blob: 37a8af159a1387b2755a20cf1a54b4557a142e99 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/fat/inode.c
3 *
4 * Written 1992,1993 by Werner Almesberger
5 * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner
6 * Rewritten for the constant inumbers support by Al Viro
7 *
8 * Fixes:
9 *
10 * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0
11 */
12
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/time.h>
16#include <linux/slab.h>
17#include <linux/smp_lock.h>
18#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/pagemap.h>
OGAWA Hirofumia5425d22006-01-08 01:02:10 -080020#include <linux/mpage.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/buffer_head.h>
Christoph Hellwiga5694252007-07-17 04:04:28 -070022#include <linux/exportfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/mount.h>
24#include <linux/vfs.h>
25#include <linux/parser.h>
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080026#include <linux/uio.h>
Chris Masonae78bf92006-09-29 02:00:03 -070027#include <linux/writeback.h>
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -070028#include <linux/log2.h>
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -080029#include <linux/hash.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <asm/unaligned.h>
OGAWA Hirofumi9e975da2008-11-06 12:53:46 -080031#include "fat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33#ifndef CONFIG_FAT_DEFAULT_IOCHARSET
34/* if user don't select VFAT, this is undefined. */
35#define CONFIG_FAT_DEFAULT_IOCHARSET ""
36#endif
37
38static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
39static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
40
41
42static int fat_add_cluster(struct inode *inode)
43{
44 int err, cluster;
45
46 err = fat_alloc_clusters(inode, &cluster, 1);
47 if (err)
48 return err;
49 /* FIXME: this cluster should be added after data of this
50 * cluster is writed */
51 err = fat_chain_add(inode, cluster, 1);
52 if (err)
53 fat_free_clusters(inode, cluster);
54 return err;
55}
56
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070057static inline int __fat_get_block(struct inode *inode, sector_t iblock,
58 unsigned long *max_blocks,
59 struct buffer_head *bh_result, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -070060{
61 struct super_block *sb = inode->i_sb;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080062 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080063 unsigned long mapped_blocks;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070064 sector_t phys;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080065 int err, offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -080067 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 if (err)
69 return err;
70 if (phys) {
71 map_bh(bh_result, sb, phys);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080072 *max_blocks = min(mapped_blocks, *max_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 return 0;
74 }
75 if (!create)
76 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080077
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
79 fat_fs_panic(sb, "corrupted file size (i_pos %lld, %lld)",
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070080 MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 return -EIO;
82 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080083
84 offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
85 if (!offset) {
86 /* TODO: multiple cluster allocation would be desirable. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 err = fat_add_cluster(inode);
88 if (err)
89 return err;
90 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080091 /* available blocks on this cluster */
92 mapped_blocks = sbi->sec_per_clus - offset;
93
94 *max_blocks = min(mapped_blocks, *max_blocks);
95 MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
96
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -080097 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 if (err)
99 return err;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700100
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800101 BUG_ON(!phys);
102 BUG_ON(*max_blocks != mapped_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 set_buffer_new(bh_result);
104 map_bh(bh_result, sb, phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800106 return 0;
107}
108
109static int fat_get_block(struct inode *inode, sector_t iblock,
110 struct buffer_head *bh_result, int create)
111{
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700112 struct super_block *sb = inode->i_sb;
113 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
114 int err;
115
116 err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create);
117 if (err)
118 return err;
119 bh_result->b_size = max_blocks << sb->s_blocksize_bits;
120 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800121}
122
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123static int fat_writepage(struct page *page, struct writeback_control *wbc)
124{
125 return block_write_full_page(page, fat_get_block, wbc);
126}
127
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800128static int fat_writepages(struct address_space *mapping,
129 struct writeback_control *wbc)
130{
131 return mpage_writepages(mapping, wbc, fat_get_block);
132}
133
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134static int fat_readpage(struct file *file, struct page *page)
135{
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800136 return mpage_readpage(page, fat_get_block);
137}
138
139static int fat_readpages(struct file *file, struct address_space *mapping,
140 struct list_head *pages, unsigned nr_pages)
141{
142 return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143}
144
Nick Piggind7777a22007-10-16 01:25:08 -0700145static int fat_write_begin(struct file *file, struct address_space *mapping,
146 loff_t pos, unsigned len, unsigned flags,
147 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148{
Nick Piggind7777a22007-10-16 01:25:08 -0700149 *pagep = NULL;
150 return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
151 fat_get_block,
152 &MSDOS_I(mapping->host)->mmu_private);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153}
154
Nick Piggind7777a22007-10-16 01:25:08 -0700155static int fat_write_end(struct file *file, struct address_space *mapping,
156 loff_t pos, unsigned len, unsigned copied,
157 struct page *pagep, void *fsdata)
OGAWA Hirofumief402262005-09-16 19:28:13 -0700158{
Nick Piggind7777a22007-10-16 01:25:08 -0700159 struct inode *inode = mapping->host;
160 int err;
161 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
162 if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) {
OGAWA Hirofumief402262005-09-16 19:28:13 -0700163 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
164 MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
165 mark_inode_dirty(inode);
166 }
167 return err;
168}
169
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800170static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
171 const struct iovec *iov,
172 loff_t offset, unsigned long nr_segs)
173{
174 struct file *file = iocb->ki_filp;
175 struct inode *inode = file->f_mapping->host;
176
177 if (rw == WRITE) {
178 /*
Nick Piggin4e02ed42008-10-29 14:00:55 -0700179 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800180 * so we need to update the ->mmu_private to block boundary.
