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 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/list.h>
18 #include <linux/err.h>
19 #include <linux/mount.h>
20 #include <linux/jffs2.h>
21 #include <linux/pagemap.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/ctype.h>
24 #include <linux/namei.h>
28 static void jffs2_put_super(struct super_block
*);
30 static struct kmem_cache
*jffs2_inode_cachep
;
32 static struct inode
*jffs2_alloc_inode(struct super_block
*sb
)
34 struct jffs2_inode_info
*ei
;
35 ei
= (struct jffs2_inode_info
*)kmem_cache_alloc(jffs2_inode_cachep
, GFP_KERNEL
);
38 return &ei
->vfs_inode
;
41 static void jffs2_destroy_inode(struct inode
*inode
)
43 kmem_cache_free(jffs2_inode_cachep
, JFFS2_INODE_INFO(inode
));
46 static void jffs2_i_init_once(void * foo
, struct kmem_cache
* cachep
, unsigned long flags
)
48 struct jffs2_inode_info
*ei
= (struct jffs2_inode_info
*) foo
;
50 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
51 SLAB_CTOR_CONSTRUCTOR
) {
53 inode_init_once(&ei
->vfs_inode
);
57 static int jffs2_sync_fs(struct super_block
*sb
, int wait
)
59 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
62 jffs2_flush_wbuf_pad(c
);
67 static const struct super_operations jffs2_super_operations
=
69 .alloc_inode
= jffs2_alloc_inode
,
70 .destroy_inode
=jffs2_destroy_inode
,
71 .read_inode
= jffs2_read_inode
,
72 .put_super
= jffs2_put_super
,
73 .write_super
= jffs2_write_super
,
74 .statfs
= jffs2_statfs
,
75 .remount_fs
= jffs2_remount_fs
,
76 .clear_inode
= jffs2_clear_inode
,
77 .dirty_inode
= jffs2_dirty_inode
,
78 .sync_fs
= jffs2_sync_fs
,
81 static int jffs2_sb_compare(struct super_block
*sb
, void *data
)
83 struct jffs2_sb_info
*p
= data
;
84 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
86 /* The superblocks are considered to be equivalent if the underlying MTD
87 device is the same one */
88 if (c
->mtd
== p
->mtd
) {
89 D1(printk(KERN_DEBUG
"jffs2_sb_compare: match on device %d (\"%s\")\n", p
->mtd
->index
, p
->mtd
->name
));
92 D1(printk(KERN_DEBUG
"jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n",
93 c
->mtd
->index
, c
->mtd
->name
, p
->mtd
->index
, p
->mtd
->name
));
98 static int jffs2_sb_set(struct super_block
*sb
, void *data
)
100 struct jffs2_sb_info
*p
= data
;
102 /* For persistence of NFS exports etc. we use the same s_dev
103 each time we mount the device, don't just use an anonymous
107 sb
->s_dev
= MKDEV(MTD_BLOCK_MAJOR
, p
->mtd
->index
);
112 static int jffs2_get_sb_mtd(struct file_system_type
*fs_type
,
113 int flags
, const char *dev_name
,
114 void *data
, struct mtd_info
*mtd
,
115 struct vfsmount
*mnt
)
117 struct super_block
*sb
;
118 struct jffs2_sb_info
*c
;
121 c
= kzalloc(sizeof(*c
), GFP_KERNEL
);
126 sb
= sget(fs_type
, jffs2_sb_compare
, jffs2_sb_set
, c
);
132 /* New mountpoint for JFFS2 which is already mounted */
133 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n",
134 mtd
->index
, mtd
->name
));
135 ret
= simple_set_mnt(mnt
, sb
);
139 D1(printk(KERN_DEBUG
"jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n",
140 mtd
->index
, mtd
->name
));
142 /* Initialize JFFS2 superblock locks, the further initialization will be
144 init_MUTEX(&c
->alloc_sem
);
145 init_MUTEX(&c
->erase_free_sem
);
146 init_waitqueue_head(&c
->erase_wait
);
147 init_waitqueue_head(&c
->inocache_wq
);
148 spin_lock_init(&c
->erase_completion_lock
);
149 spin_lock_init(&c
->inocache_lock
);
151 sb
->s_op
= &jffs2_super_operations
;
152 sb
->s_flags
= flags
| MS_NOATIME
;
153 sb
->s_xattr
= jffs2_xattr_handlers
;
154 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
155 sb
->s_flags
|= MS_POSIXACL
;
157 ret
= jffs2_do_fill_super(sb
, data
, flags
& MS_SILENT
? 1 : 0);
160 /* Failure case... */
161 up_write(&sb
->s_umount
);
162 deactivate_super(sb
);
166 sb
->s_flags
|= MS_ACTIVE
;
167 return simple_set_mnt(mnt
, sb
);
178 static int jffs2_get_sb_mtdnr(struct file_system_type
*fs_type
,
179 int flags
, const char *dev_name
,
180 void *data
, int mtdnr
,
181 struct vfsmount
*mnt
)
183 struct mtd_info
*mtd
;
185 mtd
= get_mtd_device(NULL
, mtdnr
);
187 D1(printk(KERN_DEBUG
"jffs2: MTD device #%u doesn't appear to exist\n", mtdnr
));
191 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
, mnt
);
194 static int jffs2_get_sb(struct file_system_type
*fs_type
,
195 int flags
, const char *dev_name
,
196 void *data
, struct vfsmount
*mnt
)
205 D1(printk(KERN_DEBUG
"jffs2_get_sb(): dev_name \"%s\"\n", dev_name
));
207 /* The preferred way of mounting in future; especially when
208 CONFIG_BLK_DEV is implemented - we specify the underlying
209 MTD device by number or by name, so that we don't require
