2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright (C) 2001-2003 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@infradead.org>
8 * For licensing information, see the file 'LICENCE' in this directory.
10 * $Id: super.c,v 1.110 2005/11/07 11:14:42 gleixner Exp $
14 #include <linux/config.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/init.h>
19 #include <linux/list.h>
21 #include <linux/mount.h>
22 #include <linux/jffs2.h>
23 #include <linux/pagemap.h>
24 #include <linux/mtd/mtd.h>
25 #include <linux/ctype.h>
26 #include <linux/namei.h>
30 static void jffs2_put_super(struct super_block
*);
32 static kmem_cache_t
*jffs2_inode_cachep
;
34 static struct inode
*jffs2_alloc_inode(struct super_block
*sb
)
36 struct jffs2_inode_info
*ei
;
37 ei
= (struct jffs2_inode_info
*)kmem_cache_alloc(jffs2_inode_cachep
, SLAB_KERNEL
);
40 return &ei
->vfs_inode
;
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
, kmem_cache_t
* cachep
, unsigned long flags
)
50 struct jffs2_inode_info
*ei
= (struct jffs2_inode_info
*) foo
;
52 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
53 SLAB_CTOR_CONSTRUCTOR
) {
55 inode_init_once(&ei
->vfs_inode
);
59 static int jffs2_sync_fs(struct super_block
*sb
, int wait
)
61 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
64 jffs2_flush_wbuf_pad(c
);
69 static struct super_operations jffs2_super_operations
=
71 .alloc_inode
= jffs2_alloc_inode
,
72 .destroy_inode
=jffs2_destroy_inode
,
73 .read_inode
= jffs2_read_inode
,
74 .put_super
= jffs2_put_super
,
75 .write_super
= jffs2_write_super
,
76 .statfs
= jffs2_statfs
,
77 .remount_fs
= jffs2_remount_fs
,
78 .clear_inode
= jffs2_clear_inode
,
79 .dirty_inode
= jffs2_dirty_inode
,
80 .sync_fs
= jffs2_sync_fs
,
83 static int jffs2_sb_compare(struct super_block
*sb
, void *data
)
85 struct jffs2_sb_info
*p
= data
;
86 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
88 /* The superblocks are considered to be equivalent if the underlying MTD
89 device is the same one */
90 if (c
->mtd
== p
->mtd
) {
91 D1(printk(KERN_DEBUG
"jffs2_sb_compare: match on device %d (\"%s\")\n", p
->mtd
->index
, p
->mtd
->name
));
94 D1(printk(KERN_DEBUG
"jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n",
95 c
->mtd
->index
, c
->mtd
->name
, p
->mtd
->index
, p
->mtd
->name
));
100 static int jffs2_sb_set(struct super_block
*sb
, void *data
)
102 struct jffs2_sb_info
*p
= data
;
104 /* For persistence of NFS exports etc. we use the same s_dev
105 each time we mount the device, don't just use an anonymous
109 sb
->s_dev
= MKDEV(MTD_BLOCK_MAJOR
, p
->mtd
->index
);
114 static int jffs2_get_sb_mtd(struct file_system_type
*fs_type
,
115 int flags
, const char *dev_name
,
116 void *data
, struct mtd_info
*mtd
,
117 struct vfsmount
*mnt
)
119 struct super_block
*sb
;
120 struct jffs2_sb_info
*c
;
123 c
= kmalloc(sizeof(*c
), GFP_KERNEL
);
126 memset(c
, 0, sizeof(*c
));
129 sb
= sget(fs_type
, jffs2_sb_compare
, jffs2_sb_set
, c
);
135 /* New mountpoint for JFFS2 which is already mounted */
136 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n",
137 mtd
->index
, mtd
->name
));
138 ret
= simple_set_mnt(mnt
, sb
);
142 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n",
143 mtd
->index
, mtd
->name
));
145 /* Initialize JFFS2 superblock locks, the further initialization will be
147 init_MUTEX(&c
->alloc_sem
);
148 init_MUTEX(&c
->erase_free_sem
);
149 init_waitqueue_head(&c
->erase_wait
);
150 init_waitqueue_head(&c
->inocache_wq
);
151 spin_lock_init(&c
->erase_completion_lock
);
152 spin_lock_init(&c
->inocache_lock
);
154 sb
->s_op
= &jffs2_super_operations
;
155 sb
->s_flags
= flags
| MS_NOATIME
;
156 sb
->s_xattr
= jffs2_xattr_handlers
;
157 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
158 sb
->s_flags
|= MS_POSIXACL
;
160 ret
= jffs2_do_fill_super(sb
, data
, flags
& MS_SILENT
? 1 : 0);
163 /* Failure case... */
164 up_write(&sb
->s_umount
);
165 deactivate_super(sb
);
169 sb
->s_flags
|= MS_ACTIVE
;
170 return simple_set_mnt(mnt
, sb
);
181 static int jffs2_get_sb_mtdnr(struct file_system_type
*fs_type
,
182 int flags
, const char *dev_name
,
183 void *data
, int mtdnr
,
184 struct vfsmount
*mnt
)
186 struct mtd_info
*mtd
;
188 mtd
= get_mtd_device(NULL
, mtdnr
);
190 D1(printk(KERN_DEBUG
"jffs2: MTD device #%u doesn't appear to exist\n", mtdnr
));
194 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
, mnt
);
197 static int jffs2_get_sb(struct file_system_type
*fs_type
,
198 int flags
, const char *dev_name
,
199 void *data
, struct vfsmount
*mnt
)
208 D1(printk(KERN_DEBUG
"jffs2_get_sb(): dev_name \"%s\"\n", dev_name
));
210 /* The preferred way of mounting in future; especially when