181 *
182 * But we must fill the remaining area or hole by nul for
183 * updating ->mmu_private.
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800184 *
185 * Return 0, and fallback to normal buffered write.
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800186 */
187 loff_t size = offset + iov_length(iov, nr_segs);
188 if (MSDOS_I(inode)->mmu_private < size)
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800189 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800190 }
191
192 /*
193 * FAT need to use the DIO_LOCKING for avoiding the race
194 * condition of fat_get_block() and ->truncate().
195 */
196 return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700197 offset, nr_segs, fat_get_block, NULL);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800198}
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
201{
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800202 sector_t blocknr;
203
204 /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
205 mutex_lock(&mapping->host->i_mutex);
206 blocknr = generic_block_bmap(mapping, block, fat_get_block);
207 mutex_unlock(&mapping->host->i_mutex);
208
209 return blocknr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210}
211
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700212static const struct address_space_operations fat_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 .readpage = fat_readpage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800214 .readpages = fat_readpages,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 .writepage = fat_writepage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800216 .writepages = fat_writepages,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 .sync_page = block_sync_page,
Nick Piggind7777a22007-10-16 01:25:08 -0700218 .write_begin = fat_write_begin,
219 .write_end = fat_write_end,
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800220 .direct_IO = fat_direct_IO,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 .bmap = _fat_bmap
222};
223
224/*
225 * New FAT inode stuff. We do the following:
226 * a) i_ino is constant and has nothing with on-disk location.
227 * b) FAT manages its own cache of directory entries.
228 * c) *This* cache is indexed by on-disk location.
229 * d) inode has an associated directory entry, all right, but
230 * it may be unhashed.
231 * e) currently entries are stored within struct inode. That should
232 * change.
233 * f) we deal with races in the following way:
234 * 1. readdir() and lookup() do FAT-dir-cache lookup.
235 * 2. rename() unhashes the F-d-c entry and rehashes it in
236 * a new place.
237 * 3. unlink() and rmdir() unhash F-d-c entry.
238 * 4. fat_write_inode() checks whether the thing is unhashed.
239 * If it is we silently return. If it isn't we do bread(),
240 * check if the location is still valid and retry if it
241 * isn't. Otherwise we do changes.
242 * 5. Spinlock is used to protect hash/unhash/location check/lookup
243 * 6. fat_clear_inode() unhashes the F-d-c entry.
244 * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
245 * and consider negative result as cache miss.
246 */
247
248static void fat_hash_init(struct super_block *sb)
249{
250 struct msdos_sb_info *sbi = MSDOS_SB(sb);
251 int i;
252
253 spin_lock_init(&sbi->inode_hash_lock);
254 for (i = 0; i < FAT_HASH_SIZE; i++)
255 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
256}
257
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800258static inline unsigned long fat_hash(loff_t i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800260 return hash_32(i_pos, FAT_HASH_BITS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261}
262
263void fat_attach(struct inode *inode, loff_t i_pos)
264{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800265 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
266 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267
268 spin_lock(&sbi->inode_hash_lock);
269 MSDOS_I(inode)->i_pos = i_pos;
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800270 hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 spin_unlock(&sbi->inode_hash_lock);
272}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800273EXPORT_SYMBOL_GPL(fat_attach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274
275void fat_detach(struct inode *inode)
276{
277 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
278 spin_lock(&sbi->inode_hash_lock);
279 MSDOS_I(inode)->i_pos = 0;
280 hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
281 spin_unlock(&sbi->inode_hash_lock);
282}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800283EXPORT_SYMBOL_GPL(fat_detach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
285struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
286{
287 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800288 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 struct hlist_node *_p;
290 struct msdos_inode_info *i;
