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/smp_lock.h>
16 #include <linux/init.h>
17 #include <linux/list.h>
18 #include <linux/fs.h>
19 #include <linux/err.h>
20 #include <linux/mount.h>
21 #include <linux/jffs2.h>
22 #include <linux/pagemap.h>
23 #include <linux/mtd/super.h>
24 #include <linux/ctype.h>
25 #include <linux/namei.h>
26 #include <linux/exportfs.h>
27 #include "compr.h"
28 #include "nodelist.h"
29
30 static void jffs2_put_super(struct super_block *);
31
32 static struct kmem_cache *jffs2_inode_cachep;
33
34 static struct inode *jffs2_alloc_inode(struct super_block *sb)
35 {
36 struct jffs2_inode_info *f;
37
38 f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
39 if (!f)
40 return NULL;
41 return &f->vfs_inode;
42 }
43
44 static void jffs2_destroy_inode(struct inode *inode)
45 {
46 kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
47 }
48
49 static void jffs2_i_init_once(void *foo)
50 {
51 struct jffs2_inode_info *f = foo;
52
53 mutex_init(&f->sem);
54 inode_init_once(&f->vfs_inode);
55 }
56
57 static void jffs2_write_super(struct super_block *sb)
58 {
59 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
60
61 lock_super(sb);
62 sb->s_dirt = 0;
63
64 if (!(sb->s_flags & MS_RDONLY)) {
65 D1(printk(KERN_DEBUG "jffs2_write_super()\n"));
66 jffs2_garbage_collect_trigger(c);
67 jffs2_erase_pending_blocks(c, 0);
68 jffs2_flush_wbuf_gc(c, 0);
69 }
70
71 unlock_super(sb);
72 }
73
74 static int jffs2_sync_fs(struct super_block *sb, int wait)
75 {
76 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
77
78 jffs2_write_super(sb);
79
80 mutex_lock(&c->alloc_sem);
81 jffs2_flush_wbuf_pad(c);
82 mutex_unlock(&c->alloc_sem);
83 return 0;
84 }
85
86 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
87 uint32_t generation)
88 {
89 /* We don't care about i_generation. We'll destroy the flash
90 before we start re-using inode numbers anyway. And even
91 if that wasn't true, we'd have other problems...*/
92 return jffs2_iget(sb, ino);
93 }
94
95 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
96 int fh_len, int fh_type)
97 {
98 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
99 jffs2_nfs_get_inode);
100 }
101
102 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
103 int fh_len, int fh_type)
104 {
105 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
106 jffs2_nfs_get_inode);
107 }
108
109 static struct dentry *jffs2_get_parent(struct dentry *child)
110 {
111 struct jffs2_inode_info *f;
112 uint32_t pino;
113
114 BUG_ON(!S_ISDIR(child->d_inode->i_mode));
115
116 f = JFFS2_INODE_INFO(child->d_inode);
117
118 pino = f->inocache->pino_nlink;
119
120 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
121 f->inocache->ino, pino);
122
123 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
124 }
125
126 static struct export_operations jffs2_export_ops = {
127 .get_parent = jffs2_get_parent,
128 .fh_to_dentry = jffs2_fh_to_dentry,
129 .fh_to_parent = jffs2_fh_to_parent,
130 };
131
132 static const struct super_operations jffs2_super_operations =
133 {
134 .alloc_inode = jffs2_alloc_inode,
135 .destroy_inode =jffs2_destroy_inode,
136 .put_super = jffs2_put_super,
137 .write_super = jffs2_write_super,
138 .statfs = jffs2_statfs,
139 .remount_fs = jffs2_remount_fs,
140 .clear_inode = jffs2_clear_inode,
141 .dirty_inode = jffs2_dirty_inode,
142 .sync_fs = jffs2_sync_fs,
143 };
144
145 /*
146 * fill in the superblock
147 */
148 static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
149 {
150 struct jffs2_sb_info *c;
151
152 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
153 " New superblock for device %d (\"%s\")\n",
154 sb->s_mtd->index, sb->s_mtd->name));
155
156 c = kzalloc(sizeof(*c), GFP_KERNEL);
157 if (!c)
158 return -ENOMEM;
159
160 c->mtd = sb->s_mtd;
161 c->os_priv = sb;
162 sb->s_fs_info = c;
163
164 /* Initialize JFFS2 superblock locks, the further initialization will
165 * be done later */
166 mutex_init(&c->alloc_sem);
167 mutex_init(&c->erase_free_sem);
168 init_waitqueue_head(&c->erase_wait);
169 init_waitqueue_head(&c->inocache_wq);
170 spin_lock_init(&c->erase_completion_lock);
171 spin_lock_init(&c->inocache_lock);
