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 void jffs2_write_super(struct super_block *sb)
68 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
72 if (!(sb->s_flags & MS_RDONLY)) {
73 jffs2_dbg(1, "%s()\n", __func__);
74 jffs2_flush_wbuf_gc(c, 0);
78 static const char *jffs2_compr_name(unsigned int compr)
81 case JFFS2_COMPR_MODE_NONE:
83 #ifdef CONFIG_JFFS2_LZO
84 case JFFS2_COMPR_MODE_FORCELZO:
87 #ifdef CONFIG_JFFS2_ZLIB
88 case JFFS2_COMPR_MODE_FORCEZLIB:
92 /* should never happen; programmer error */
98 static int jffs2_show_options(struct seq_file *s, struct dentry *root)
100 struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb);
101 struct jffs2_mount_opts *opts = &c->mount_opts;
103 if (opts->override_compr)
104 seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
106 seq_printf(s, ",rp_size=%u", opts->rp_size / 1024);
111 static int jffs2_sync_fs(struct super_block *sb, int wait)
113 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
115 jffs2_write_super(sb);
117 mutex_lock(&c->alloc_sem);
118 jffs2_flush_wbuf_pad(c);
119 mutex_unlock(&c->alloc_sem);
123 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
126 /* We don't care about i_generation. We'll destroy the flash
127 before we start re-using inode numbers anyway. And even
128 if that wasn't true, we'd have other problems...*/
129 return jffs2_iget(sb, ino);
132 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
133 int fh_len, int fh_type)
135 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
136 jffs2_nfs_get_inode);
139 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
140 int fh_len, int fh_type)
142 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
143 jffs2_nfs_get_inode);
146 static struct dentry *jffs2_get_parent(struct dentry *child)
148 struct jffs2_inode_info *f;
151 BUG_ON(!S_ISDIR(child->d_inode->i_mode));
153 f = JFFS2_INODE_INFO(child->d_inode);
155 pino = f->inocache->pino_nlink;
157 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
158 f->inocache->ino, pino);
160 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
163 static const struct export_operations jffs2_export_ops = {
164 .get_parent = jffs2_get_parent,
165 .fh_to_dentry = jffs2_fh_to_dentry,
166 .fh_to_parent = jffs2_fh_to_parent,
170 * JFFS2 mount options.
172 * Opt_override_compr: override default compressor
173 * Opt_rp_size: size of reserved pool in KiB
174 * Opt_err: just end of array marker
182 static const match_table_t tokens = {
183 {Opt_override_compr, "compr=%s"},
184 {Opt_rp_size, "rp_size=%u"},
188 static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
190 substring_t args[MAX_OPT_ARGS];
197 while ((p = strsep(&data, ","))) {
203 token = match_token(p, tokens, args);
205 case Opt_override_compr:
206 name = match_strdup(&args[0]);
210 if (!strcmp(name, "none"))
211 c->mount_opts.compr = JFFS2_COMPR_MODE_NONE;
212 #ifdef CONFIG_JFFS2_LZO
213 else if (!strcmp(name, "lzo"))
214 c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO;
216 #ifdef CONFIG_JFFS2_ZLIB
217 else if (!strcmp(name, "zlib"))
218 c->mount_opts.compr =
219 JFFS2_COMPR_MODE_FORCEZLIB;
222 pr_err("Error: unknown compressor \"%s\"\n",
228 c->mount_opts.override_compr = true;
231 if (match_int(&args[0], &opt))
234 if (opt > c->mtd->size) {
235 pr_warn("Too large reserve pool specified, max "
236 "is %llu KB\n", c->mtd->size / 1024);
239 c->mount_opts.rp_size = opt;
242 pr_err("Error: unrecognized mount option '%s' or missing value\n",
251 static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
253 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
256 err = jffs2_parse_options(c, data);
260 return jffs2_do_remount_fs(sb, flags, data);
263 static const struct super_operations jffs2_super_operations =
265 .alloc_inode = jffs2_alloc_inode,
266 .destroy_inode =jffs2_destroy_inode,
267 .put_super = jffs2_put_super,
268 .write_super = jffs2_write_super,
269 .statfs = jffs2_statfs,
270 .remount_fs = jffs2_remount_fs,
271 .evict_inode = jffs2_evict_inode,