291 struct inode *inode = NULL;
292
293 spin_lock(&sbi->inode_hash_lock);
294 hlist_for_each_entry(i, _p, head, i_fat_hash) {
295 BUG_ON(i->vfs_inode.i_sb != sb);
296 if (i->i_pos != i_pos)
297 continue;
298 inode = igrab(&i->vfs_inode);
299 if (inode)
300 break;
301 }
302 spin_unlock(&sbi->inode_hash_lock);
303 return inode;
304}
305
306static int is_exec(unsigned char *extension)
307{
308 unsigned char *exe_extensions = "EXECOMBAT", *walk;
309
310 for (walk = exe_extensions; *walk; walk += 3)
311 if (!strncmp(extension, walk, 3))
312 return 1;
313 return 0;
314}
315
316static int fat_calc_dir_size(struct inode *inode)
317{
318 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
319 int ret, fclus, dclus;
320
321 inode->i_size = 0;
322 if (MSDOS_I(inode)->i_start == 0)
323 return 0;
324
325 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
326 if (ret < 0)
327 return ret;
328 inode->i_size = (fclus + 1) << sbi->cluster_bits;
329
330 return 0;
331}
332
333/* doesn't deal with root inode */
334static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
335{
336 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
337 int error;
338
339 MSDOS_I(inode)->i_pos = 0;
340 inode->i_uid = sbi->options.fs_uid;
341 inode->i_gid = sbi->options.fs_gid;
342 inode->i_version++;
343 inode->i_generation = get_seconds();
344
345 if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
346 inode->i_generation &= ~1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800347 inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 inode->i_op = sbi->dir_ops;
349 inode->i_fop = &fat_dir_operations;
350
351 MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
352 if (sbi->fat_bits == 32)
353 MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
354
355 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
356 error = fat_calc_dir_size(inode);
357 if (error < 0)
358 return error;
359 MSDOS_I(inode)->mmu_private = inode->i_size;
360
361 inode->i_nlink = fat_subdirs(inode);
362 } else { /* not a directory */
363 inode->i_generation |= 1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800364 inode->i_mode = fat_make_mode(sbi, de->attr,
365 ((sbi->options.showexec && !is_exec(de->name + 8))
366 ? S_IRUGO|S_IWUGO : S_IRWXUGO));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
368 if (sbi->fat_bits == 32)
369 MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
370
371 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
372 inode->i_size = le32_to_cpu(de->size);
373 inode->i_op = &fat_file_inode_operations;
374 inode->i_fop = &fat_file_operations;
375 inode->i_mapping->a_ops = &fat_aops;
376 MSDOS_I(inode)->mmu_private = inode->i_size;
377 }
378 if (de->attr & ATTR_SYS) {
379 if (sbi->options.sys_immutable)
380 inode->i_flags |= S_IMMUTABLE;
381 }
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800382 fat_save_attrs(inode, de->attr);
383
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
385 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800386
387 fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 if (sbi->options.isvfat) {
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800389 fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
390 de->cdate, de->ctime_cs);
391 fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 } else
Stephane Kardas62a36c42005-09-21 09:55:45 -0700393 inode->i_ctime = inode->i_atime = inode->i_mtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394
395 return 0;
396}
397
398struct inode *fat_build_inode(struct super_block *sb,
399 struct msdos_dir_entry *de, loff_t i_pos)
400{
401 struct inode *inode;
402 int err;
403
404 inode = fat_iget(sb, i_pos);
405 if (inode)
406 goto out;
407 inode = new_inode(sb);
408 if (!inode) {
409 inode = ERR_PTR(-ENOMEM);
410 goto out;
411 }
412 inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
413 inode->i_version = 1;
414 err = fat_fill_inode(inode, de);
415 if (err) {
416 iput(inode);
417 inode = ERR_PTR(err);
418 goto out;
419 }
420 fat_attach(inode, i_pos);
421 insert_inode_hash(inode);
422out:
423 return inode;
424}
425
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800426EXPORT_SYMBOL_GPL(fat_build_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
428static void fat_delete_inode(struct inode *inode)
429{
Mark Fashehfef26652005-09-09 13:01:31 -0700430 truncate_inode_pages(&inode->i_data, 0);
OGAWA Hirofumi3754a542008-04-28 02:16:24 -0700431 inode->i_size = 0;
432 fat_truncate(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 clear_inode(inode);
434}
435
436static void fat_clear_inode(struct inode *inode)
437{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 fat_cache_inval_inode(inode);
OGAWA Hirofumia993b542008-11-06 12:53:50 -0800439 fat_detach(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440}
441
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800442static void fat_write_super(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443{
