Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / 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 "compr.h"
26 #include "nodelist.h"
27
28 static void jffs2_put_super(struct super_block *);
29
30 static struct kmem_cache *jffs2_inode_cachep;
31
32 static struct inode *jffs2_alloc_inode(struct super_block *sb)
33 {
34         struct jffs2_inode_info *ei;
35         ei = (struct jffs2_inode_info *)kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
36         if (!ei)
37                 return NULL;
38         return &ei->vfs_inode;
39 }
40
41 static void jffs2_destroy_inode(struct inode *inode)
42 {
43         kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
44 }
45
46 static void jffs2_i_init_once(struct kmem_cache *cachep, void *foo)
47 {
48         struct jffs2_inode_info *ei = (struct jffs2_inode_info *) foo;
49
50         init_MUTEX(&ei->sem);
51         inode_init_once(&ei->vfs_inode);
52 }
53
54 static int jffs2_sync_fs(struct super_block *sb, int wait)
55 {
56         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
57
58         down(&c->alloc_sem);
59         jffs2_flush_wbuf_pad(c);
60         up(&c->alloc_sem);
61         return 0;
62 }
63
64 static const struct super_operations jffs2_super_operations =
65 {
66         .alloc_inode =  jffs2_alloc_inode,
67         .destroy_inode =jffs2_destroy_inode,
68         .put_super =    jffs2_put_super,
69         .write_super =  jffs2_write_super,
70         .statfs =       jffs2_statfs,
71         .remount_fs =   jffs2_remount_fs,
72         .clear_inode =  jffs2_clear_inode,
73         .dirty_inode =  jffs2_dirty_inode,
74         .sync_fs =      jffs2_sync_fs,
75 };
76
77 /*
78  * fill in the superblock
79  */
80 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
81 {
82         struct jffs2_sb_info *c;
83
84         D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
85                   " New superblock for device %d (\"%s\")\n",
86                   sb->s_mtd->index, sb->s_mtd->name));
87
88         c = kzalloc(sizeof(*c), GFP_KERNEL);
89         if (!c)
90                 return -ENOMEM;
91
92         c->mtd = sb->s_mtd;
93         c->os_priv = sb;
94         sb->s_fs_info = c;
95
96         /* Initialize JFFS2 superblock locks, the further initialization will
97          * be done later */
98         init_MUTEX(&c->alloc_sem);
99         init_MUTEX(&c->erase_free_sem);
100         init_waitqueue_head(&c->erase_wait);
101         init_waitqueue_head(&c->inocache_wq);
102         spin_lock_init(&c->erase_completion_lock);
103         spin_lock_init(&c->inocache_lock);
104
105         sb->s_op = &jffs2_super_operations;
106         sb->s_flags = sb->s_flags | MS_NOATIME;
107         sb->s_xattr = jffs2_xattr_handlers;
108 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
109         sb->s_flags |= MS_POSIXACL;
110 #endif
111         return jffs2_do_fill_super(sb, data, silent);
112 }
113
114 static int jffs2_get_sb(struct file_system_type *fs_type,
115                         int flags, const char *dev_name,
116                         void *data, struct vfsmount *mnt)
117 {
118         return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
119                           mnt);
120 }
121
122 static void jffs2_put_super (struct super_block *sb)
123 {
124         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
125
126         D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
127
128         down(&c->alloc_sem);
129         jffs2_flush_wbuf_pad(c);
130         up(&c->alloc_sem);
131
132         jffs2_sum_exit(c);
133
134         jffs2_free_ino_caches(c);
135         jffs2_free_raw_node_refs(c);
136         if (jffs2_blocks_use_vmalloc(c))
137                 vfree(c->blocks);
138         else
139                 kfree(c->blocks);
140         jffs2_flash_cleanup(c);
141         kfree(c->inocache_list);
142         jffs2_clear_xattr_subsystem(c);
143         if (c->mtd->sync)
144                 c->mtd->sync(c->mtd);
145
146         D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
147 }
148
149 static void jffs2_kill_sb(struct super_block *sb)
150 {
151         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
152         if (!(sb->s_flags & MS_RDONLY))
153                 jffs2_stop_garbage_collect_thread(c);
154         kill_mtd_super(sb);
155         kfree(c);
156 }
157
158 static struct file_system_type jffs2_fs_type = {
159         .owner =        THIS_MODULE,
160         .name =         "jffs2",
161         .get_sb =       jffs2_get_sb,
162         .kill_sb =      jffs2_kill_sb,
163 };
164
165 static int __init init_jffs2_fs(void)
166 {
167         int ret;
168
169         /* Paranoia checks for on-medium structures. If we ask GCC
170            to pack them with __attribute__((packed)) then it _also_
171            assumes that they're not aligned -- so it emits crappy
172            code on some architectures. Ideally we want an attribute
173            which means just 'no padding', without the alignment
174            thing. But GCC doesn't have that -- we have to just
175            hope the structs are the right sizes, instead. */
176         BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
177         BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
178         BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
179         BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
180
181         printk(KERN_INFO "JFFS2 version 2.2."
182 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
183                " (NAND)"
184 #endif
185 #ifdef CONFIG_JFFS2_SUMMARY
186                " (SUMMARY) "
187 #endif
188                " © 2001-2006 Red Hat, Inc.\n");
189
190         jffs2_inode_cachep = kmem_cache_create("jffs2_i",
191                                              sizeof(struct jffs2_inode_info),
192                                              0, (SLAB_RECLAIM_ACCOUNT|
193                                                 SLAB_MEM_SPREAD),
194                                              jffs2_i_init_once);
195         if (!jffs2_inode_cachep) {
196                 printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
197                 return -ENOMEM;
198         }
199         ret = jffs2_compressors_init();
200         if (ret) {
201                 printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
202                 goto out;
203         }
204         ret = jffs2_create_slab_caches();
205         if (ret) {
206                 printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
207                 goto out_compressors;
208         }
209         ret = register_filesystem(&jffs2_fs_type);
210         if (ret) {
211                 printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
212                 goto out_slab;
213         }
214         return 0;
215
216  out_slab:
217         jffs2_destroy_slab_caches();
218  out_compressors:
219         jffs2_compressors_exit();
220  out:
221         kmem_cache_destroy(jffs2_inode_cachep);
222         return ret;
223 }
224
225 static void __exit exit_jffs2_fs(void)
226 {
227         unregister_filesystem(&jffs2_fs_type);
228         jffs2_destroy_slab_caches();
229         jffs2_compressors_exit();
230         kmem_cache_destroy(jffs2_inode_cachep);
231 }
232
233 module_init(init_jffs2_fs);
234 module_exit(exit_jffs2_fs);
235
236 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
237 MODULE_AUTHOR("Red Hat, Inc.");
238 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
239                        // the sake of this tag. It's Free Software.