2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright (C) 2001-2003 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@redhat.com>
8 * For licensing information, see the file 'LICENCE' in this directory.
10 * $Id: super.c,v 1.90 2003/10/11 11:47:23 dwmw2 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>
29 static void jffs2_put_super(struct super_block
*);
31 static kmem_cache_t
*jffs2_inode_cachep
;
33 static struct inode
*jffs2_alloc_inode(struct super_block
*sb
)
35 struct jffs2_inode_info
*ei
;
36 ei
= (struct jffs2_inode_info
*)kmem_cache_alloc(jffs2_inode_cachep
, SLAB_KERNEL
);
39 return &ei
->vfs_inode
;
42 static void jffs2_destroy_inode(struct inode
*inode
)
44 kmem_cache_free(jffs2_inode_cachep
, JFFS2_INODE_INFO(inode
));
47 static void jffs2_i_init_once(void * foo
, kmem_cache_t
* cachep
, unsigned long flags
)
49 struct jffs2_inode_info
*ei
= (struct jffs2_inode_info
*) foo
;
51 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
52 SLAB_CTOR_CONSTRUCTOR
) {
53 init_MUTEX_LOCKED(&ei
->sem
);
54 inode_init_once(&ei
->vfs_inode
);
58 static struct super_operations jffs2_super_operations
=
60 .alloc_inode
= jffs2_alloc_inode
,
61 .destroy_inode
=jffs2_destroy_inode
,
62 .read_inode
= jffs2_read_inode
,
63 .put_super
= jffs2_put_super
,
64 .write_super
= jffs2_write_super
,
65 .statfs
= jffs2_statfs
,
66 .remount_fs
= jffs2_remount_fs
,
67 .clear_inode
= jffs2_clear_inode
,
68 .dirty_inode
= jffs2_dirty_inode
,
71 static int jffs2_sb_compare(struct super_block
*sb
, void *data
)
73 struct jffs2_sb_info
*p
= data
;
74 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
76 /* The superblocks are considered to be equivalent if the underlying MTD
77 device is the same one */
78 if (c
->mtd
== p
->mtd
) {
79 D1(printk(KERN_DEBUG
"jffs2_sb_compare: match on device %d (\"%s\")\n", p
->mtd
->index
, p
->mtd
->name
));
82 D1(printk(KERN_DEBUG
"jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n",
83 c
->mtd
->index
, c
->mtd
->name
, p
->mtd
->index
, p
->mtd
->name
));
88 static int jffs2_sb_set(struct super_block
*sb
, void *data
)
90 struct jffs2_sb_info
*p
= data
;
92 /* For persistence of NFS exports etc. we use the same s_dev
93 each time we mount the device, don't just use an anonymous
97 sb
->s_dev
= MKDEV(MTD_BLOCK_MAJOR
, p
->mtd
->index
);
102 static struct super_block
*jffs2_get_sb_mtd(struct file_system_type
*fs_type
,
103 int flags
, const char *dev_name
,
104 void *data
, struct mtd_info
*mtd
)
106 struct super_block
*sb
;
107 struct jffs2_sb_info
*c
;
110 c
= kmalloc(sizeof(*c
), GFP_KERNEL
);
112 return ERR_PTR(-ENOMEM
);
113 memset(c
, 0, sizeof(*c
));
116 sb
= sget(fs_type
, jffs2_sb_compare
, jffs2_sb_set
, c
);
122 /* New mountpoint for JFFS2 which is already mounted */
123 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n",
124 mtd
->index
, mtd
->name
));
128 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n",
129 mtd
->index
, mtd
->name
));
131 sb
->s_op
= &jffs2_super_operations
;
132 sb
->s_flags
|= MS_NOATIME
;
134 ret
= jffs2_do_fill_super(sb
, data
, (flags
&MS_VERBOSE
)?1:0);
137 /* Failure case... */
138 up_write(&sb
->s_umount
);
139 deactivate_super(sb
);
143 sb
->s_flags
|= MS_ACTIVE
;
153 static struct super_block
*jffs2_get_sb_mtdnr(struct file_system_type
*fs_type
,
154 int flags
, const char *dev_name
,
155 void *data
, int mtdnr
)
157 struct mtd_info
*mtd
;
159 mtd
= get_mtd_device(NULL
, mtdnr
);
161 D1(printk(KERN_DEBUG
"jffs2: MTD device #%u doesn't appear to exist\n", mtdnr
));
162 return ERR_PTR(-EINVAL
);
165 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
);
168 static struct super_block
*jffs2_get_sb(struct file_system_type
*fs_type
,
169 int flags
, const char *dev_name
,
177 return ERR_PTR(-EINVAL
);
179 D1(printk(KERN_DEBUG
"jffs2_get_sb(): dev_name \"%s\"\n", dev_name
));
181 /* The preferred way of mounting in future; especially when