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800444 sb->s_dirt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
446 if (!(sb->s_flags & MS_RDONLY))
447 fat_clusters_flush(sb);
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800448}
449
450static void fat_put_super(struct super_block *sb)
451{
452 struct msdos_sb_info *sbi = MSDOS_SB(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
454 if (sbi->nls_disk) {
455 unload_nls(sbi->nls_disk);
456 sbi->nls_disk = NULL;
457 sbi->options.codepage = fat_default_codepage;
458 }
459 if (sbi->nls_io) {
460 unload_nls(sbi->nls_io);
461 sbi->nls_io = NULL;
462 }
463 if (sbi->options.iocharset != fat_default_iocharset) {
464 kfree(sbi->options.iocharset);
465 sbi->options.iocharset = fat_default_iocharset;
466 }
467
468 sb->s_fs_info = NULL;
469 kfree(sbi);
470}
471
Christoph Lametere18b8902006-12-06 20:33:20 -0800472static struct kmem_cache *fat_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473
474static struct inode *fat_alloc_inode(struct super_block *sb)
475{
476 struct msdos_inode_info *ei;
Linus Torvalds8f593422008-05-19 19:53:01 -0700477 ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 if (!ei)
479 return NULL;
480 return &ei->vfs_inode;
481}
482
483static void fat_destroy_inode(struct inode *inode)
484{
485 kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
486}
487
Alexey Dobriyan51cc5062008-07-25 19:45:34 -0700488static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489{
490 struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
491
Christoph Lametera35afb82007-05-16 22:10:57 -0700492 spin_lock_init(&ei->cache_lru_lock);
493 ei->nr_caches = 0;
494 ei->cache_valid_id = FAT_CACHE_VALID + 1;
495 INIT_LIST_HEAD(&ei->cache_lru);
496 INIT_HLIST_NODE(&ei->i_fat_hash);
497 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498}
499
500static int __init fat_init_inodecache(void)
501{
502 fat_inode_cachep = kmem_cache_create("fat_inode_cache",
503 sizeof(struct msdos_inode_info),
Paul Jacksonfffb60f2006-03-24 03:16:06 -0800504 0, (SLAB_RECLAIM_ACCOUNT|
505 SLAB_MEM_SPREAD),
Paul Mundt20c2df82007-07-20 10:11:58 +0900506 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 if (fat_inode_cachep == NULL)
508 return -ENOMEM;
509 return 0;
510}
511
512static void __exit fat_destroy_inodecache(void)
513{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -0700514 kmem_cache_destroy(fat_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515}
516
517static int fat_remount(struct super_block *sb, int *flags, char *data)
518{
519 struct msdos_sb_info *sbi = MSDOS_SB(sb);
520 *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
521 return 0;
522}
523
David Howells726c3342006-06-23 02:02:58 -0700524static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525{
David Howells726c3342006-06-23 02:02:58 -0700526 struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
528 /* If the count of free cluster is still unknown, counts it here. */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -0700529 if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
David Howells726c3342006-06-23 02:02:58 -0700530 int err = fat_count_free_clusters(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 if (err)
532 return err;
533 }
534
David Howells726c3342006-06-23 02:02:58 -0700535 buf->f_type = dentry->d_sb->s_magic;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 buf->f_bsize = sbi->cluster_size;
537 buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
538 buf->f_bfree = sbi->free_clusters;
539 buf->f_bavail = sbi->free_clusters;
540 buf->f_namelen = sbi->options.isvfat ? 260 : 12;
541
542 return 0;
543}
544
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800545static inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi,
546 struct inode *inode)
547{
548 loff_t i_pos;
549#if BITS_PER_LONG == 32
550 spin_lock(&sbi->inode_hash_lock);
551#endif
552 i_pos = MSDOS_I(inode)->i_pos;
553#if BITS_PER_LONG == 32
554 spin_unlock(&sbi->inode_hash_lock);
555#endif
556 return i_pos;
557}
558
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559static int fat_write_inode(struct inode *inode, int wait)
560{
561 struct super_block *sb = inode->i_sb;
562 struct msdos_sb_info *sbi = MSDOS_SB(sb);
563 struct buffer_head *bh;
564 struct msdos_dir_entry *raw_entry;
565 loff_t i_pos;
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700566 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800568 if (inode->i_ino == MSDOS_ROOT_INO)
569 return 0;
570
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571retry:
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800572 i_pos = fat_i_pos_read(sbi, inode);
573 if (!i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 return 0;
575
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits);
577 if (!bh) {
578 printk(KERN_ERR "FAT: unable to read inode block "
