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
);
73 if (!(sb
->s_flags
& MS_RDONLY
)) {
74 jffs2_dbg(1, "%s()\n", __func__
);
75 jffs2_flush_wbuf_gc(c
, 0);
81 static const char *jffs2_compr_name(unsigned int compr
)
84 case JFFS2_COMPR_MODE_NONE
:
86 #ifdef CONFIG_JFFS2_LZO
87 case JFFS2_COMPR_MODE_FORCELZO
:
90 #ifdef CONFIG_JFFS2_ZLIB
91 case JFFS2_COMPR_MODE_FORCEZLIB
:
95 /* should never happen; programmer error */
101 static int jffs2_show_options(struct seq_file
*s
, struct dentry
*root
)
103 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(root
->d_sb
);
104 struct jffs2_mount_opts
*opts
= &c
->mount_opts
;
106 if (opts
->override_compr
)
107 seq_printf(s
, ",compr=%s", jffs2_compr_name(opts
->compr
));
112 static int jffs2_sync_fs(struct super_block
*sb
, int wait
)
114 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
116 jffs2_write_super(sb
);
118 mutex_lock(&c
->alloc_sem
);
119 jffs2_flush_wbuf_pad(c
);
120 mutex_unlock(&c
->alloc_sem
);
124 static struct inode
*jffs2_nfs_get_inode(struct super_block
*sb
, uint64_t ino
,
127 /* We don't care about i_generation. We'll destroy the flash
128 before we start re-using inode numbers anyway. And even
129 if that wasn't true, we'd have other problems...*/
130 return jffs2_iget(sb
, ino
);
133 static struct dentry
*jffs2_fh_to_dentry(struct super_block
*sb
, struct fid
*fid
,
134 int fh_len
, int fh_type
)
136 return generic_fh_to_dentry(sb
, fid
, fh_len
, fh_type
,
137 jffs2_nfs_get_inode
);
140 static struct dentry
*jffs2_fh_to_parent(struct super_block
*sb
, struct fid
*fid
,
141 int fh_len
, int fh_type
)
143 return generic_fh_to_parent(sb
, fid
, fh_len
, fh_type
,
144 jffs2_nfs_get_inode
);
147 static struct dentry
*jffs2_get_parent(struct dentry
*child
)
149 struct jffs2_inode_info
*f
;
152 BUG_ON(!S_ISDIR(child
->d_inode
->i_mode
));
154 f
= JFFS2_INODE_INFO(child
->d_inode
);
156 pino
= f
->inocache
->pino_nlink
;
158 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
159 f
->inocache
->ino
, pino
);
161 return d_obtain_alias(jffs2_iget(child
->d_inode
->i_sb
, pino
));
164 static const struct export_operations jffs2_export_ops
= {
165 .get_parent
= jffs2_get_parent
,
166 .fh_to_dentry
= jffs2_fh_to_dentry
,
167 .fh_to_parent
= jffs2_fh_to_parent
,
171 * JFFS2 mount options.
173 * Opt_override_compr: override default compressor
174 * Opt_err: just end of array marker
181 static const match_table_t tokens
= {
182 {Opt_override_compr
, "compr=%s"},
186 static int jffs2_parse_options(struct jffs2_sb_info
*c
, char *data
)
188 substring_t args
[MAX_OPT_ARGS
];
194 while ((p
= strsep(&data
, ","))) {
200 token
= match_token(p
, tokens
, args
);
202 case Opt_override_compr
:
203 name
= match_strdup(&args
[0]);
207 if (!strcmp(name
, "none"))
208 c
->mount_opts
.compr
= JFFS2_COMPR_MODE_NONE
;
209 #ifdef CONFIG_JFFS2_LZO
210 else if (!strcmp(name
, "lzo"))
211 c
->mount_opts
.compr
= JFFS2_COMPR_MODE_FORCELZO
;
213 #ifdef CONFIG_JFFS2_ZLIB
214 else if (!strcmp(name
, "zlib"))
215 c
->mount_opts
.compr
=
216 JFFS2_COMPR_MODE_FORCEZLIB
;
219 pr_err("Error: unknown compressor \"%s\"\n",
225 c
->mount_opts
.override_compr
= true;
228 pr_err("Error: unrecognized mount option '%s' or missing value\n",
237 static int jffs2_remount_fs(struct super_block
*sb
, int *flags
, char *data
)
239 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
242 err
= jffs2_parse_options(c
, data
);
246 return jffs2_do_remount_fs(sb
, flags
, data
);
249 static const struct super_operations jffs2_super_operations
=
251 .alloc_inode
= jffs2_alloc_inode
,
252 .destroy_inode
=jffs2_destroy_inode
,
253 .put_super
= jffs2_put_super
,
254 .write_super
= jffs2_write_super
,
255 .statfs
= jffs2_statfs
,
256 .remount_fs
= jffs2_remount_fs
,
257 .evict_inode
= jffs2_evict_inode
,
258 .dirty_inode
= jffs2_dirty_inode
,
259 .show_options
= jffs2_show_options
,
260 .sync_fs
= jffs2_sync_fs
,
264 * fill in the superblock
266 static int jffs2_fill_super(struct super_block
