Merge tag 'nfs-for-5.1-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
[linux-2.6-block.git] / fs / jffs2 / super.c
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 103#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
a788c527
DS
104 if (jffs2_is_writebuffered(c))
105 cancel_delayed_work_sync(&c->wbuf_dwork);
a445f784
AB
106#endif
107
ced22070 108 mutex_lock(&c->alloc_sem);
1da177e4 109 jffs2_flush_wbuf_pad(c);
ced22070 110 mutex_unlock(&c->alloc_sem);
1da177e4
LT
111 return 0;
112}
113
5f556aab
DW
114static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
115 uint32_t generation)
116{
117 /* We don't care about i_generation. We'll destroy the flash
118 before we start re-using inode numbers anyway. And even
119 if that wasn't true, we'd have other problems...*/
120 return jffs2_iget(sb, ino);
121}
122
123static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
124 int fh_len, int fh_type)
125{
126 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
127 jffs2_nfs_get_inode);
128}
129
130static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
131 int fh_len, int fh_type)
132{
133 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
134 jffs2_nfs_get_inode);
135}
136
137static struct dentry *jffs2_get_parent(struct dentry *child)
138{
139 struct jffs2_inode_info *f;
140 uint32_t pino;
141
e36cb0b8 142 BUG_ON(!d_is_dir(child));
5f556aab 143
2b0143b5 144 f = JFFS2_INODE_INFO(d_inode(child));
5f556aab
DW
145
146 pino = f->inocache->pino_nlink;
147
148 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
149 f->inocache->ino, pino);
150
fc64005c 151 return d_obtain_alias(jffs2_iget(child->d_sb, pino));
5f556aab
DW
152}
153
ac4cfdd6 154static const struct export_operations jffs2_export_ops = {
5f556aab
DW
155 .get_parent = jffs2_get_parent,
156 .fh_to_dentry = jffs2_fh_to_dentry,
157 .fh_to_parent = jffs2_fh_to_parent,
158};
159
92abc475
AS
160/*
161 * JFFS2 mount options.
162 *
163 * Opt_override_compr: override default compressor
8da8ba2e 164 * Opt_rp_size: size of reserved pool in KiB
92abc475
AS
165 * Opt_err: just end of array marker
166 */
167enum {
168 Opt_override_compr,
8da8ba2e 169 Opt_rp_size,
92abc475
AS
170 Opt_err,
171};
172
173static const match_table_t tokens = {
174 {Opt_override_compr, "compr=%s"},
8da8ba2e 175 {Opt_rp_size, "rp_size=%u"},
92abc475
AS
176 {Opt_err, NULL},
177};
178
179static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
180{
181 substring_t args[MAX_OPT_ARGS];
182 char *p, *name;
8da8ba2e 183 unsigned int opt;
92abc475
AS
184
185 if (!data)
186 return 0;
187
188 while ((p = strsep(&data, ","))) {
189 int token;
190
191 if (!*p)
192 continue;
193
194 token = match_token(p, tokens, args);
195 switch (token) {
196 case Opt_override_compr:
197 name = match_strdup(&args[0]);
198
199 if (!name)
200 return -ENOMEM;
123005f3 201 if (!strcmp(name, "none"))
92abc475 202 c->mount_opts.compr = JFFS2_COMPR_MODE_NONE;
123005f3
AS
203#ifdef CONFIG_JFFS2_LZO
204 else if (!strcmp(name, "lzo"))
205 c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO;
206#endif
207#ifdef CONFIG_JFFS2_ZLIB
208 else if (!strcmp(name, "zlib"))
209 c->mount_opts.compr =
210 JFFS2_COMPR_MODE_FORCEZLIB;
211#endif
212 else {
5a528957 213 pr_err("Error: unknown compressor \"%s\"\n",
da320f05 214 name);
123005f3
AS
215 kfree(name);
216 return -EINVAL;
92abc475
AS
217 }
218 kfree(name);
123005f3 219 c->mount_opts.override_compr = true;
92abc475 220 break;
8da8ba2e
DD
221 case Opt_rp_size:
222 if (match_int(&args[0], &opt))
223 return -EINVAL;
224 opt *= 1024;
225 if (opt > c->mtd->size) {
226 pr_warn("Too large reserve pool specified, max "
227 "is %llu KB\n", c->mtd->size / 1024);
228 return -EINVAL;
229 }
230 c->mount_opts.rp_size = opt;
231 break;
92abc475 232 default:
5a528957 233 pr_err("Error: unrecognized mount option '%s' or missing value\n",
da320f05 234 p);
92abc475
AS
235 return -EINVAL;
236 }
237 }
238
239 return 0;
240}
241
242static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
243{
244 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
245 int err;
246
02b9984d 247 sync_filesystem(sb);
92abc475
AS
248 err = jffs2_parse_options(c, data);
249 if (err)
250 return -EINVAL;
251
252 return jffs2_do_remount_fs(sb, flags, data);
253}
254
ee9b6d61 255static const struct super_operations jffs2_super_operations =
1da177e4
LT
256{
257 .alloc_inode = jffs2_alloc_inode,
258 .destroy_inode =jffs2_destroy_inode,
1da177e4 259 .put_super = jffs2_put_super,
1da177e4
LT
260 .statfs = jffs2_statfs,
261 .remount_fs = jffs2_remount_fs,
b57922d9 262 .evict_inode = jffs2_evict_inode,