579 "for updating (i_pos %lld)\n", i_pos);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700580 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 }
582 spin_lock(&sbi->inode_hash_lock);
583 if (i_pos != MSDOS_I(inode)->i_pos) {
584 spin_unlock(&sbi->inode_hash_lock);
585 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 goto retry;
587 }
588
589 raw_entry = &((struct msdos_dir_entry *) (bh->b_data))
590 [i_pos & (sbi->dir_per_block - 1)];
591 if (S_ISDIR(inode->i_mode))
592 raw_entry->size = 0;
593 else
594 raw_entry->size = cpu_to_le32(inode->i_size);
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800595 raw_entry->attr = fat_make_attrs(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
597 raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800598 fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
599 &raw_entry->date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 if (sbi->options.isvfat) {
Stephane Kardas62a36c42005-09-21 09:55:45 -0700601 __le16 atime;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800602 fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
603 &raw_entry->cdate, &raw_entry->ctime_cs);
604 fat_time_unix2fat(sbi, &inode->i_atime, &atime,
605 &raw_entry->adate, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 }
607 spin_unlock(&sbi->inode_hash_lock);
608 mark_buffer_dirty(bh);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700609 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 if (wait)
611 err = sync_dirty_buffer(bh);
612 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 return err;
614}
615
616int fat_sync_inode(struct inode *inode)
617{
618 return fat_write_inode(inode, 1);
619}
620
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800621EXPORT_SYMBOL_GPL(fat_sync_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622
623static int fat_show_options(struct seq_file *m, struct vfsmount *mnt);
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800624static const struct super_operations fat_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 .alloc_inode = fat_alloc_inode,
626 .destroy_inode = fat_destroy_inode,
627 .write_inode = fat_write_inode,
628 .delete_inode = fat_delete_inode,
629 .put_super = fat_put_super,
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800630 .write_super = fat_write_super,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 .statfs = fat_statfs,
632 .clear_inode = fat_clear_inode,
633 .remount_fs = fat_remount,
634
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 .show_options = fat_show_options,
636};
637
638/*
639 * a FAT file handle with fhtype 3 is
640 * 0/ i_ino - for fast, reliable lookup if still in the cache
641 * 1/ i_generation - to see if i_ino is still valid
642 * bit 0 == 0 iff directory
643 * 2/ i_pos(8-39) - if ino has changed, but still in cache
644 * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos
645 * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc
646 *
647 * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum
648 * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits
649 * of i_logstart is used to store the directory entry offset.
650 */
651
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700652static struct dentry *fat_fh_to_dentry(struct super_block *sb,
653 struct fid *fid, int fh_len, int fh_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654{
655 struct inode *inode = NULL;
656 struct dentry *result;
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700657 u32 *fh = fid->raw;
658
659 if (fh_len < 5 || fh_type != 3)
660 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
David Howells17f95a72008-02-07 00:15:38 -0800662 inode = ilookup(sb, fh[0]);
663 if (!inode || inode->i_generation != fh[1]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 if (inode)
665 iput(inode);
666 inode = NULL;
667 }
668 if (!inode) {
669 loff_t i_pos;
670 int i_logstart = fh[3] & 0x0fffffff;
671
672 i_pos = (loff_t)fh[2] << 8;
673 i_pos |= ((fh[3] >> 24) & 0xf0) | (fh[4] >> 28);
674
675 /* try 2 - see if i_pos is in F-d-c
676 * require i_logstart to be the same
677 * Will fail if you truncate and then re-write
678 */
679
680 inode = fat_iget(sb, i_pos);
681 if (inode && MSDOS_I(inode)->i_logstart != i_logstart) {
682 iput(inode);
683 inode = NULL;
684 }
685 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686
Christoph Hellwig44003722008-08-11 15:49:04 +0200687 /*
688 * For now, do nothing if the inode is not found.
689 *
690 * What we could do is:
691 *
692 * - follow the file starting at fh[4], and record the ".." entry,
693 * and the name of the fh[2] entry.
694 * - then follow the ".." file finding the next step up.
695 *
696 * This way we build a path to the root of the tree. If this works, we
697 * lookup the path and so get this inode into the cache. Finally try
698 * the fat_iget lookup again. If that fails, then we are totally out
699 * of luck. But all that is for another day
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 */
