Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
[linux-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>
ec10a24f
DH
22#include <linux/fs_context.h>
23#include <linux/fs_parser.h>
1da177e4
LT
24#include <linux/jffs2.h>
25#include <linux/pagemap.h>
acaebfd8 26#include <linux/mtd/super.h>
1da177e4
LT
27#include <linux/ctype.h>
28#include <linux/namei.h>
92abc475 29#include <linux/seq_file.h>
5f556aab 30#include <linux/exportfs.h>
1da177e4
LT
31#include "compr.h"
32#include "nodelist.h"
33
34static void jffs2_put_super(struct super_block *);
35
e18b890b 36static struct kmem_cache *jffs2_inode_cachep;
1da177e4
LT
37
38static struct inode *jffs2_alloc_inode(struct super_block *sb)
39{
4e571aba
DW
40 struct jffs2_inode_info *f;
41
fd60b288 42 f = alloc_inode_sb(sb, jffs2_inode_cachep, GFP_KERNEL);
4e571aba 43 if (!f)
1da177e4 44 return NULL;
4e571aba 45 return &f->vfs_inode;
1da177e4
LT
46}
47
db0bd7b7 48static void jffs2_free_inode(struct inode *inode)
1da177e4 49{
4fdcfab5
AV
50 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
51
52 kfree(f->target);
53 kmem_cache_free(jffs2_inode_cachep, f);
1da177e4
LT
54}
55
51cc5068 56static void jffs2_i_init_once(void *foo)
1da177e4 57{
4e571aba 58 struct jffs2_inode_info *f = foo;
1da177e4 59
4e571aba
DW
60 mutex_init(&f->sem);
61 inode_init_once(&f->vfs_inode);
1da177e4
LT
62}
63
92abc475
AS
64static const char *jffs2_compr_name(unsigned int compr)
65{
66 switch (compr) {
67 case JFFS2_COMPR_MODE_NONE:
68 return "none";
123005f3
AS
69#ifdef CONFIG_JFFS2_LZO
70 case JFFS2_COMPR_MODE_FORCELZO:
71 return "lzo";
72#endif
73#ifdef CONFIG_JFFS2_ZLIB
74 case JFFS2_COMPR_MODE_FORCEZLIB:
75 return "zlib";
76#endif
92abc475
AS
77 default:
78 /* should never happen; programmer error */
79 WARN_ON(1);
80 return "";
81 }
82}
83
34c80b1d 84static int jffs2_show_options(struct seq_file *s, struct dentry *root)
92abc475 85{
34c80b1d 86 struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb);
92abc475
AS
87 struct jffs2_mount_opts *opts = &c->mount_opts;
88
89 if (opts->override_compr)
90 seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr));
cd3ed3c7 91 if (opts->set_rp_size)
8da8ba2e 92 seq_printf(s, ",rp_size=%u", opts->rp_size / 1024);
92abc475
AS
93
94 return 0;
95}
96
1da177e4
LT
97static int jffs2_sync_fs(struct super_block *sb, int wait)
98{
99 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
100
a445f784 101#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
a788c527
DS
102 if (jffs2_is_writebuffered(c))
103 cancel_delayed_work_sync(&c->wbuf_dwork);
a445f784
AB
104#endif
105
ced22070 106 mutex_lock(&c->alloc_sem);
1da177e4 107 jffs2_flush_wbuf_pad(c);
ced22070 108 mutex_unlock(&c->alloc_sem);
1da177e4
LT
109 return 0;
110}
111
5f556aab
DW
112static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino,
113 uint32_t generation)
114{
115 /* We don't care about i_generation. We'll destroy the flash
116 before we start re-using inode numbers anyway. And even
117 if that wasn't true, we'd have other problems...*/
118 return jffs2_iget(sb, ino);
119}
120
121static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
122 int fh_len, int fh_type)
123{
124 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
125 jffs2_nfs_get_inode);
126}
127
128static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid,
129 int fh_len, int fh_type)
130{
131 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
132 jffs2_nfs_get_inode);
133}
134
135static struct dentry *jffs2_get_parent(struct dentry *child)
136{
137 struct jffs2_inode_info *f;
138 uint32_t pino;
139
e36cb0b8 140 BUG_ON(!d_is_dir(child));
5f556aab 141
2b0143b5 142 f = JFFS2_INODE_INFO(d_inode(child));
5f556aab
DW
143
144 pino = f->inocache->pino_nlink;
145
146 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
147 f->inocache->ino, pino);
148
fc64005c 149 return d_obtain_alias(jffs2_iget(child->d_sb, pino));
5f556aab
DW
150}
151
ac4cfdd6 152static const struct export_operations jffs2_export_ops = {
5f556aab
DW
153 .get_parent = jffs2_get_parent,
154 .fh_to_dentry = jffs2_fh_to_dentry,
155 .fh_to_parent = jffs2_fh_to_parent,
156};
157
92abc475
AS
158/*
159 * JFFS2 mount options.