1da177e4 263 .dirty_inode = jffs2_dirty_inode,
92abc475 264 .show_options = jffs2_show_options,
1da177e4
LT
265 .sync_fs = jffs2_sync_fs,
266};
267
acaebfd8
DH
268/*
269 * fill in the superblock
270 */
271static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
1da177e4 272{
1da177e4 273 struct jffs2_sb_info *c;
db719222
JB
274 int ret;
275
9c261b33 276 jffs2_dbg(1, "jffs2_get_sb_mtd():"
acaebfd8 277 " New superblock for device %d (\"%s\")\n",
9c261b33 278 sb->s_mtd->index, sb->s_mtd->name);
1da177e4 279
f8314dc6 280 c = kzalloc(sizeof(*c), GFP_KERNEL);
1a028dd2 281 if (!c)
454e2398 282 return -ENOMEM;
1da177e4 283
acaebfd8
DH
284 c->mtd = sb->s_mtd;
285 c->os_priv = sb;
286 sb->s_fs_info = c;
1da177e4 287
92abc475 288 ret = jffs2_parse_options(c, data);
92e2921f 289 if (ret)
92abc475 290 return -EINVAL;
92abc475 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;
1751e8a6 303 sb->s_flags = sb->s_flags | SB_NOATIME;
aa98d7cf
KK
304 sb->s_xattr = jffs2_xattr_handlers;
305#ifdef CONFIG_JFFS2_FS_POSIX_ACL
1751e8a6 306 sb->s_flags |= SB_POSIXACL;
aa98d7cf 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);
1d5cfdb0 333 kvfree(c->blocks);
1da177e4
LT
334 jffs2_flash_cleanup(c);
335 kfree(c->inocache_list);
aa98d7cf 336 jffs2_clear_xattr_subsystem(c);
327cf292 337 mtd_sync(c->mtd);
9c261b33 338 jffs2_dbg(1, "%s(): returning\n", __func__);
1da177e4
LT
339}
340
341static void jffs2_kill_sb(struct super_block *sb)
342{
343 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
c66b23c2 344 if (c && !sb_rdonly(sb))
a69dde91 345 jffs2_stop_garbage_collect_thread(c);
acaebfd8 346 kill_mtd_super(sb);
1da177e4
LT
347 kfree(c);
348}
349
350static struct file_system_type jffs2_fs_type = {
351 .owner = THIS_MODULE,
352 .name = "jffs2",
848b83a5 353 .mount = jffs2_mount,
1da177e4
LT
354 .kill_sb = jffs2_kill_sb,
355};
7f78e035 356MODULE_ALIAS_FS("jffs2");
1da177e4
LT
357
358static int __init init_jffs2_fs(void)
359{
360 int ret;
361
3e68fbb5
DW
362 /* Paranoia checks for on-medium structures. If we ask GCC
363 to pack them with __attribute__((packed)) then it _also_
364 assumes that they're not aligned -- so it emits crappy
365 code on some architectures. Ideally we want an attribute
366 which means just 'no padding', without the alignment
367 thing. But GCC doesn't have that -- we have to just
368 hope the structs are the right sizes, instead. */
2ecd05ae
AD
369 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
370 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
371 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
372 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
3e68fbb5 373
5a528957 374 pr_info("version 2.2."
2f82ce1e 375#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
1da177e4 376 " (NAND)"
e631ddba
FH
377#endif
378#ifdef CONFIG_JFFS2_SUMMARY
379 " (SUMMARY) "
1da177e4 380#endif
c00c310e 381 " © 2001-2006 Red Hat, Inc.\n");
1da177e4
LT
382
383 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
384 sizeof(struct jffs2_inode_info),
fffb60f9 385 0, (SLAB_RECLAIM_ACCOUNT|
5d097056 386 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
20c2df83 387 jffs2_i_init_once);
1da177e4 388 if (!jffs2_inode_cachep) {
5a528957 389 pr_err("error: Failed to initialise inode cache\n");
1da177e4
LT
390 return -ENOMEM;
391 }
392 ret = jffs2_compressors_init();
393 if (ret) {
5a528957 394 pr_err("error: Failed to initialise compressors\n");
1da177e4
LT
395 goto out;
396 }
397 ret = jffs2_create_slab_caches();
398 if (ret) {
5a528957 399 pr_err("error: Failed to initialise slab caches\n");
1da177e4
LT
400 goto out_compressors;
401 }
402 ret = register_filesystem(&jffs2_fs_type);
403 if (ret) {
5a528957 404 pr_err("error: Failed to register filesystem\n");
1da177e4
LT
405 goto out_slab;
406 }
407 return 0;
408
409 out_slab:
410 jffs2_destroy_slab_caches();
411 out_compressors:
412 jffs2_compressors_exit();
413 out:
414 kmem_cache_destroy(jffs2_inode_cachep);
415 return ret;
416}
417
418static void __exit exit_jffs2_fs(void)
419{
420 unregister_filesystem(&jffs2_fs_type);
421 jffs2_destroy_slab_caches();
422 jffs2_compressors_exit();
8c0a8537
KS
423
424 /*
425 * Make sure all delayed rcu free inodes are flushed before we
426 * destroy cache.
427 */
428 rcu_barrier();
1da177e4
LT
429 kmem_cache_destroy(jffs2_inode_cachep);
430}
431
432module_init(init_jffs2_fs);
433module_exit(exit_jffs2_fs);
434
435MODULE_DESCRIPTION("The Journalling Flash File System, v2");
436MODULE_AUTHOR("Red Hat, Inc.");
182ec4ee 437MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
1da177e4 438 // the sake of this tag. It's Free Software.