Christoph Hellwig44003722008-08-11 15:49:04 +0200701 result = d_obtain_alias(inode);
702 if (!IS_ERR(result))
703 result->d_op = sb->s_root->d_op;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 return result;
705}
706
707static int
708fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable)
709{
710 int len = *lenp;
711 struct inode *inode = de->d_inode;
712 u32 ipos_h, ipos_m, ipos_l;
713
714 if (len < 5)
715 return 255; /* no room */
716
717 ipos_h = MSDOS_I(inode)->i_pos >> 8;
718 ipos_m = (MSDOS_I(inode)->i_pos & 0xf0) << 24;
719 ipos_l = (MSDOS_I(inode)->i_pos & 0x0f) << 28;
720 *lenp = 5;
721 fh[0] = inode->i_ino;
722 fh[1] = inode->i_generation;
723 fh[2] = ipos_h;
724 fh[3] = ipos_m | MSDOS_I(inode)->i_logstart;
725 spin_lock(&de->d_lock);
726 fh[4] = ipos_l | MSDOS_I(de->d_parent->d_inode)->i_logstart;
727 spin_unlock(&de->d_lock);
728 return 3;
729}
730
731static struct dentry *fat_get_parent(struct dentry *child)
732{
Linus Torvalds8f593422008-05-19 19:53:01 -0700733 struct super_block *sb = child->d_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 struct buffer_head *bh;
735 struct msdos_dir_entry *de;
736 loff_t i_pos;
737 struct dentry *parent;
738 struct inode *inode;
739 int err;
740
Linus Torvalds8f593422008-05-19 19:53:01 -0700741 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
743 err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos);
744 if (err) {
745 parent = ERR_PTR(err);
746 goto out;
747 }
Linus Torvalds8f593422008-05-19 19:53:01 -0700748 inode = fat_build_inode(sb, de, i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 brelse(bh);
Christoph Hellwig44003722008-08-11 15:49:04 +0200750
751 parent = d_obtain_alias(inode);
Christoph Hellwig5a6bb102008-11-12 07:48:01 +0900752 if (!IS_ERR(parent))
753 parent->d_op = sb->s_root->d_op;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700755 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756
757 return parent;
758}
759
Christoph Hellwig39655162007-10-21 16:42:17 -0700760static const struct export_operations fat_export_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 .encode_fh = fat_encode_fh,
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700762 .fh_to_dentry = fat_fh_to_dentry,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 .get_parent = fat_get_parent,
764};
765
766static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
767{
768 struct msdos_sb_info *sbi = MSDOS_SB(mnt->mnt_sb);
769 struct fat_mount_options *opts = &sbi->options;
770 int isvfat = opts->isvfat;
771
772 if (opts->fs_uid != 0)
773 seq_printf(m, ",uid=%u", opts->fs_uid);
774 if (opts->fs_gid != 0)
775 seq_printf(m, ",gid=%u", opts->fs_gid);
776 seq_printf(m, ",fmask=%04o", opts->fs_fmask);
777 seq_printf(m, ",dmask=%04o", opts->fs_dmask);
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700778 if (opts->allow_utime)
779 seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780 if (sbi->nls_disk)
781 seq_printf(m, ",codepage=%s", sbi->nls_disk->charset);
782 if (isvfat) {
783 if (sbi->nls_io)
784 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
785
786 switch (opts->shortname) {
787 case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
788 seq_puts(m, ",shortname=win95");
789 break;
790 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
791 seq_puts(m, ",shortname=winnt");
792 break;
793 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
794 seq_puts(m, ",shortname=mixed");
795 break;
796 case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
797 /* seq_puts(m, ",shortname=lower"); */
798 break;
799 default:
800 seq_puts(m, ",shortname=unknown");
801 break;
802 }
803 }
804 if (opts->name_check != 'n')
805 seq_printf(m, ",check=%c", opts->name_check);
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700806 if (opts->usefree)
807 seq_puts(m, ",usefree");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 if (opts->quiet)
809 seq_puts(m, ",quiet");
810 if (opts->showexec)
811 seq_puts(m, ",showexec");
812 if (opts->sys_immutable)
813 seq_puts(m, ",sys_immutable");
814 if (!isvfat) {
815 if (opts->dotsOK)
816 seq_puts(m, ",dotsOK=yes");
817 if (opts->nocase)
818 seq_puts(m, ",nocase");
819 } else {
820 if (opts->utf8)
821 seq_puts(m, ",utf8");
822 if (opts->unicode_xlate)
823 seq_puts(m, ",uni_xlate");
824 if (!opts->numtail)
825 seq_puts(m, ",nonumtail");
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800826 if (opts->rodir)
827 seq_puts(m, ",rodir");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 }
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800829 if (opts->flush)
Miklos Szeredic1fca3b2008-02-08 04:21:42 -0800830 seq_puts(m, ",flush");
Joe Petersonb271e062008-07-25 01:46:47 -0700831 if (opts->tz_utc)
832 seq_puts(m, ",tz=UTC");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833
834 return 0;
835}
836
837enum {
838 Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700839 Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage,