211 CONFIG_BLK_DEV is implemented - we specify the underlying
212 MTD device by number or by name, so that we don't require
213 block device support to be present in the kernel. */
215 /* FIXME: How to do the root fs this way? */
217 if (dev_name
[0] == 'm' && dev_name
[1] == 't' && dev_name
[2] == 'd') {
218 /* Probably mounting without the blkdev crap */
219 if (dev_name
[3] == ':') {
220 struct mtd_info
*mtd
;
222 /* Mount by MTD device name */
223 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name
+4));
224 for (mtdnr
= 0; mtdnr
< MAX_MTD_DEVICES
; mtdnr
++) {
225 mtd
= get_mtd_device(NULL
, mtdnr
);
227 if (!strcmp(mtd
->name
, dev_name
+4))
228 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
, mnt
);
232 printk(KERN_NOTICE
"jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name
+4);
233 } else if (isdigit(dev_name
[3])) {
234 /* Mount by MTD device number name */
237 mtdnr
= simple_strtoul(dev_name
+3, &endptr
, 0);
239 /* It was a valid number */
240 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr
));
241 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
, mnt
);
246 /* Try the old way - the hack where we allowed users to mount
247 /dev/mtdblock$(n) but didn't actually _use_ the blkdev */
249 err
= path_lookup(dev_name
, LOOKUP_FOLLOW
, &nd
);
251 D1(printk(KERN_DEBUG
"jffs2_get_sb(): path_lookup() returned %d, inode %p\n",
252 err
, nd
.dentry
->d_inode
));
259 if (!S_ISBLK(nd
.dentry
->d_inode
->i_mode
))
262 if (nd
.mnt
->mnt_flags
& MNT_NODEV
) {
267 if (imajor(nd
.dentry
->d_inode
) != MTD_BLOCK_MAJOR
) {
268 if (!(flags
& MS_SILENT
))
269 printk(KERN_NOTICE
"Attempt to mount non-MTD device \"%s\" as JFFS2\n",
274 mtdnr
= iminor(nd
.dentry
->d_inode
);
277 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
, mnt
);
284 static void jffs2_put_super (struct super_block
*sb
)
286 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
288 D2(printk(KERN_DEBUG
"jffs2: jffs2_put_super()\n"));
291 jffs2_flush_wbuf_pad(c
);
296 jffs2_free_ino_caches(c
);
297 jffs2_free_raw_node_refs(c
);
298 if (jffs2_blocks_use_vmalloc(c
))
302 jffs2_flash_cleanup(c
);
303 kfree(c
->inocache_list
);
304 jffs2_clear_xattr_subsystem(c
);
306 c
->mtd
->sync(c
->mtd
);
308 D1(printk(KERN_DEBUG
"jffs2_put_super returning\n"));
311 static void jffs2_kill_sb(struct super_block
*sb
)
313 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
314 if (!(sb
->s_flags
& MS_RDONLY
))
315 jffs2_stop_garbage_collect_thread(c
);
316 generic_shutdown_super(sb
);
317 put_mtd_device(c
->mtd
);
321 static struct file_system_type jffs2_fs_type
= {
322 .owner
= THIS_MODULE
,
324 .get_sb
= jffs2_get_sb
,
325 .kill_sb
= jffs2_kill_sb
,
328 static int __init
init_jffs2_fs(void)
332 /* Paranoia checks for on-medium structures. If we ask GCC
333 to pack them with __attribute__((packed)) then it _also_
334 assumes that they're not aligned -- so it emits crappy
335 code on some architectures. Ideally we want an attribute
336 which means just 'no padding', without the alignment
337 thing. But GCC doesn't have that -- we have to just
338 hope the structs are the right sizes, instead. */
339 BUG_ON(sizeof(struct jffs2_unknown_node
) != 12);
340 BUG_ON(sizeof(struct jffs2_raw_dirent
) != 40);
341 BUG_ON(sizeof(struct jffs2_raw_inode
) != 68);
342 BUG_ON(sizeof(struct jffs2_raw_summary
) != 32);
344 printk(KERN_INFO
"JFFS2 version 2.2."
345 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
348 #ifdef CONFIG_JFFS2_SUMMARY
351 " (C) 2001-2006 Red Hat, Inc.\n");
353 jffs2_inode_cachep
= kmem_cache_create("jffs2_i",
354 sizeof(struct jffs2_inode_info
),
355 0, (SLAB_RECLAIM_ACCOUNT
|
357 jffs2_i_init_once
, NULL
);
358 if (!jffs2_inode_cachep
) {
359 printk(KERN_ERR
"JFFS2 error: Failed to initialise inode cache\n");
362 ret
= jffs2_compressors_init();
364 printk(KERN_ERR
"JFFS2 error: Failed to initialise compressors\n");
367 ret
= jffs2_create_slab_caches();
369 printk(KERN_ERR
"JFFS2 error: Failed to initialise slab caches\n");
370 goto out_compressors
;
372 ret
= register_filesystem(&jffs2_fs_type
);
374 printk(KERN_ERR
"JFFS2 error: Failed to register filesystem\n");
380 jffs2_destroy_slab_caches();
382 jffs2_compressors_exit();
384 kmem_cache_destroy(jffs2_inode_cachep
);
388 static void __exit
exit_jffs2_fs(void)
390 unregister_filesystem(&jffs2_fs_type
);
391 jffs2_destroy_slab_caches();
392 jffs2_compressors_exit();
393 kmem_cache_destroy(jffs2_inode_cachep
);
396 module_init(init_jffs2_fs
);
397 module_exit(exit_jffs2_fs
);
399 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
400 MODULE_AUTHOR("Red Hat, Inc.");
401 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
402 // the sake of this tag. It's Free Software.