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CommitLineData
1da177e4
LT
1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
c00c310e 4 * Copyright © 2001-2007 Red Hat, Inc.
1da177e4
LT
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
1da177e4
LT
10 */
11
5a528957
JP
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
1da177e4
LT
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/init.h>
18#include <linux/list.h>
19#include <linux/fs.h>
9c74034f 20#include <linux/err.h>
1da177e4 21#include <linux/mount.h>
92abc475 22#include <linux/parser.h>
1da177e4
LT
23#include <linux/jffs2.h>
24#include <linux/pagemap.h>
acaebfd8 25#include <linux/mtd/super.h>
1da177e4
LT
26#include <linux/ctype.h>
27#include <linux/namei.h>
92abc475 28#include <linux/seq_file.h>
5f556aab 29#include <linux/exportfs.h>
1da177e4
LT
30#include "compr.h"
31#include "nodelist.h"
32
33static void jffs2_put_super(struct super_block *);
34
e18b890b 35static struct kmem_cache *jffs2_inode_cachep;
1da177e4
LT
36
37static struct inode *jffs2_alloc_inode(struct super_block *sb)
38{
4e571aba
DW
39 struct jffs2_inode_info *f;
40
41 f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
42 if (!f)
1da177e4 43 return NULL;
4e571aba 44 return &f->vfs_inode;
1da177e4
LT
45}
46
fa0d7e3d 47static void jffs2_i_callback(struct rcu_head *head)
1da177e4 48{
fa0d7e3d 49 struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4
LT
50 kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
51}
52
fa0d7e3d
NP
53static void jffs2_destroy_inode(struct inode *inode)
54{
55 call_rcu(&inode->i_rcu, jffs2_i_callback);
56}
57
51cc5068 58static void jffs2_i_init_once(void *foo)
1da177e4 59{
4e571aba 60 struct jffs2_inode_info *f = foo;
1da177e4 61
4e571aba
DW
62 mutex_init(&f->sem);
63 inode_init_once(&f->vfs_inode);
1da177e4
LT
64}
65
92abc475
AS
66static const char *jffs2_compr_name(unsigned int compr)
67{
68 switch (compr) {
69 case JFFS2_COMPR_MODE_NONE:
70 return "none";
123005f3
AS
71#ifdef CONFIG_JFFS2_LZO
72 case JFFS2_COMPR_MODE_FORCELZO:
73 return "lzo";
74#endif
75#ifdef CONFIG_JFFS2_ZLIB
76 case JFFS2_COMPR_MODE_FORCEZLIB:
77 return "zlib";
78#endif
92abc475
AS
79 default:
80 /* should never happen; programmer error */
81 WARN_ON(1);
82 return "";
83 }
84}
85
34c80b1d 86static int jffs2_show_options(struct seq_file *s, struct dentry *root)
92abc475 87{
34c80b1d 88 struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb);
92abc475
AS
89 struct jffs2_mount_opts *opts = &c->mount_opts;
90
91 if (opts->override_compr)
92 seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
8da8ba2e
DD
93 if (opts->rp_size)
94 seq_printf(s, ",rp_size=%u", opts->rp_size / 1024);
92abc475
AS
95
96 return 0;
97}
98
1da177e4
LT
99static int jffs2_sync_fs(struct super_block *sb, int wait)
100{
101 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
102
a445f784
AB
103#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
104 cancel_delayed_work_sync(&c->wbuf_dwork);
105#endif
106
ced22070 107 mutex_lock(&c->alloc_sem);
1da177e4 108 jffs2_flush_wbuf_pad(c);
ced22070 109 mutex_unlock(&c->alloc_sem);
1da177e4
LT
110 return 0;
111}
112
5f556aab
DW
113static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
114 uint32_t generation)
115{
116 /* We don't care about i_generation. We'll destroy the flash
117 before we start re-using inode numbers anyway. And even
118 if that wasn't true, we'd have other problems...*/
119 return jffs2_iget(sb, ino);
120}
121
122static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
123 int fh_len, int fh_type)
124{
125 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
126 jffs2_nfs_get_inode);
127}
128
129static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
130 int fh_len, int fh_type)
131{
132 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
133 jffs2_nfs_get_inode);
134}
135
136static struct dentry *jffs2_get_parent(struct dentry *child)
137{
138 struct jffs2_inode_info *f;
139 uint32_t pino;
140
141 BUG_ON(!S_ISDIR(child->d_inode->i_mode));
142
143 f = JFFS2_INODE_INFO(child->d_inode);
144
145 pino = f->inocache->pino_nlink;
146
147 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
148 f->inocache->ino, pino);
149
150 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino));
151}
152
ac4cfdd6 153static const struct export_operations jffs2_export_ops = {
5f556aab
DW
154 .get_parent = jffs2_get_parent,
155 .fh_to_dentry = jffs2_fh_to_dentry,
156 .fh_to_parent = jffs2_fh_to_parent,
157};
158
92abc475
AS
159/*
160 * JFFS2 mount options.
