2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright © 2001-2007 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@infradead.org>
8 * For licensing information, see the file 'LICENCE' in this directory.
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>
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 <linux/exportfs.h>
29 static void jffs2_put_super(struct super_block *);
31 static struct kmem_cache *jffs2_inode_cachep;
33 static struct inode *jffs2_alloc_inode(struct super_block *sb)
35 struct jffs2_inode_info *f;
37 f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
43 static void jffs2_destroy_inode(struct inode *inode)
45 kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
48 static void jffs2_i_init_once(void *foo)
50 struct jffs2_inode_info *f = foo;
53 inode_init_once(&f->vfs_inode);
56 static int jffs2_sync_fs(struct super_block *sb, int wait)
58 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
60 mutex_lock(&c->alloc_sem);
61 jffs2_flush_wbuf_pad(c);
62 mutex_unlock(&c->alloc_sem);
66 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
69 /* We don't care about i_generation. We'll destroy the flash
70 before we start re-using inode numbers anyway. And even
71 if that wasn't true, we'd have other problems...*/
72 return jffs2_iget(sb, ino);
75 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
76 int fh_len, int fh_type)
78 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
82 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
83 int fh_len, int fh_type)
85 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
89 static struct dentry *jffs2_get_parent(struct dentry *child)
91 struct jffs2_inode_info *f;
94 BUG_ON(!S_ISDIR(child->d_inode->i_mode));
96 f = JFFS2_INODE_INFO(child->d_inode);
98 pino = f->inocache->pino_nlink;
100 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
101 f->inocache->ino, pino);
103 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
106 static struct export_operations jffs2_export_ops = {
107 .get_parent = jffs2_get_parent,
108 .fh_to_dentry = jffs2_fh_to_dentry,
109 .fh_to_parent = jffs2_fh_to_parent,
112 static const struct super_operations jffs2_super_operations =
114 .alloc_inode = jffs2_alloc_inode,
115 .destroy_inode =jffs2_destroy_inode,
116 .put_super = jffs2_put_super,
117 .write_super = jffs2_write_super,
118 .statfs = jffs2_statfs,
119 .remount_fs = jffs2_remount_fs,
120 .clear_inode = jffs2_clear_inode,
121 .dirty_inode = jffs2_dirty_inode,
122 .sync_fs = jffs2_sync_fs,
126 * fill in the superblock
128 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
130 struct jffs2_sb_info *c;
132 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
133 " New superblock for device %d (\"%s\")\n",
134 sb->s_mtd->index, sb->s_mtd->name));
136 c = kzalloc(sizeof(*c), GFP_KERNEL);
144 /* Initialize JFFS2 superblock locks, the further initialization will
146 mutex_init(&c->alloc_sem);
147 mutex_init(&c->erase_free_sem);
148 init_waitqueue_head(&c->erase_wait);
149 init_waitqueue_head(&c->inocache_wq);
150 spin_lock_init(&c->erase_completion_lock);
151 spin_lock_init(&c->inocache_lock);
153 sb->s_op = &jffs2_super_operations;
154 sb->s_export_op = &jffs2_export_ops;
155 sb->s_flags = sb->s_flags | MS_NOATIME;
156 sb->s_xattr = jffs2_xattr_handlers;
157 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
158 sb->s_flags |= MS_POSIXACL;
160 return jffs2_do_fill_super(sb, data, silent);
163 static int jffs2_get_sb(struct file_system_type *fs_type,
164 int flags, const char *dev_name,
165 void *data, struct vfsmount *mnt)
167 return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
171 static void jffs2_put_super (struct super_block *sb)
173 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
175 D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
180 jffs2_write_super(sb);
182 mutex_lock(&c->alloc_sem);
183 jffs2_flush_wbuf_pad(c);
184 mutex_unlock(&c->alloc_sem);
188 jffs2_free_ino_caches(c);
189 jffs2_free_raw_node_refs(c);
190 if (jffs2_blocks_use_vmalloc(c))
194 jffs2_flash_cleanup(c);
195 kfree(c->inocache_list);
196 jffs2_clear_xattr_subsystem(c);
198 c->mtd->sync(c->mtd);
202 D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
205 static void jffs2_kill_sb(struct super_block *sb)
207 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
208 if (!(sb->s_flags & MS_RDONLY))
209 jffs2_stop_garbage_collect_thread(c);
214 static struct file_system_type jffs2_fs_type = {
215 .owner = THIS_MODULE,
217 .get_sb = jffs2_get_sb,
218 .kill_sb = jffs2_kill_sb,
221 static int __init init_jffs2_fs(void)
225 /* Paranoia checks for on-medium structures. If we ask GCC
226 to pack them with __attribute__((packed)) then it _also_
227 assumes that they're not aligned -- so it emits crappy
228 code on some architectures. Ideally we want an attribute
229 which means just 'no padding', without the alignment
230 thing. But GCC doesn't have that -- we have to just
231 hope the structs are the right sizes, instead. */
232 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
233 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
234 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
235 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
237 printk(KERN_INFO "JFFS2 version 2.2."
238 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
241 #ifdef CONFIG_JFFS2_SUMMARY
244 " © 2001-2006 Red Hat, Inc.\n");
246 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
247 sizeof(struct jffs2_inode_info),
248 0, (SLAB_RECLAIM_ACCOUNT|
251 if (!jffs2_inode_cachep) {
252 printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
255 ret = jffs2_compressors_init();
257 printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
260 ret = jffs2_create_slab_caches();
262 printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
263 goto out_compressors;
265 ret = register_filesystem(&jffs2_fs_type);
267 printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
273 jffs2_destroy_slab_caches();
275 jffs2_compressors_exit();
277 kmem_cache_destroy(jffs2_inode_cachep);
281 static void __exit exit_jffs2_fs(void)
283 unregister_filesystem(&jffs2_fs_type);
284 jffs2_destroy_slab_caches();
285 jffs2_compressors_exit();
286 kmem_cache_destroy(jffs2_inode_cachep);
289 module_init(init_jffs2_fs);
290 module_exit(exit_jffs2_fs);
292 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
293 MODULE_AUTHOR("Red Hat, Inc.");
294 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
295 // the sake of this tag. It's Free Software.