160 *
ec10a24f 161 * Opt_source: The source device
92abc475 162 * Opt_override_compr: override default compressor
8da8ba2e 163 * Opt_rp_size: size of reserved pool in KiB
92abc475
AS
164 */
165enum {
166 Opt_override_compr,
8da8ba2e 167 Opt_rp_size,
92abc475
AS
168};
169
5eede625 170static const struct constant_table jffs2_param_compr[] = {
2710c957 171 {"none", JFFS2_COMPR_MODE_NONE },
123005f3 172#ifdef CONFIG_JFFS2_LZO
2710c957 173 {"lzo", JFFS2_COMPR_MODE_FORCELZO },
123005f3
AS
174#endif
175#ifdef CONFIG_JFFS2_ZLIB
2710c957 176 {"zlib", JFFS2_COMPR_MODE_FORCEZLIB },
123005f3 177#endif
ec10a24f
DH
178 {}
179};
180
d7167b14 181static const struct fs_parameter_spec jffs2_fs_parameters[] = {
2710c957
AV
182 fsparam_enum ("compr", Opt_override_compr, jffs2_param_compr),
183 fsparam_u32 ("rp_size", Opt_rp_size),
184 {}
185};
186
ec10a24f
DH
187static int jffs2_parse_param(struct fs_context *fc, struct fs_parameter *param)
188{
189 struct fs_parse_result result;
190 struct jffs2_sb_info *c = fc->s_fs_info;
191 int opt;
192
d7167b14 193 opt = fs_parse(fc, jffs2_fs_parameters, param, &result);
ec10a24f
DH
194 if (opt < 0)
195 return opt;
196
197 switch (opt) {
198 case Opt_override_compr:
199 c->mount_opts.compr = result.uint_32;
200 c->mount_opts.override_compr = true;
201 break;
202 case Opt_rp_size:
203 if (result.uint_32 > UINT_MAX / 1024)
204 return invalf(fc, "jffs2: rp_size unrepresentable");
a61df3c4 205 c->mount_opts.rp_size = result.uint_32 * 1024;
cd3ed3c7 206 c->mount_opts.set_rp_size = true;
ec10a24f
DH
207 break;
208 default:
209 return -EINVAL;
92abc475
AS
210 }
211
212 return 0;
213}
214
08cd274f 215static inline void jffs2_update_mount_opts(struct fs_context *fc)
216{
217 struct jffs2_sb_info *new_c = fc->s_fs_info;
218 struct jffs2_sb_info *c = JFFS2_SB_INFO(fc->root->d_sb);
219
220 mutex_lock(&c->alloc_sem);
221 if (new_c->mount_opts.override_compr) {
222 c->mount_opts.override_compr = new_c->mount_opts.override_compr;
223 c->mount_opts.compr = new_c->mount_opts.compr;
224 }
cd3ed3c7 225 if (new_c->mount_opts.set_rp_size) {
226 c->mount_opts.set_rp_size = new_c->mount_opts.set_rp_size;
08cd274f 227 c->mount_opts.rp_size = new_c->mount_opts.rp_size;
cd3ed3c7 228 }
08cd274f 229 mutex_unlock(&c->alloc_sem);
230}
231
ec10a24f 232static int jffs2_reconfigure(struct fs_context *fc)
92abc475 233{
ec10a24f 234 struct super_block *sb = fc->root->d_sb;
92abc475 235
02b9984d 236 sync_filesystem(sb);
08cd274f 237 jffs2_update_mount_opts(fc);
238
ec10a24f 239 return jffs2_do_remount_fs(sb, fc);
92abc475
AS
240}
241
ee9b6d61 242static const struct super_operations jffs2_super_operations =
1da177e4
LT
243{
244 .alloc_inode = jffs2_alloc_inode,
db0bd7b7 245 .free_inode = jffs2_free_inode,
1da177e4 246 .put_super = jffs2_put_super,
1da177e4 247 .statfs = jffs2_statfs,
b57922d9 248 .evict_inode = jffs2_evict_inode,
1da177e4 249 .dirty_inode = jffs2_dirty_inode,
92abc475 250 .show_options = jffs2_show_options,
1da177e4
LT
251 .sync_fs = jffs2_sync_fs,
252};
253
acaebfd8
DH
254/*