161 *
162 * Opt_override_compr: override default compressor
8da8ba2e 163 * Opt_rp_size: size of reserved pool in KiB
92abc475
AS
164 * Opt_err: just end of array marker
165 */
166enum {
167 Opt_override_compr,
8da8ba2e 168 Opt_rp_size,
92abc475
AS
169 Opt_err,
170};
171
172static const match_table_t tokens = {
173 {Opt_override_compr, "compr=%s"},
8da8ba2e 174 {Opt_rp_size, "rp_size=%u"},
92abc475
AS
175 {Opt_err, NULL},
176};
177
178static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
179{
180 substring_t args[MAX_OPT_ARGS];
181 char *p, *name;
8da8ba2e 182 unsigned int opt;
92abc475
AS
183
184 if (!data)
185 return 0;
186
187 while ((p = strsep(&data, ","))) {
188 int token;
189
190 if (!*p)
191 continue;
192
193 token = match_token(p, tokens, args);
194 switch (token) {
195 case Opt_override_compr:
196 name = match_strdup(&args[0]);
197
198 if (!name)
199 return -ENOMEM;
123005f3 200 if (!strcmp(name, "none"))
92abc475 201 c->mount_opts.compr = JFFS2_COMPR_MODE_NONE;
123005f3
AS
202#ifdef CONFIG_JFFS2_LZO
203 else if (!strcmp(name, "lzo"))
204 c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO;
205#endif
206#ifdef CONFIG_JFFS2_ZLIB
207 else if (!strcmp(name, "zlib"))
208 c->mount_opts.compr =
209 JFFS2_COMPR_MODE_FORCEZLIB;
210#endif
211 else {
5a528957 212 pr_err("Error: unknown compressor \"%s\"\n",
da320f05 213 name);
123005f3
AS
214 kfree(name);
215 return -EINVAL;
92abc475
AS
216 }
217 kfree(name);
123005f3 218 c->mount_opts.override_compr = true;
92abc475 219 break;
8da8ba2e
DD
220 case Opt_rp_size:
221 if (match_int(&args[0], &opt))
222 return -EINVAL;
223 opt *= 1024;
224 if (opt > c->mtd->size) {
225 pr_warn("Too large reserve pool specified, max "
226 "is %llu KB\n", c->mtd->size / 1024);
227 return -EINVAL;
228 }
229 c->mount_opts.rp_size = opt;
230 break;
92abc475 231 default:
5a528957 232 pr_err("Error: unrecognized mount option '%s' or missing value\n",
da320f05 233 p);
92abc475
AS
234 return -EINVAL;
235 }
236 }
237
238 return 0;
239}
240
241static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
242{
243 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
244 int err;
245
246 err = jffs2_parse_options(c, data);
247 if (err)
248 return -EINVAL;
249
250 return jffs2_do_remount_fs(sb, flags, data);
251}
252
ee9b6d61 253static const struct super_operations jffs2_super_operations =
1da177e4
LT
254{
255 .alloc_inode = jffs2_alloc_inode,
256 .destroy_inode =jffs2_destroy_inode,
1da177e4 257 .put_super = jffs2_put_super,
1da177e4
LT
258 .statfs = jffs2_statfs,
259 .remount_fs = jffs2_remount_fs,
b57922d9 260 .evict_inode = jffs2_evict_inode,
1da177e4 261 .dirty_inode = jffs2_dirty_inode,
92abc475 262 .show_options = jffs2_show_options,
1da177e4
LT
263 .sync_fs = jffs2_sync_fs,
264};
265
acaebfd8
DH
266/*
