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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/list.h>
20 #include <linux/err.h>
21 #include <linux/mount.h>
22 #include <linux/parser.h>
23 #include <linux/jffs2.h>
24 #include <linux/pagemap.h>
25 #include <linux/mtd/super.h>
26 #include <linux/ctype.h>
27 #include <linux/namei.h>
28 #include <linux/seq_file.h>
29 #include <linux/exportfs.h>
33 static void jffs2_put_super(struct super_block *);
35 static struct kmem_cache *jffs2_inode_cachep;
37 static struct inode *jffs2_alloc_inode(struct super_block *sb)
39 struct jffs2_inode_info *f;
41 f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
47 static void jffs2_i_callback(struct rcu_head *head)
49 struct inode *inode = container_of(head, struct inode, i_rcu);
50 kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
53 static void jffs2_destroy_inode(struct inode *inode)
55 call_rcu(&inode->i_rcu, jffs2_i_callback);
58 static void jffs2_i_init_once(void *foo)
60 struct jffs2_inode_info *f = foo;
63 inode_init_once(&f->vfs_inode);
66 static const char *jffs2_compr_name(unsigned int compr)
69 case JFFS2_COMPR_MODE_NONE:
71 #ifdef CONFIG_JFFS2_LZO
72 case JFFS2_COMPR_MODE_FORCELZO:
75 #ifdef CONFIG_JFFS2_ZLIB
76 case JFFS2_COMPR_MODE_FORCEZLIB:
80 /* should never happen; programmer error */
86 static int jffs2_show_options(struct seq_file *s, struct dentry *root)
88 struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb);
89 struct jffs2_mount_opts *opts = &c->mount_opts;
91 if (opts->override_compr)
92 seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
97 static int jffs2_sync_fs(struct super_block *sb, int wait)
99 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
101 mutex_lock(&c->alloc_sem);
102 jffs2_flush_wbuf_pad(c);
103 mutex_unlock(&c->alloc_sem);
107 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
110 /* We don't care about i_generation. We'll destroy the flash
111 before we start re-using inode numbers anyway. And even
112 if that wasn't true, we'd have other problems...*/
113 return jffs2_iget(sb, ino);
116 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
117 int fh_len, int fh_type)
119 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
120 jffs2_nfs_get_inode);
123 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
124 int fh_len, int fh_type)
126 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
127 jffs2_nfs_get_inode);
130 static struct dentry *jffs2_get_parent(struct dentry *child)
132 struct jffs2_inode_info *f;
135 BUG_ON(!S_ISDIR(child->d_inode->i_mode));
137 f = JFFS2_INODE_INFO(child->d_inode);
139 pino = f->inocache->pino_nlink;
141 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
142 f->inocache->ino, pino);
144 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
147 static const struct export_operations jffs2_export_ops = {
148 .get_parent = jffs2_get_parent,
149 .fh_to_dentry = jffs2_fh_to_dentry,
150 .fh_to_parent = jffs2_fh_to_parent,
154 * JFFS2 mount options.
156 * Opt_override_compr: override default compressor
157 * Opt_err: just end of array marker
164 static const match_table_t tokens = {
165 {Opt_override_compr, "compr=%s"},
169 static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
171 substring_t args[MAX_OPT_ARGS];
177 while ((p = strsep(&data, ","))) {
183 token = match_token(p, tokens, args);
185 case Opt_override_compr:
186 name = match_strdup(&args[0]);
190 if (!strcmp(name, "none"))
191 c->mount_opts.compr = JFFS2_COMPR_MODE_NONE;
192 #ifdef CONFIG_JFFS2_LZO
193 else if (!strcmp(name, "lzo"))
194 c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO;
196 #ifdef CONFIG_JFFS2_ZLIB
197 else if (!strcmp(name, "zlib"))
198 c->mount_opts.compr =
199 JFFS2_COMPR_MODE_FORCEZLIB;
202 pr_err("Error: unknown compressor \"%s\"\n",
208 c->mount_opts.override_compr = true;
211 pr_err("Error: unrecognized mount option '%s' or missing value\n",
220 static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
222 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
225 err = jffs2_parse_options(c, data);
229 return jffs2_do_remount_fs(sb, flags, data);
232 static const struct super_operations jffs2_super_operations =
