1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright �� 2001-2007 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/init.h>
16#include <linux/list.h>
17#include <linux/fs.h>
18#include <linux/err.h>
19#include <linux/mount.h>
20#include <linux/jffs2.h>
21#include <linux/pagemap.h>
22#include <linux/mtd/super.h>
23#include <linux/ctype.h>
24#include <linux/namei.h>
25#include "compr.h"
26#include "nodelist.h"
27
28static void jffs2_put_super(struct super_block *);
29
30static struct kmem_cache *jffs2_inode_cachep;
31
32static struct inode *jffs2_alloc_inode(struct super_block *sb)
33{
34	struct jffs2_inode_info *ei;
35	ei = (struct jffs2_inode_info *)kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
36	if (!ei)
37		return NULL;
38	return &ei->vfs_inode;
39}
40
41static void jffs2_destroy_inode(struct inode *inode)
42{
43	kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
44}
45
46static void jffs2_i_init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
47{
48	struct jffs2_inode_info *ei = (struct jffs2_inode_info *) foo;
49
50	init_MUTEX(&ei->sem);
51	inode_init_once(&ei->vfs_inode);
52}
53
54static int jffs2_sync_fs(struct super_block *sb, int wait)
55{
56	struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
57
58	down(&c->alloc_sem);
59	jffs2_flush_wbuf_pad(c);
60	up(&c->alloc_sem);
61	return 0;
62}
63
64static const struct super_operations jffs2_super_operations =
65{
66	.alloc_inode =	jffs2_alloc_inode,
67	.destroy_inode =jffs2_destroy_inode,
68	.read_inode =	jffs2_read_inode,
69	.put_super =	jffs2_put_super,
70	.write_super =	jffs2_write_super,
71	.statfs =	jffs2_statfs,
72	.remount_fs =	jffs2_remount_fs,
73	.clear_inode =	jffs2_clear_inode,
74	.dirty_inode =	jffs2_dirty_inode,
75	.sync_fs =	jffs2_sync_fs,
76};
77
78/*
79 * fill in the superblock
80 */
81static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
82{
83	struct jffs2_sb_info *c;
84
85	D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
86		  " New superblock for device %d (\"%s\")\n",
87		  sb->s_mtd->index, sb->s_mtd->name));
88
89	c = kzalloc(sizeof(*c), GFP_KERNEL);
90	if (!c)
91		return -ENOMEM;
92
93	c->mtd = sb->s_mtd;
94	c->os_priv = sb;
95	sb->s_fs_info = c;
96
97	/* Initialize JFFS2 superblock locks, the further initialization will
98	 * be done later */
99	init_MUTEX(&c->alloc_sem);
100	init_MUTEX(&c->erase_free_sem);
101	init_waitqueue_head(&c->erase_wait);
102	init_waitqueue_head(&c->inocache_wq);
103	spin_lock_init(&c->erase_completion_lock);
104	spin_lock_init(&c->inocache_lock);
105
106	sb->s_op = &jffs2_super_operations;
107	sb->s_flags = sb->s_flags | MS_NOATIME;
108	sb->s_xattr = jffs2_xattr_handlers;
109#ifdef CONFIG_JFFS2_FS_POSIX_ACL
110	sb->s_flags |= MS_POSIXACL;
111#endif
112	return jffs2_do_fill_super(sb, data, silent);
113}
114
115static int jffs2_get_sb(struct file_system_type *fs_type,
116			int flags, const char *dev_name,
117			void *data, struct vfsmount *mnt)
118{
119	return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
120			  mnt);
121}
122
123static void jffs2_put_super (struct super_block *sb)
124{
125	struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
126
127	D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
128
129	down(&c->alloc_sem);
130	jffs2_flush_wbuf_pad(c);
131	up(&c->alloc_sem);
132
133	jffs2_sum_exit(c);
134
135	jffs2_free_ino_caches(c);
136	jffs2_free_raw_node_refs(c);
137	if (jffs2_blocks_use_vmalloc(c))
138		vfree(c->blocks);
139	else
140		kfree(c->blocks);
141	jffs2_flash_cleanup(c);
142	kfree(c->inocache_list);
143	jffs2_clear_xattr_subsystem(c);
144	if (c->mtd->sync)
145		c->mtd->sync(c->mtd);
146
147	D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
148}
149
150static void jffs2_kill_sb(struct super_block *sb)
151{
152	struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
153	if (!(sb->s_flags & MS_RDONLY))
154		jffs2_stop_garbage_collect_thread(c);
155	kill_mtd_super(sb);
156	kfree(c);
157}
158
159static struct file_system_type jffs2_fs_type = {
160	.owner =	THIS_MODULE,
161	.name =		"jffs2",
162	.get_sb =	jffs2_get_sb,
163	.kill_sb =	jffs2_kill_sb,
164};
165
166static int __init init_jffs2_fs(void)
167{
168	int ret;
169
170	/* Paranoia checks for on-medium structures. If we ask GCC
171	   to pack them with __attribute__((packed)) then it _also_
172	   assumes that they're not aligned -- so it emits crappy
173	   code on some architectures. Ideally we want an attribute
174	   which means just 'no padding', without the alignment
175	   thing. But GCC doesn't have that -- we have to just
176	   hope the structs are the right sizes, instead. */
177	BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
178	BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
179	BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
180	BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
181
182	printk(KERN_INFO "JFFS2 version 2.2."
183#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
184	       " (NAND)"
185#endif
186#ifdef CONFIG_JFFS2_SUMMARY
187	       " (SUMMARY) "
188#endif
189	       " �� 2001-2006 Red Hat, Inc.\n");
190
191	jffs2_inode_cachep = kmem_cache_create("jffs2_i",
192					     sizeof(struct jffs2_inode_info),
193					     0, (SLAB_RECLAIM_ACCOUNT|
194						SLAB_MEM_SPREAD),
195					     jffs2_i_init_once, NULL);
196	if (!jffs2_inode_cachep) {
197		printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
198		return -ENOMEM;
199	}
200	ret = jffs2_compressors_init();
201	if (ret) {
202		printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
203		goto out;
204	}
205	ret = jffs2_create_slab_caches();
206	if (ret) {
207		printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
208		goto out_compressors;
209	}
210	ret = register_filesystem(&jffs2_fs_type);
211	if (ret) {
212		printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
213		goto out_slab;
214	}
215	return 0;
216
217 out_slab:
218	jffs2_destroy_slab_caches();
219 out_compressors:
220	jffs2_compressors_exit();
221 out:
222	kmem_cache_destroy(jffs2_inode_cachep);
223	return ret;
224}
225
226static void __exit exit_jffs2_fs(void)
227{
228	unregister_filesystem(&jffs2_fs_type);
229	jffs2_destroy_slab_caches();
230	jffs2_compressors_exit();
231	kmem_cache_destroy(jffs2_inode_cachep);
232}
233
234module_init(init_jffs2_fs);
235module_exit(exit_jffs2_fs);
236
237MODULE_DESCRIPTION("The Journalling Flash File System, v2");
238MODULE_AUTHOR("Red Hat, Inc.");
239MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
240		       // the sake of this tag. It's Free Software.
241