840 Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug,
841 Opt_immutable, Opt_dots, Opt_nodots,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
843 Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
844 Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800845 Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846};
847
Steven Whitehousea447c092008-10-13 10:46:57 +0100848static const match_table_t fat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 {Opt_check_r, "check=relaxed"},
850 {Opt_check_s, "check=strict"},
851 {Opt_check_n, "check=normal"},
852 {Opt_check_r, "check=r"},
853 {Opt_check_s, "check=s"},
854 {Opt_check_n, "check=n"},
855 {Opt_uid, "uid=%u"},
856 {Opt_gid, "gid=%u"},
857 {Opt_umask, "umask=%o"},
858 {Opt_dmask, "dmask=%o"},
859 {Opt_fmask, "fmask=%o"},
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700860 {Opt_allow_utime, "allow_utime=%o"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 {Opt_codepage, "codepage=%u"},
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700862 {Opt_usefree, "usefree"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 {Opt_nocase, "nocase"},
864 {Opt_quiet, "quiet"},
865 {Opt_showexec, "showexec"},
866 {Opt_debug, "debug"},
867 {Opt_immutable, "sys_immutable"},
868 {Opt_obsolate, "conv=binary"},
869 {Opt_obsolate, "conv=text"},
870 {Opt_obsolate, "conv=auto"},
871 {Opt_obsolate, "conv=b"},
872 {Opt_obsolate, "conv=t"},
873 {Opt_obsolate, "conv=a"},
874 {Opt_obsolate, "fat=%u"},
875 {Opt_obsolate, "blocksize=%u"},
876 {Opt_obsolate, "cvf_format=%20s"},
877 {Opt_obsolate, "cvf_options=%100s"},
878 {Opt_obsolate, "posix"},
Chris Masonae78bf92006-09-29 02:00:03 -0700879 {Opt_flush, "flush"},
Joe Petersonb271e062008-07-25 01:46:47 -0700880 {Opt_tz_utc, "tz=UTC"},
Chris Masonae78bf92006-09-29 02:00:03 -0700881 {Opt_err, NULL},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882};
Steven Whitehousea447c092008-10-13 10:46:57 +0100883static const match_table_t msdos_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 {Opt_nodots, "nodots"},
885 {Opt_nodots, "dotsOK=no"},
886 {Opt_dots, "dots"},
887 {Opt_dots, "dotsOK=yes"},
888 {Opt_err, NULL}
889};
Steven Whitehousea447c092008-10-13 10:46:57 +0100890static const match_table_t vfat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891 {Opt_charset, "iocharset=%s"},
892 {Opt_shortname_lower, "shortname=lower"},
893 {Opt_shortname_win95, "shortname=win95"},
894 {Opt_shortname_winnt, "shortname=winnt"},
895 {Opt_shortname_mixed, "shortname=mixed"},
896 {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
897 {Opt_utf8_no, "utf8=no"},
898 {Opt_utf8_no, "utf8=false"},
899 {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
900 {Opt_utf8_yes, "utf8=yes"},
901 {Opt_utf8_yes, "utf8=true"},
902 {Opt_utf8_yes, "utf8"},
903 {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
904 {Opt_uni_xl_no, "uni_xlate=no"},
905 {Opt_uni_xl_no, "uni_xlate=false"},
906 {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
907 {Opt_uni_xl_yes, "uni_xlate=yes"},
908 {Opt_uni_xl_yes, "uni_xlate=true"},
909 {Opt_uni_xl_yes, "uni_xlate"},
910 {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
911 {Opt_nonumtail_no, "nonumtail=no"},
912 {Opt_nonumtail_no, "nonumtail=false"},
913 {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
914 {Opt_nonumtail_yes, "nonumtail=yes"},
915 {Opt_nonumtail_yes, "nonumtail=true"},
916 {Opt_nonumtail_yes, "nonumtail"},
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800917 {Opt_rodir, "rodir"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 {Opt_err, NULL}
919};
920
Christoph Hellwig41a34a42005-11-08 21:34:57 -0800921static int parse_options(char *options, int is_vfat, int silent, int *debug,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922 struct fat_mount_options *opts)
923{
924 char *p;
925 substring_t args[MAX_OPT_ARGS];
926 int option;
927 char *iocharset;
928
929 opts->isvfat = is_vfat;
930
931 opts->fs_uid = current->uid;
932 opts->fs_gid = current->gid;
933 opts->fs_fmask = opts->fs_dmask = current->fs->umask;
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700934 opts->allow_utime = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 opts->codepage = fat_default_codepage;
936 opts->iocharset = fat_default_iocharset;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800937 if (is_vfat) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800939 opts->rodir = 0;
940 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941 opts->shortname = 0;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800942 opts->rodir = 1;
943 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 opts->name_check = 'n';
945 opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
946 opts->utf8 = opts->unicode_xlate = 0;
947 opts->numtail = 1;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700948 opts->usefree = opts->nocase = 0;