182 CONFIG_BLK_DEV is implemented - we specify the underlying
183 MTD device by number or by name, so that we don't require
184 block device support to be present in the kernel. */
186 /* FIXME: How to do the root fs this way? */
188 if (dev_name
[0] == 'm' && dev_name
[1] == 't' && dev_name
[2] == 'd') {
189 /* Probably mounting without the blkdev crap */
190 if (dev_name
[3] == ':') {
191 struct mtd_info
*mtd
;
193 /* Mount by MTD device name */
194 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name
+4));
195 for (mtdnr
= 0; mtdnr
< MAX_MTD_DEVICES
; mtdnr
++) {
196 mtd
= get_mtd_device(NULL
, mtdnr
);
198 if (!strcmp(mtd
->name
, dev_name
+4))
199 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
);
203 printk(KERN_NOTICE
"jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name
+4);
204 } else if (isdigit(dev_name
[3])) {
205 /* Mount by MTD device number name */
208 mtdnr
= simple_strtoul(dev_name
+3, &endptr
, 0);
210 /* It was a valid number */
211 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr
));
212 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
);
217 /* Try the old way - the hack where we allowed users to mount
218 /dev/mtdblock$(n) but didn't actually _use_ the blkdev */
220 err
= path_lookup(dev_name
, LOOKUP_FOLLOW
, &nd
);
222 D1(printk(KERN_DEBUG
"jffs2_get_sb(): path_lookup() returned %d, inode %p\n",
223 err
, nd
.dentry
->d_inode
));
230 if (!S_ISBLK(nd
.dentry
->d_inode
->i_mode
))
233 if (nd
.mnt
->mnt_flags
& MNT_NODEV
) {
238 if (imajor(nd
.dentry
->d_inode
) != MTD_BLOCK_MAJOR
) {
239 if (!(flags
& MS_VERBOSE
)) /* Yes I mean this. Strangely */
240 printk(KERN_NOTICE
"Attempt to mount non-MTD device \"%s\" as JFFS2\n",
245 mtdnr
= iminor(nd
.dentry
->d_inode
);
248 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
);
255 static void jffs2_put_super (struct super_block
*sb
)
257 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
259 D2(printk(KERN_DEBUG
"jffs2: jffs2_put_super()\n"));
261 if (!(sb
->s_flags
& MS_RDONLY
))
262 jffs2_stop_garbage_collect_thread(c
);
264 jffs2_flush_wbuf_pad(c
);
266 jffs2_free_ino_caches(c
);
267 jffs2_free_raw_node_refs(c
);
269 jffs2_nand_flash_cleanup(c
);
270 kfree(c
->inocache_list
);
272 c
->mtd
->sync(c
->mtd
);
274 D1(printk(KERN_DEBUG
"jffs2_put_super returning\n"));
277 static void jffs2_kill_sb(struct super_block
*sb
)
279 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
280 generic_shutdown_super(sb
);
281 put_mtd_device(c
->mtd
);
285 static struct file_system_type jffs2_fs_type
= {
286 .owner
= THIS_MODULE
,
288 .get_sb
= jffs2_get_sb
,
289 .kill_sb
= jffs2_kill_sb
,
292 static int __init
init_jffs2_fs(void)
296 printk(KERN_INFO
"JFFS2 version 2.2."
297 #ifdef CONFIG_FS_JFFS2_NAND
300 " (C) 2001-2003 Red Hat, Inc.\n");
302 jffs2_inode_cachep
= kmem_cache_create("jffs2_i",
303 sizeof(struct jffs2_inode_info
),
304 0, SLAB_HWCACHE_ALIGN
|SLAB_RECLAIM_ACCOUNT
,
305 jffs2_i_init_once
, NULL
);
306 if (!jffs2_inode_cachep
) {
307 printk(KERN_ERR
"JFFS2 error: Failed to initialise inode cache\n");
310 ret
= jffs2_zlib_init();
312 printk(KERN_ERR
"JFFS2 error: Failed to initialise zlib workspaces\n");
315 ret
= jffs2_create_slab_caches();
317 printk(KERN_ERR
"JFFS2 error: Failed to initialise slab caches\n");
320 ret
= register_filesystem(&jffs2_fs_type
);
322 printk(KERN_ERR
"JFFS2 error: Failed to register filesystem\n");
328 jffs2_destroy_slab_caches();
335 static void __exit
exit_jffs2_fs(void)
337 unregister_filesystem(&jffs2_fs_type
);
338 jffs2_destroy_slab_caches();
340 kmem_cache_destroy(jffs2_inode_cachep
);
343 module_init(init_jffs2_fs
);
344 module_exit(exit_jffs2_fs
);
346 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
347 MODULE_AUTHOR("Red Hat, Inc.");
348 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
349 // the sake of this tag. It's Free Software.