267 * fill in the superblock
268 */
269static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
1da177e4 270{
1da177e4 271 struct jffs2_sb_info *c;
db719222
JB
272 int ret;
273
9c261b33 274 jffs2_dbg(1, "jffs2_get_sb_mtd():"
acaebfd8 275 " New superblock for device %d (\"%s\")\n",
9c261b33 276 sb->s_mtd->index, sb->s_mtd->name);
1da177e4 277
f8314dc6 278 c = kzalloc(sizeof(*c), GFP_KERNEL);
1a028dd2 279 if (!c)
454e2398 280 return -ENOMEM;
1da177e4 281
acaebfd8
DH
282 c->mtd = sb->s_mtd;
283 c->os_priv = sb;
284 sb->s_fs_info = c;
1da177e4 285
92abc475
AS
286 ret = jffs2_parse_options(c, data);
287 if (ret) {
288 kfree(c);
289 return -EINVAL;
290 }
291
acaebfd8
DH
292 /* Initialize JFFS2 superblock locks, the further initialization will
293 * be done later */
ced22070
DW
294 mutex_init(&c->alloc_sem);
295 mutex_init(&c->erase_free_sem);
b6220598
AB
296 init_waitqueue_head(&c->erase_wait);
297 init_waitqueue_head(&c->inocache_wq);
298 spin_lock_init(&c->erase_completion_lock);
299 spin_lock_init(&c->inocache_lock);
300
1da177e4 301 sb->s_op = &jffs2_super_operations;
5f556aab 302 sb->s_export_op = &jffs2_export_ops;
acaebfd8 303 sb->s_flags = sb->s_flags | MS_NOATIME;
aa98d7cf
KK
304 sb->s_xattr = jffs2_xattr_handlers;
305#ifdef CONFIG_JFFS2_FS_POSIX_ACL
306 sb->s_flags |= MS_POSIXACL;
307#endif
db719222 308 ret = jffs2_do_fill_super(sb, data, silent);
db719222 309 return ret;
1da177e4
LT
310}
311
848b83a5 312static struct dentry *jffs2_mount(struct file_system_type *fs_type,
454e2398 313 int flags, const char *dev_name,
848b83a5 314 void *data)
1da177e4 315{
848b83a5 316 return mount_mtd(fs_type, flags, dev_name, data, jffs2_fill_super);
1da177e4
LT
317}
318
319static void jffs2_put_super (struct super_block *sb)
320{
321 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
322
9c261b33 323 jffs2_dbg(2, "%s()\n", __func__);
1da177e4 324
ced22070 325 mutex_lock(&c->alloc_sem);
1da177e4 326 jffs2_flush_wbuf_pad(c);
ced22070 327 mutex_unlock(&c->alloc_sem);
e631ddba
FH
328
329 jffs2_sum_exit(c);
330
1da177e4
LT
331 jffs2_free_ino_caches(c);
332 jffs2_free_raw_node_refs(c);
4ce1f562 333 if (jffs2_blocks_use_vmalloc(c))
1da177e4
LT
334 vfree(c->blocks);
335 else
336 kfree(c->blocks);
337 jffs2_flash_cleanup(c);
338 kfree(c->inocache_list);
aa98d7cf 339 jffs2_clear_xattr_subsystem(c);
327cf292 340 mtd_sync(c->mtd);
9c261b33 341 jffs2_dbg(1, "%s(): returning\n", __func__);
1da177e4
LT
342}
343
344static void jffs2_kill_sb(struct super_block *sb)
345{
346 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
a69dde91
AB
347 if (!(sb->s_flags & MS_RDONLY))
348 jffs2_stop_garbage_collect_thread(c);
acaebfd8 349 kill_mtd_super(sb);
1da177e4
LT
350 kfree(c);
351}
352
353static struct file_system_type jffs2_fs_type = {
354 .owner = THIS_MODULE,