255 * fill in the superblock
256 */
ec10a24f 257static int jffs2_fill_super(struct super_block *sb, struct fs_context *fc)
1da177e4 258{
ec10a24f 259 struct jffs2_sb_info *c = sb->s_fs_info;
db719222 260
9c261b33 261 jffs2_dbg(1, "jffs2_get_sb_mtd():"
acaebfd8 262 " New superblock for device %d (\"%s\")\n",
9c261b33 263 sb->s_mtd->index, sb->s_mtd->name);
1da177e4 264
acaebfd8
DH
265 c->mtd = sb->s_mtd;
266 c->os_priv = sb;
92abc475 267
a61df3c4
JI
268 if (c->mount_opts.rp_size > c->mtd->size)
269 return invalf(fc, "jffs2: Too large reserve pool specified, max is %llu KB",
270 c->mtd->size / 1024);
271
acaebfd8
DH
272 /* Initialize JFFS2 superblock locks, the further initialization will
273 * be done later */
ced22070
DW
274 mutex_init(&c->alloc_sem);
275 mutex_init(&c->erase_free_sem);
b6220598
AB
276 init_waitqueue_head(&c->erase_wait);
277 init_waitqueue_head(&c->inocache_wq);
278 spin_lock_init(&c->erase_completion_lock);
279 spin_lock_init(&c->inocache_lock);
280
1da177e4 281 sb->s_op = &jffs2_super_operations;
5f556aab 282 sb->s_export_op = &jffs2_export_ops;
1751e8a6 283 sb->s_flags = sb->s_flags | SB_NOATIME;
aa98d7cf
KK
284 sb->s_xattr = jffs2_xattr_handlers;
285#ifdef CONFIG_JFFS2_FS_POSIX_ACL
1751e8a6 286 sb->s_flags |= SB_POSIXACL;
aa98d7cf 287#endif
ec10a24f
DH
288 return jffs2_do_fill_super(sb, fc);
289}
290
291static int jffs2_get_tree(struct fs_context *fc)
292{
293 return get_tree_mtd(fc, jffs2_fill_super);
294}
295
296static void jffs2_free_fc(struct fs_context *fc)
297{
298 kfree(fc->s_fs_info);
1da177e4
LT
299}
300
ec10a24f
DH
301static const struct fs_context_operations jffs2_context_ops = {
302 .free = jffs2_free_fc,
303 .parse_param = jffs2_parse_param,
304 .get_tree = jffs2_get_tree,
305 .reconfigure = jffs2_reconfigure,
306};
307
308static int jffs2_init_fs_context(struct fs_context *fc)
1da177e4 309{
ec10a24f
DH
310 struct jffs2_sb_info *ctx;
311
312 ctx = kzalloc(sizeof(struct jffs2_sb_info), GFP_KERNEL);
313 if (!ctx)
314 return -ENOMEM;
315
316 fc->s_fs_info = ctx;
317 fc->ops = &jffs2_context_ops;
318 return 0;
1da177e4
LT
319}
320
321static void jffs2_put_super (struct super_block *sb)
322{
323 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
324
9c261b33 325 jffs2_dbg(2, "%s()\n", __func__);
1da177e4 326
ced22070 327 mutex_lock(&c->alloc_sem);
1da177e4 328 jffs2_flush_wbuf_pad(c);
ced22070 329 mutex_unlock(&c->alloc_sem);
e631ddba
FH
330
331 jffs2_sum_exit(c);
332
1da177e4
LT
333 jffs2_free_ino_caches(c);
334 jffs2_free_raw_node_refs(c);
1d5cfdb0 335 kvfree(c->blocks);
1da177e4
LT
336 jffs2_flash_cleanup(c);
337 kfree(c->inocache_list);
aa98d7cf 338 jffs2_clear_xattr_subsystem(c);
327cf292 339 mtd_sync(c->mtd);
9c261b33 340 jffs2_dbg(1, "%s(): returning\n", __func__);
1da177e4
LT
341}
342
343static void jffs2_kill_sb(struct super_block *sb)
344{
345 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
c66b23c2 346 if (c && !sb_rdonly(sb))
a69dde91 347 jffs2_stop_garbage_collect_thread(c);
acaebfd8 348 kill_mtd_super(sb);
1da177e4
LT