*sb
, void *data
, int silent
)
268 struct jffs2_sb_info
*c
;
271 jffs2_dbg(1, "jffs2_get_sb_mtd():"
272 " New superblock for device %d (\"%s\")\n",
273 sb
->s_mtd
->index
, sb
->s_mtd
->name
);
275 c
= kzalloc(sizeof(*c
), GFP_KERNEL
);
283 ret
= jffs2_parse_options(c
, data
);
289 /* Initialize JFFS2 superblock locks, the further initialization will
291 mutex_init(&c
->alloc_sem
);
292 mutex_init(&c
->erase_free_sem
);
293 init_waitqueue_head(&c
->erase_wait
);
294 init_waitqueue_head(&c
->inocache_wq
);
295 spin_lock_init(&c
->erase_completion_lock
);
296 spin_lock_init(&c
->inocache_lock
);
298 sb
->s_op
= &jffs2_super_operations
;
299 sb
->s_export_op
= &jffs2_export_ops
;
300 sb
->s_flags
= sb
->s_flags
| MS_NOATIME
;
301 sb
->s_xattr
= jffs2_xattr_handlers
;
302 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
303 sb
->s_flags
|= MS_POSIXACL
;
305 ret
= jffs2_do_fill_super(sb
, data
, silent
);
309 static struct dentry
*jffs2_mount(struct file_system_type
*fs_type
,
310 int flags
, const char *dev_name
,
313 return mount_mtd(fs_type
, flags
, dev_name
, data
, jffs2_fill_super
);
316 static void jffs2_put_super (struct super_block
*sb
)
318 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
320 jffs2_dbg(2, "%s()\n", __func__
);
323 jffs2_write_super(sb
);
325 mutex_lock(&c
->alloc_sem
);
326 jffs2_flush_wbuf_pad(c
);
327 mutex_unlock(&c
->alloc_sem
);
331 jffs2_free_ino_caches(c
);
332 jffs2_free_raw_node_refs(c
);
333 if (jffs2_blocks_use_vmalloc(c
))
337 jffs2_flash_cleanup(c
);
338 kfree(c
->inocache_list
);
339 jffs2_clear_xattr_subsystem(c
);
341 jffs2_dbg(1, "%s(): returning\n", __func__
);
344 static void jffs2_kill_sb(struct super_block
*sb
)
346 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
347 if (!(sb
->s_flags
& MS_RDONLY
))
348 jffs2_stop_garbage_collect_thread(c
);
353 static struct file_system_type jffs2_fs_type
= {
354 .owner
= THIS_MODULE
,
356 .mount
= jffs2_mount
,
357 .kill_sb
= jffs2_kill_sb
,
360 static int __init
init_jffs2_fs(void)
364 /* Paranoia checks for on-medium structures. If we ask GCC
365 to pack them with __attribute__((packed)) then it _also_
366 assumes that they're not aligned -- so it emits crappy
367 code on some architectures. Ideally we want an attribute
368 which means just 'no padding', without the alignment
369 thing. But GCC doesn't have that -- we have to just
370 hope the structs are the right sizes, instead. */
371 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node
) != 12);
372 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent
) != 40);
373 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode
) != 68);
374 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary
) != 32);
376 pr_info("version 2.2."
377 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
380 #ifdef CONFIG_JFFS2_SUMMARY
383 " © 2001-2006 Red Hat, Inc.\n");
385 jffs2_inode_cachep
= kmem_cache_create("jffs2_i",
386 sizeof(struct jffs2_inode_info
),
387 0, (SLAB_RECLAIM_ACCOUNT
|
390 if (!jffs2_inode_cachep
) {
391 pr_err("error: Failed to initialise inode cache\n");
394 ret
= jffs2_compressors_init();
396 pr_err("error: Failed to initialise compressors\n");
399 ret
= jffs2_create_slab_caches();
401 pr_err("error: Failed to initialise slab caches\n");
402 goto out_compressors
;
404 ret
= register_filesystem(&jffs2_fs_type
);
406 pr_err("error: Failed to register filesystem\n");
412 jffs2_destroy_slab_caches();
414 jffs2_compressors_exit();
416 kmem_cache_destroy(jffs2_inode_cachep
);
420 static void __exit
exit_jffs2_fs(void)
422 unregister_filesystem(&jffs2_fs_type
);
423 jffs2_destroy_slab_caches();
424 jffs2_compressors_exit();
425 kmem_cache_destroy(jffs2_inode_cachep
);
428 module_init(init_jffs2_fs
);
429 module_exit(exit_jffs2_fs
);
431 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
432 MODULE_AUTHOR("Red Hat, Inc.");
433 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
434 // the sake of this tag. It's Free Software.