355 .name = "jffs2",
848b83a5 356 .mount = jffs2_mount,
1da177e4
LT
357 .kill_sb = jffs2_kill_sb,
358};
359
360static int __init init_jffs2_fs(void)
361{
362 int ret;
363
3e68fbb5
DW
364 /* Paranoia checks for on-medium structures. If we ask GCC
365 to pack them with __attribute__((packed)) then it _also_
366 assumes that they're not aligned -- so it emits crappy
367 code on some architectures. Ideally we want an attribute
368 which means just 'no padding', without the alignment
369 thing. But GCC doesn't have that -- we have to just
370 hope the structs are the right sizes, instead. */
2ecd05ae
AD
371 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
372 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
373 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
374 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
3e68fbb5 375
5a528957 376 pr_info("version 2.2."
2f82ce1e 377#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
1da177e4 378 " (NAND)"
e631ddba
FH
379#endif
380#ifdef CONFIG_JFFS2_SUMMARY
381 " (SUMMARY) "
1da177e4 382#endif
c00c310e 383 " © 2001-2006 Red Hat, Inc.\n");
1da177e4
LT
384
385 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
386 sizeof(struct jffs2_inode_info),
fffb60f9
PJ
387 0, (SLAB_RECLAIM_ACCOUNT|
388 SLAB_MEM_SPREAD),
20c2df83 389 jffs2_i_init_once);
1da177e4 390 if (!jffs2_inode_cachep) {
5a528957 391 pr_err("error: Failed to initialise inode cache\n");
1da177e4
LT
392 return -ENOMEM;
393 }
394 ret = jffs2_compressors_init();
395 if (ret) {
5a528957 396 pr_err("error: Failed to initialise compressors\n");
1da177e4
LT
397 goto out;
398 }
399 ret = jffs2_create_slab_caches();
400 if (ret) {
5a528957 401 pr_err("error: Failed to initialise slab caches\n");
1da177e4
LT
402 goto out_compressors;
403 }
404 ret = register_filesystem(&jffs2_fs_type);
405 if (ret) {
5a528957 406 pr_err("error: Failed to register filesystem\n");
1da177e4
LT
407 goto out_slab;
408 }
409 return 0;
410
411 out_slab:
412 jffs2_destroy_slab_caches();
413 out_compressors:
414 jffs2_compressors_exit();
415 out:
416 kmem_cache_destroy(jffs2_inode_cachep);
417 return ret;
418}
419
420static void __exit exit_jffs2_fs(void)
421{
422 unregister_filesystem(&jffs2_fs_type);
423 jffs2_destroy_slab_caches();
424 jffs2_compressors_exit();
8c0a8537
KS
425
426 /*
427 * Make sure all delayed rcu free inodes are flushed before we
428 * destroy cache.
429 */
430 rcu_barrier();
1da177e4
LT
431 kmem_cache_destroy(jffs2_inode_cachep);
432}
433
434module_init(init_jffs2_fs);
435module_exit(exit_jffs2_fs);
436
437MODULE_DESCRIPTION("The Journalling Flash File System, v2");
438MODULE_AUTHOR("Red Hat, Inc.");
182ec4ee 439MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
1da177e4 440 // the sake of this tag. It's Free Software.