210 block device support to be present in the kernel. */
212 /* FIXME: How to do the root fs this way? */
214 if (dev_name
[0] == 'm' && dev_name
[1] == 't' && dev_name
[2] == 'd') {
215 /* Probably mounting without the blkdev crap */
216 if (dev_name
[3] == ':') {
217 struct mtd_info
*mtd
;
219 /* Mount by MTD device name */
220 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name
+4));
221 for (mtdnr
= 0; mtdnr
< MAX_MTD_DEVICES
; mtdnr
++) {
222 mtd
= get_mtd_device(NULL
, mtdnr
);
224 if (!strcmp(mtd
->name
, dev_name
+4))
225 return jffs2_get_sb_mtd(fs_type
, flags
, dev_name
, data
, mtd
, mnt
);
229 printk(KERN_NOTICE
"jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name
+4);
230 } else if (isdigit(dev_name
[3])) {
231 /* Mount by MTD device number name */
234 mtdnr
= simple_strtoul(dev_name
+3, &endptr
, 0);
236 /* It was a valid number */
237 D1(printk(KERN_DEBUG
"jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr
));
238 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
, mnt
);
243 /* Try the old way - the hack where we allowed users to mount
244 /dev/mtdblock$(n) but didn't actually _use_ the blkdev */
246 err
= path_lookup(dev_name
, LOOKUP_FOLLOW
, &nd
);
248 D1(printk(KERN_DEBUG
"jffs2_get_sb(): path_lookup() returned %d, inode %p\n",
249 err
, nd
.dentry
->d_inode
));
256 if (!S_ISBLK(nd
.dentry
->d_inode
->i_mode
))
259 if (nd
.mnt
->mnt_flags
& MNT_NODEV
) {
264 if (imajor(nd
.dentry
->d_inode
) != MTD_BLOCK_MAJOR
) {
265 if (!(flags
& MS_SILENT
))
266 printk(KERN_NOTICE
"Attempt to mount non-MTD device \"%s\" as JFFS2\n",
271 mtdnr
= iminor(nd
.dentry
->d_inode
);
274 return jffs2_get_sb_mtdnr(fs_type
, flags
, dev_name
, data
, mtdnr
, mnt
);
281 static void jffs2_put_super (struct super_block
*sb
)
283 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
285 D2(printk(KERN_DEBUG
"jffs2: jffs2_put_super()\n"));
288 jffs2_flush_wbuf_pad(c
);
293 jffs2_free_ino_caches(c
);
294 jffs2_free_raw_node_refs(c
);
295 if (jffs2_blocks_use_vmalloc(c
))
299 jffs2_flash_cleanup(c
);
300 kfree(c
->inocache_list
);
301 jffs2_clear_xattr_subsystem(c
);
303 c
->mtd
->sync(c
->mtd
);
305 D1(printk(KERN_DEBUG
"jffs2_put_super returning\n"));
308 static void jffs2_kill_sb(struct super_block
*sb
)
310 struct jffs2_sb_info
*c
= JFFS2_SB_INFO(sb
);
311 if (!(sb
->s_flags
& MS_RDONLY
))
312 jffs2_stop_garbage_collect_thread(c
);
313 generic_shutdown_super(sb
);
314 put_mtd_device(c
->mtd
);
318 static struct file_system_type jffs2_fs_type
= {
319 .owner
= THIS_MODULE
,
321 .get_sb
= jffs2_get_sb
,
322 .kill_sb
= jffs2_kill_sb
,
325 static int __init
init_jffs2_fs(void)
329 /* Paranoia checks for on-medium structures. If we ask GCC
330 to pack them with __attribute__((packed)) then it _also_
331 assumes that they're not aligned -- so it emits crappy
332 code on some architectures. Ideally we want an attribute
333 which means just 'no padding', without the alignment
334 thing. But GCC doesn't have that -- we have to just
335 hope the structs are the right sizes, instead. */
336 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node
) != 12);
337 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent
) != 40);
338 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode
) != 68);
339 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary
) != 32);
341 printk(KERN_INFO
"JFFS2 version 2.2."
342 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
345 #ifdef CONFIG_JFFS2_SUMMARY
348 " © 2001-2006 Red Hat, Inc.\n");
350 jffs2_inode_cachep
= kmem_cache_create("jffs2_i",
351 sizeof(struct jffs2_inode_info
),
352 0, (SLAB_RECLAIM_ACCOUNT
|
354 jffs2_i_init_once
, NULL
);
355 if (!jffs2_inode_cachep
) {
356 printk(KERN_ERR
"JFFS2 error: Failed to initialise inode cache\n");
359 ret
= jffs2_compressors_init();
361 printk(KERN_ERR
"JFFS2 error: Failed to initialise compressors\n");
364 ret
= jffs2_create_slab_caches();
366 printk(KERN_ERR
"JFFS2 error: Failed to initialise slab caches\n");
367 goto out_compressors
;
369 ret
= register_filesystem(&jffs2_fs_type
);
371 printk(KERN_ERR
"JFFS2 error: Failed to register filesystem\n");
377 jffs2_destroy_slab_caches();
379 jffs2_compressors_exit();
381 kmem_cache_destroy(jffs2_inode_cachep
);
385 static void __exit
exit_jffs2_fs(void)
387 unregister_filesystem(&jffs2_fs_type
);
388 jffs2_destroy_slab_caches();
389 jffs2_compressors_exit();
390 kmem_cache_destroy(jffs2_inode_cachep
);
393 module_init(init_jffs2_fs
);
394 module_exit(exit_jffs2_fs
);
396 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
397 MODULE_AUTHOR("Red Hat, Inc.");
398 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
399 // the sake of this tag. It's Free Software.