jffs2: call jffs2_write_super from jffs2_sync_fs
[linux-2.6.git] / fs / jffs2 / super.c
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2001-2007 Red Hat, Inc.
5  *
6  * Created by David Woodhouse <dwmw2@infradead.org>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  */
11
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>
17 #include <linux/fs.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/super.h>
23 #include <linux/ctype.h>
24 #include <linux/namei.h>
25 #include <linux/exportfs.h>
26 #include "compr.h"
27 #include "nodelist.h"
28
29 static void jffs2_put_super(struct super_block *);
30
31 static struct kmem_cache *jffs2_inode_cachep;
32
33 static struct inode *jffs2_alloc_inode(struct super_block *sb)
34 {
35         struct jffs2_inode_info *f;
36
37         f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
38         if (!f)
39                 return NULL;
40         return &f->vfs_inode;
41 }
42
43 static void jffs2_destroy_inode(struct inode *inode)
44 {
45         kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
46 }
47
48 static void jffs2_i_init_once(void *foo)
49 {
50         struct jffs2_inode_info *f = foo;
51
52         mutex_init(&f->sem);
53         inode_init_once(&f->vfs_inode);
54 }
55
56 static void jffs2_write_super(struct super_block *sb)
57 {
58         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
59
60         lock_super(sb);
61         sb->s_dirt = 0;
62
63         if (!(sb->s_flags & MS_RDONLY)) {
64                 D1(printk(KERN_DEBUG "jffs2_write_super()\n"));
65                 jffs2_garbage_collect_trigger(c);
66                 jffs2_erase_pending_blocks(c, 0);
67                 jffs2_flush_wbuf_gc(c, 0);
68         }
69
70         unlock_super(sb);
71 }
72
73 static int jffs2_sync_fs(struct super_block *sb, int wait)
74 {
75         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
76
77         jffs2_write_super(sb);
78
79         mutex_lock(&c->alloc_sem);
80         jffs2_flush_wbuf_pad(c);
81         mutex_unlock(&c->alloc_sem);
82         return 0;
83 }
84
85 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
86                                          uint32_t generation)
87 {
88         /* We don't care about i_generation. We'll destroy the flash
89            before we start re-using inode numbers anyway. And even
90            if that wasn't true, we'd have other problems...*/
91         return jffs2_iget(sb, ino);
92 }
93
94 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
95                                          int fh_len, int fh_type)
96 {
97         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
98                                     jffs2_nfs_get_inode);
99 }
100
101 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
102                                          int fh_len, int fh_type)
103 {
104         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
105                                     jffs2_nfs_get_inode);
106 }
107
108 static struct dentry *jffs2_get_parent(struct dentry *child)
109 {
110         struct jffs2_inode_info *f;
111         uint32_t pino;
112
113         BUG_ON(!S_ISDIR(child->d_inode->i_mode));
114
115         f = JFFS2_INODE_INFO(child->d_inode);
116
117         pino = f->inocache->pino_nlink;
118
119         JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
120                     f->inocache->ino, pino);
121
122         return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
123 }
124
125 static struct export_operations jffs2_export_ops = {
126         .get_parent = jffs2_get_parent,
127         .fh_to_dentry = jffs2_fh_to_dentry,
128         .fh_to_parent = jffs2_fh_to_parent,
129 };
130
131 static const struct super_operations jffs2_super_operations =
132 {
133         .alloc_inode =  jffs2_alloc_inode,
134         .destroy_inode =jffs2_destroy_inode,
135         .put_super =    jffs2_put_super,
136         .write_super =  jffs2_write_super,
137         .statfs =       jffs2_statfs,
138         .remount_fs =   jffs2_remount_fs,
139         .clear_inode =  jffs2_clear_inode,
140         .dirty_inode =  jffs2_dirty_inode,
141         .sync_fs =      jffs2_sync_fs,
142 };
143
144 /*
145  * fill in the superblock
146  */
147 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
148 {
149         struct jffs2_sb_info *c;
150
151         D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
152                   " New superblock for device %d (\"%s\")\n",
153                   sb->s_mtd->index, sb->s_mtd->name));
154
155         c = kzalloc(sizeof(*c), GFP_KERNEL);
156         if (!c)
157                 return -ENOMEM;
158
159         c->mtd = sb->s_mtd;
160         c->os_priv = sb;
161         sb->s_fs_info = c;
162
163         /* Initialize JFFS2 superblock locks, the further initialization will
164          * be done later */
165         mutex_init(&c->alloc_sem);
166         mutex_init(&c->erase_free_sem);
167         init_waitqueue_head(&c->erase_wait);
168         init_waitqueue_head(&c->inocache_wq);
169         spin_lock_init(&c->erase_completion_lock);
170         spin_lock_init(&c->inocache_lock);
171