349 kfree(c);
350}
351
352static struct file_system_type jffs2_fs_type = {
353 .owner = THIS_MODULE,
354 .name = "jffs2",
ec10a24f 355 .init_fs_context = jffs2_init_fs_context,
d7167b14 356 .parameters = jffs2_fs_parameters,
1da177e4
LT
357 .kill_sb = jffs2_kill_sb,
358};
7f78e035 359MODULE_ALIAS_FS("jffs2");
1da177e4
LT
360
361static int __init init_jffs2_fs(void)
362{
363 int ret;
364
3e68fbb5
DW
365 /* Paranoia checks for on-medium structures. If we ask GCC
366 to pack them with __attribute__((packed)) then it _also_
367 assumes that they're not aligned -- so it emits crappy
368 code on some architectures. Ideally we want an attribute
369 which means just 'no padding', without the alignment
370 thing. But GCC doesn't have that -- we have to just
371 hope the structs are the right sizes, instead. */
2ecd05ae
AD
372 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
373 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
374 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
375 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);
3e68fbb5 376
5a528957 377 pr_info("version 2.2."
2f82ce1e 378#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
1da177e4 379 " (NAND)"
e631ddba
FH
380#endif
381#ifdef CONFIG_JFFS2_SUMMARY
382 " (SUMMARY) "
1da177e4 383#endif
c00c310e 384 " © 2001-2006 Red Hat, Inc.\n");
1da177e4
LT
385
386 jffs2_inode_cachep = kmem_cache_create("jffs2_i",
387 sizeof(struct jffs2_inode_info),
fffb60f9 388 0, (SLAB_RECLAIM_ACCOUNT|
5d097056 389 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
20c2df83 390 jffs2_i_init_once);
1da177e4 391 if (!jffs2_inode_cachep) {
5a528957 392 pr_err("error: Failed to initialise inode cache\n");
1da177e4
LT
393 return -ENOMEM;
394 }
395 ret = jffs2_compressors_init();
396 if (ret) {
5a528957 397 pr_err("error: Failed to initialise compressors\n");
1da177e4
LT
398 goto out;
399 }
400 ret = jffs2_create_slab_caches();
401 if (ret) {
5a528957 402 pr_err("error: Failed to initialise slab caches\n");
1da177e4
LT
403 goto out_compressors;
404 }
405 ret = register_filesystem(&jffs2_fs_type);
406 if (ret) {
5a528957 407 pr_err("error: Failed to register filesystem\n");
1da177e4
LT
408 goto out_slab;
409 }
410 return 0;
411
412 out_slab:
413 jffs2_destroy_slab_caches();
414 out_compressors:
415 jffs2_compressors_exit();
416 out:
417 kmem_cache_destroy(jffs2_inode_cachep);
418 return ret;
419}
420
421static void __exit exit_jffs2_fs(void)
422{
423 unregister_filesystem(&jffs2_fs_type);
424 jffs2_destroy_slab_caches();
425 jffs2_compressors_exit();
8c0a8537
KS
426
427 /*
428 * Make sure all delayed rcu free inodes are flushed before we
429 * destroy cache.
430 */
431 rcu_barrier();
1da177e4
LT
432 kmem_cache_destroy(jffs2_inode_cachep);
433}
434
435module_init(init_jffs2_fs);
436module_exit(exit_jffs2_fs);
437
438MODULE_DESCRIPTION("The Journalling Flash File System, v2");
439MODULE_AUTHOR("Red Hat, Inc.");
182ec4ee 440MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
1da177e4 441 // the sake of this tag. It's Free Software.