linux/sysctl.h>
 24#include <linux/miscdevice.h>
 
 
 
 25#include "internal.h"
 26
 27unsigned cachefiles_debug;
 28module_param_named(debug, cachefiles_debug, uint, S_IWUSR | S_IRUGO);
 29MODULE_PARM_DESC(cachefiles_debug, "CacheFiles debugging mask");
 30
 31MODULE_DESCRIPTION("Mounted-filesystem based cache");
 32MODULE_AUTHOR("Red Hat, Inc.");
 33MODULE_LICENSE("GPL");
 34
 35struct kmem_cache *cachefiles_object_jar;
 36
 37static struct miscdevice cachefiles_dev = {
 38	.minor	= MISC_DYNAMIC_MINOR,
 39	.name	= "cachefiles",
 40	.fops	= &cachefiles_daemon_fops,
 41};
 42
 43static void cachefiles_object_init_once(void *_object)
 44{
 45	struct cachefiles_object *object = _object;
 46
 47	memset(object, 0, sizeof(*object));
 48	spin_lock_init(&object->work_lock);
 49}
 50
 51/*
 52 * initialise the fs caching module
 53 */
 54static int __init cachefiles_init(void)
 55{
 56	int ret;
 57
 
 
 
 58	ret = misc_register(&cachefiles_dev);
 59	if (ret < 0)
 60		goto error_dev;
 61
 62	/* create an object jar */
 63	ret = -ENOMEM;
 64	cachefiles_object_jar =
 65		kmem_cache_create("cachefiles_object_jar",
 66				  sizeof(struct cachefiles_object),
 67				  0,
 68				  SLAB_HWCACHE_ALIGN,
 69				  cachefiles_object_init_once);
 70	if (!cachefiles_object_jar) {
 71		printk(KERN_NOTICE
 72		       "CacheFiles: Failed to allocate an object jar\n");
 73		goto error_object_jar;
 74	}
 75
 76	ret = cachefiles_proc_init();
 77	if (ret < 0)
 78		goto error_proc;
 79
 80	printk(KERN_INFO "CacheFiles: Loaded\n");
 81	return 0;
 82
 83error_proc:
 84	kmem_cache_destroy(cachefiles_object_jar);
 85error_object_jar:
 86	misc_deregister(&cachefiles_dev);
 87error_dev:
 88	kerror("failed to register: %d", ret);
 
 
 89	return ret;
 90}
 91
 92fs_initcall(cachefiles_init);
 93
 94/*
 95 * clean up on module removal
 96 */
 97static void __exit cachefiles_exit(void)
 98{
 99	printk(KERN_INFO "CacheFiles: Unloading\n");
100
101	cachefiles_proc_cleanup();
102	kmem_cache_destroy(cachefiles_object_jar);
103	misc_deregister(&cachefiles_dev);
 
104}
105
106module_exit(cachefiles_exit);