172
173 sb->s_op = &jffs2_super_operations;
174 sb->s_export_op = &jffs2_export_ops;
175 sb->s_flags = sb->s_flags | MS_NOATIME;
176 sb->s_xattr = jffs2_xattr_handlers;
177 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
178 sb->s_flags |= MS_POSIXACL;
179 #endif
180 return jffs2_do_fill_super(sb, data, silent);
181 }
182
183 static int jffs2_get_sb(struct file_system_type *fs_type,
184 int flags, const char *dev_name,
185 void *data, struct vfsmount *mnt)
186 {
187 return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
188 mnt);
189 }
190
191 static void jffs2_put_super (struct super_block *sb)
192 {
193 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
194
195 D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
196
197 lock_kernel();
198
199 if (sb->s_dirt)
200 jffs2_write_super(sb);
201
202 mutex_lock(&c->alloc_sem);
203 jffs2_flush_wbuf_pad(c);
204 mutex_unlock(&c->alloc_sem);
205
206 jffs2_sum_exit(c);
207
208 jffs2_free_ino_caches(c);
209 jffs2_free_raw_node_refs(c);
210 if (jffs2_blocks_use_vmalloc(c))
211 vfree(c->blocks);
212 else
213 kfree(c->blocks);
214 jffs2_flash_cleanup(c);
215 kfree(c->inocache_list);
216 jffs2_clear_xattr_subsystem(c);
217 if (c->mtd->sync)
218 c->mtd->sync(c->mtd);
219
220 unlock_kernel();
221
222 D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
223 }
224
225 static void jffs2_kill_sb(struct super_block *sb)
226 {
227 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
228 if (!(sb->s_flags & MS_RDONLY))
229 jffs2_stop_garbage_collect_thread(c);
230 kill_mtd_super(sb);
231 kfree(c);
232 }
233
234 static struct file_system_type jffs2_fs_type = {
235 .owner = THIS_MODULE,
236 .name = "jffs2",
237 .get_sb = jffs2_get_sb,
238 .kill_sb = jffs2_kill_sb,
239 };
240
241 static int __init init_jffs2_fs(void)
242 {
243 int ret;
244
245 /* Paranoia checks for on-medium structures. If we ask GCC
246 to pack them with __attribute__((packed)) then it _also_
247 assumes that they're not aligned -- so it emits crappy
248 code on some architectures. Ideally we want an attribute
249 which means just 'no padding', without the alignment
250 thing. But GCC doesn't have that -- we have to just
251 hope the structs are the right sizes, instead. */
252 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
253 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
254 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
255 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
256
257 printk(KERN_INFO "JFFS2 version 2.2."
258 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
259 " (NAND)"
260 #endif
261 #ifdef CONFIG_JFFS2_SUMMARY
262 " (SUMMARY) "
263 #endif
264 " © 2001-2006 Red Hat, Inc.\n");
265
266 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
267 sizeof(struct jffs2_inode_info),
268 0, (SLAB_RECLAIM_ACCOUNT|
269 SLAB_MEM_SPREAD),
270 jffs2_i_init_once);
271 if (!jffs2_inode_cachep) {
272 printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
273 return -ENOMEM;
274 }
275 ret = jffs2_compressors_init();
276 if (ret) {
277 printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
278 goto out;
279 }
280 ret = jffs2_create_slab_caches();
281 if (ret) {
282 printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
283 goto out_compressors;
284 }
285 ret = register_filesystem(&jffs2_fs_type);
286 if (ret) {
287 printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
288 goto out_slab;
289 }
290 return 0;
291
292 out_slab:
293 jffs2_destroy_slab_caches();
294 out_compressors:
295 jffs2_compressors_exit();
296 out:
297 kmem_cache_destroy(jffs2_inode_cachep);
298 return ret;
299 }
300
301 static void __exit exit_jffs2_fs(void)
302 {
303 unregister_filesystem(&jffs2_fs_type);
304 jffs2_destroy_slab_caches();
305 jffs2_compressors_exit();
306 kmem_cache_destroy(jffs2_inode_cachep);
307 }
308
309 module_init(init_jffs2_fs);
310 module_exit(exit_jffs2_fs);
311
312 MODULE_DESCRIPTION("The Journalling Flash File System, v2");
313 MODULE_AUTHOR("Red Hat, Inc.");
314 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
315 // the sake of this tag. It's Free Software.
316
|
This page was automatically generated by the
LXR engine.
|