172         sb->s_op = &jffs2_super_operations;
173         sb->s_export_op = &jffs2_export_ops;
174         sb->s_flags = sb->s_flags | MS_NOATIME;
175         sb->s_xattr = jffs2_xattr_handlers;
176 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
177         sb->s_flags |= MS_POSIXACL;
178 #endif
179         return jffs2_do_fill_super(sb, data, silent);
180 }
181
182 static int jffs2_get_sb(struct file_system_type *fs_type,
183                         int flags, const char *dev_name,
184                         void *data, struct vfsmount *mnt)
185 {
186         return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
187                           mnt);
188 }
189
190 static void jffs2_put_super (struct super_block *sb)
191 {
192         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
193
194         D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
195
196         lock_kernel();
197
198         if (sb->s_dirt)
199                 jffs2_write_super(sb);
200
201         mutex_lock(&c->alloc_sem);
202         jffs2_flush_wbuf_pad(c);
203         mutex_unlock(&c->alloc_sem);
204
205         jffs2_sum_exit(c);
206
207         jffs2_free_ino_caches(c);
208         jffs2_free_raw_node_refs(c);
209         if (jffs2_blocks_use_vmalloc(c))
210                 vfree(c->blocks);
211         else
212                 kfree(c->blocks);
213         jffs2_flash_cleanup(c);
214         kfree(c->inocache_list);
215         jffs2_clear_xattr_subsystem(c);
216         if (c->mtd->sync)
217                 c->mtd->sync(c->mtd);
218
219         unlock_kernel();
220
221         D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
222 }
223
224 static void jffs2_kill_sb(struct super_block *sb)
225 {
226         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
227         if (!(sb->s_flags & MS_RDONLY))
228                 jffs2_stop_garbage_collect_thread(c);
229         kill_mtd_super(sb);
230         kfree(c);
231 }
232
233 static struct file_system_type jffs2_fs_type = {
234         .owner =        THIS_MODULE,
235         .name =         "jffs2",
236         .get_sb =       jffs2_get_sb,
237         .kill_sb =      jffs2_kill_sb,
238 };
239
240 static int __init init_jffs2_fs(void)
241 {
242         int ret;
243
244         /* Paranoia checks for on-medium structures. If we ask GCC
245            to pack them with __attribute__((packed)) then it _also_
246            assumes that they're not aligned -- so it emits crappy
247            code on some architectures. Ideally we want an attribute
248            which means just 'no padding', without the alignment
249            thing. But GCC doesn't have that -- we have to just
250            hope the structs are the right sizes, instead. */
251         BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
252         BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
253         BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
254         BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
255
256         printk(KERN_INFO "JFFS2 version 2.2."
257 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
258                " (NAND)"
259 #endif
260 #ifdef CONFIG_JFFS2_SUMMARY
261                " (SUMMARY) "
262 #endif
263                " © 2001-2006 Red Hat, Inc.\n");
264
265         jffs2_inode_cachep = kmem_cache_create("jffs2_i",
266                                              sizeof(struct jffs2_inode_info),
267                                              0, (SLAB_RECLAIM_ACCOUNT|
268                                                 SLAB_MEM_SPREAD),
269                                              jffs2_i_init_once);
270         if (!jffs2_inode_cachep) {
271                 printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
272                 return -ENOMEM;
273         }
274         ret = jffs2_compressors_init();
275         if (ret) {
276                 printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
277                 goto out;
278         }
279         ret = jffs2_create_slab_caches();
280         if (ret) {
281                 printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
282                 goto out_compressors;
283         }
284         ret = register_filesystem(&jffs2_fs_type);
285         if (ret) {
286                 printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
287                 goto out_slab;
288         }
289         return 0;
290
291  out_slab:
292         jffs2_destroy_slab_caches();
293  out_compressors:
294         jffs2_compressors_exit();
295  out:
296         kmem_cache_destroy(jffs2_inode_cachep);
297         return ret;
298 }
299
300 static void __exit exit_jffs2_fs(void)
301 {
302         unregister_filesystem(&jffs2_fs_type);
303         jffs2_destroy_slab_caches();
304         jffs2_compressors_exit();
305         kmem_cache_destroy(jffs2_inode_cachep);
306 }
307
308 module_init(init_jffs2_fs);
309 module_exit(exit_jffs2_fs);
310
311 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
312 MODULE_AUTHOR("Red Hat, Inc.");
313 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
314                        // the sake of this tag. It's Free Software.