272 .dirty_inode = jffs2_dirty_inode,
273 .show_options = jffs2_show_options,
274 .sync_fs = jffs2_sync_fs,
278 * fill in the superblock
280 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
282 struct jffs2_sb_info *c;
285 jffs2_dbg(1, "jffs2_get_sb_mtd():"
286 " New superblock for device %d (\"%s\")\n",
287 sb->s_mtd->index, sb->s_mtd->name);
289 c = kzalloc(sizeof(*c), GFP_KERNEL);
297 ret = jffs2_parse_options(c, data);
303 /* Initialize JFFS2 superblock locks, the further initialization will
305 mutex_init(&c->alloc_sem);
306 mutex_init(&c->erase_free_sem);
307 init_waitqueue_head(&c->erase_wait);
308 init_waitqueue_head(&c->inocache_wq);
309 spin_lock_init(&c->erase_completion_lock);
310 spin_lock_init(&c->inocache_lock);
312 sb->s_op = &jffs2_super_operations;
313 sb->s_export_op = &jffs2_export_ops;
314 sb->s_flags = sb->s_flags | MS_NOATIME;
315 sb->s_xattr = jffs2_xattr_handlers;
316 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
317 sb->s_flags |= MS_POSIXACL;
319 ret = jffs2_do_fill_super(sb, data, silent);
323 static struct dentry *jffs2_mount(struct file_system_type *fs_type,
324 int flags, const char *dev_name,
327 return mount_mtd(fs_type, flags, dev_name, data, jffs2_fill_super);
330 static void jffs2_put_super (struct super_block *sb)
332 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
334 jffs2_dbg(2, "%s()\n", __func__);
337 jffs2_write_super(sb);
339 mutex_lock(&c->alloc_sem);
340 jffs2_flush_wbuf_pad(c);
341 mutex_unlock(&c->alloc_sem);
345 jffs2_free_ino_caches(c);
346 jffs2_free_raw_node_refs(c);
347 if (jffs2_blocks_use_vmalloc(c))
351 jffs2_flash_cleanup(c);
352 kfree(c->inocache_list);
353 jffs2_clear_xattr_subsystem(c);
355 jffs2_dbg(1, "%s(): returning\n", __func__);
358 static void jffs2_kill_sb(struct super_block *sb)
360 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
361 if (!(sb->s_flags & MS_RDONLY))
362 jffs2_stop_garbage_collect_thread(c);
367 static struct file_system_type jffs2_fs_type = {
368 .owner = THIS_MODULE,
370 .mount = jffs2_mount,
371 .kill_sb = jffs2_kill_sb,
374 static int __init init_jffs2_fs(void)
378 /* Paranoia checks for on-medium structures. If we ask GCC
379 to pack them with __attribute__((packed)) then it _also_
380 assumes that they're not aligned -- so it emits crappy
381 code on some architectures. Ideally we want an attribute
382 which means just 'no padding', without the alignment
383 thing. But GCC doesn't have that -- we have to just
384 hope the structs are the right sizes, instead. */
385 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
386 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
387 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
388 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
390 pr_info("version 2.2."
391 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
394 #ifdef CONFIG_JFFS2_SUMMARY
397 " © 2001-2006 Red Hat, Inc.\n");
399 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
400 sizeof(struct jffs2_inode_info),
401 0, (SLAB_RECLAIM_ACCOUNT|
404 if (!jffs2_inode_cachep) {
405 pr_err("error: Failed to initialise inode cache\n");
408 ret = jffs2_compressors_init();
410 pr_err("error: Failed to initialise compressors\n");
413 ret = jffs2_create_slab_caches();
415 pr_err("error: Failed to initialise slab caches\n");
416 goto out_compressors;
418 ret = register_filesystem(&jffs2_fs_type);
420 pr_err("error: Failed to register filesystem\n");
426 jffs2_destroy_slab_caches();
428 jffs2_compressors_exit();
430 kmem_cache_destroy(jffs2_inode_cachep);
434 static void __exit exit_jffs2_fs(void)
436 unregister_filesystem(&jffs2_fs_type);
437 jffs2_destroy_slab_caches();
438 jffs2_compressors_exit();
439 kmem_cache_destroy(jffs2_inode_cachep);
442 module_init(init_jffs2_fs);
443 module_exit(exit_jffs2_fs);
445 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
446 MODULE_AUTHOR("Red Hat, Inc.");
447 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
448 // the sake of this tag. It's Free Software.