234 .alloc_inode = jffs2_alloc_inode,
235 .destroy_inode =jffs2_destroy_inode,
236 .put_super = jffs2_put_super,
237 .statfs = jffs2_statfs,
238 .remount_fs = jffs2_remount_fs,
239 .evict_inode = jffs2_evict_inode,
240 .dirty_inode = jffs2_dirty_inode,
241 .show_options = jffs2_show_options,
242 .sync_fs = jffs2_sync_fs,
246 * fill in the superblock
248 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
250 struct jffs2_sb_info *c;
253 jffs2_dbg(1, "jffs2_get_sb_mtd():"
254 " New superblock for device %d (\"%s\")\n",
255 sb->s_mtd->index, sb->s_mtd->name);
257 c = kzalloc(sizeof(*c), GFP_KERNEL);
265 ret = jffs2_parse_options(c, data);
271 /* Initialize JFFS2 superblock locks, the further initialization will
273 mutex_init(&c->alloc_sem);
274 mutex_init(&c->erase_free_sem);
275 init_waitqueue_head(&c->erase_wait);
276 init_waitqueue_head(&c->inocache_wq);
277 spin_lock_init(&c->erase_completion_lock);
278 spin_lock_init(&c->inocache_lock);
280 sb->s_op = &jffs2_super_operations;
281 sb->s_export_op = &jffs2_export_ops;
282 sb->s_flags = sb->s_flags | MS_NOATIME;
283 sb->s_xattr = jffs2_xattr_handlers;
284 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
285 sb->s_flags |= MS_POSIXACL;
287 ret = jffs2_do_fill_super(sb, data, silent);
291 static struct dentry *jffs2_mount(struct file_system_type *fs_type,
292 int flags, const char *dev_name,
295 return mount_mtd(fs_type, flags, dev_name, data, jffs2_fill_super);
298 static void jffs2_put_super (struct super_block *sb)
300 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
302 jffs2_dbg(2, "%s()\n", __func__);
304 mutex_lock(&c->alloc_sem);
305 jffs2_flush_wbuf_pad(c);
306 mutex_unlock(&c->alloc_sem);
310 jffs2_free_ino_caches(c);
311 jffs2_free_raw_node_refs(c);
312 if (jffs2_blocks_use_vmalloc(c))
316 jffs2_flash_cleanup(c);
317 kfree(c->inocache_list);
318 jffs2_clear_xattr_subsystem(c);
320 jffs2_dbg(1, "%s(): returning\n", __func__);
323 static void jffs2_kill_sb(struct super_block *sb)
325 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
326 if (!(sb->s_flags & MS_RDONLY))
327 jffs2_stop_garbage_collect_thread(c);
332 static struct file_system_type jffs2_fs_type = {
333 .owner = THIS_MODULE,
335 .mount = jffs2_mount,
336 .kill_sb = jffs2_kill_sb,
339 static int __init init_jffs2_fs(void)
343 /* Paranoia checks for on-medium structures. If we ask GCC
344 to pack them with __attribute__((packed)) then it _also_
345 assumes that they're not aligned -- so it emits crappy
346 code on some architectures. Ideally we want an attribute
347 which means just 'no padding', without the alignment
348 thing. But GCC doesn't have that -- we have to just
349 hope the structs are the right sizes, instead. */
350 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
351 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
352 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
353 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
355 pr_info("version 2.2."
356 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
359 #ifdef CONFIG_JFFS2_SUMMARY
362 " © 2001-2006 Red Hat, Inc.\n");
364 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
365 sizeof(struct jffs2_inode_info),
366 0, (SLAB_RECLAIM_ACCOUNT|
369 if (!jffs2_inode_cachep) {
370 pr_err("error: Failed to initialise inode cache\n");
373 ret = jffs2_compressors_init();
375 pr_err("error: Failed to initialise compressors\n");
378 ret = jffs2_create_slab_caches();
380 pr_err("error: Failed to initialise slab caches\n");
381 goto out_compressors;
383 ret = register_filesystem(&jffs2_fs_type);
385 pr_err("error: Failed to register filesystem\n");
391 jffs2_destroy_slab_caches();
393 jffs2_compressors_exit();
395 kmem_cache_destroy(jffs2_inode_cachep);
399 static void __exit exit_jffs2_fs(void)
401 unregister_filesystem(&jffs2_fs_type);
402 jffs2_destroy_slab_caches();
403 jffs2_compressors_exit();
404 kmem_cache_destroy(jffs2_inode_cachep);
407 module_init(init_jffs2_fs);
408 module_exit(exit_jffs2_fs);
410 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
411 MODULE_AUTHOR("Red Hat, Inc.");
412 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
413 // the sake of this tag. It's Free Software.