Joe Petersonb271e062008-07-25 01:46:47 -0700949 opts->tz_utc = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950 *debug = 0;
951
952 if (!options)
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -0700953 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954
955 while ((p = strsep(&options, ",")) != NULL) {
956 int token;
957 if (!*p)
958 continue;
959
960 token = match_token(p, fat_tokens, args);
961 if (token == Opt_err) {
962 if (is_vfat)
963 token = match_token(p, vfat_tokens, args);
964 else
965 token = match_token(p, msdos_tokens, args);
966 }
967 switch (token) {
968 case Opt_check_s:
969 opts->name_check = 's';
970 break;
971 case Opt_check_r:
972 opts->name_check = 'r';
973 break;
974 case Opt_check_n:
975 opts->name_check = 'n';
976 break;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700977 case Opt_usefree:
978 opts->usefree = 1;
979 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 case Opt_nocase:
981 if (!is_vfat)
982 opts->nocase = 1;
983 else {
984 /* for backward compatibility */
985 opts->shortname = VFAT_SFN_DISPLAY_WIN95
986 | VFAT_SFN_CREATE_WIN95;
987 }
988 break;
989 case Opt_quiet:
990 opts->quiet = 1;
991 break;
992 case Opt_showexec:
993 opts->showexec = 1;
994 break;
995 case Opt_debug:
996 *debug = 1;
997 break;
998 case Opt_immutable:
999 opts->sys_immutable = 1;
1000 break;
1001 case Opt_uid:
1002 if (match_int(&args[0], &option))
1003 return 0;
1004 opts->fs_uid = option;
1005 break;
1006 case Opt_gid:
1007 if (match_int(&args[0], &option))
1008 return 0;
1009 opts->fs_gid = option;
1010 break;
1011 case Opt_umask:
1012 if (match_octal(&args[0], &option))
1013 return 0;
1014 opts->fs_fmask = opts->fs_dmask = option;
1015 break;
1016 case Opt_dmask:
1017 if (match_octal(&args[0], &option))
1018 return 0;
1019 opts->fs_dmask = option;
1020 break;
1021 case Opt_fmask:
1022 if (match_octal(&args[0], &option))
1023 return 0;
1024 opts->fs_fmask = option;
1025 break;
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001026 case Opt_allow_utime:
1027 if (match_octal(&args[0], &option))
1028 return 0;
1029 opts->allow_utime = option & (S_IWGRP | S_IWOTH);
1030 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031 case Opt_codepage:
1032 if (match_int(&args[0], &option))
1033 return 0;
1034 opts->codepage = option;
1035 break;
Chris Masonae78bf92006-09-29 02:00:03 -07001036 case Opt_flush:
1037 opts->flush = 1;
1038 break;
Joe Petersonb271e062008-07-25 01:46:47 -07001039 case Opt_tz_utc:
1040 opts->tz_utc = 1;
1041 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042
1043 /* msdos specific */
1044 case Opt_dots:
1045 opts->dotsOK = 1;
1046 break;
1047 case Opt_nodots:
1048 opts->dotsOK = 0;
1049 break;
1050
1051 /* vfat specific */
1052 case Opt_charset:
1053 if (opts->iocharset != fat_default_iocharset)
1054 kfree(opts->iocharset);
1055 iocharset = match_strdup(&args[0]);
1056 if (!iocharset)
1057 return -ENOMEM;
1058 opts->iocharset = iocharset;
1059 break;
1060 case Opt_shortname_lower:
1061 opts->shortname = VFAT_SFN_DISPLAY_LOWER
1062 | VFAT_SFN_CREATE_WIN95;
1063 break;
1064 case Opt_shortname_win95:
1065 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1066 | VFAT_SFN_CREATE_WIN95;
1067 break;
1068 case Opt_shortname_winnt:
1069 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1070 | VFAT_SFN_CREATE_WINNT;
1071 break;
1072 case Opt_shortname_mixed:
1073 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1074 | VFAT_SFN_CREATE_WIN95;
1075 break;
1076 case Opt_utf8_no: /* 0 or no or false */
1077 opts->utf8 = 0;
1078 break;
1079 case Opt_utf8_yes: /* empty or 1 or yes or true */
1080 opts->utf8 = 1;
1081 break;
1082 case Opt_uni_xl_no: /* 0 or no or false */
1083 opts->unicode_xlate = 0;
1084 break;
1085 case Opt_uni_xl_yes: /* empty or 1 or yes or true */
1086 opts->unicode_xlate = 1;
1087 break;
1088 case Opt_nonumtail_no: /* 0 or no or false */
1089 opts->numtail = 1; /* negated option */
1090 break;
1091 case Opt_nonumtail_yes: /* empty or 1 or yes or true */
1092 opts->numtail = 0; /* negated option */
1093 break;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001094 case Opt_rodir:
1095 opts->rodir = 1;
1096 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097
1098 /* obsolete mount options */
1099 case Opt_obsolate:
1100 printk(KERN_INFO "FAT: \"%s\" option is obsolete, "
1101 "not supported now\n", p);
1102 break;
1103 /* unknown option */
1104 default:
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001105 if (!silent) {
1106 printk(KERN_ERR
1107 "FAT: Unrecognized mount option \"%s\" "
1108 "or missing value\n", p);
1109 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 return -EINVAL;
1111 }
1112 }
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001113
1114out:
Alexey Dobriyan4de151d2006-03-22 00:13:35 +01001115 /* UTF-8 doesn't provide FAT semantics */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 if (!strcmp(opts->iocharset, "utf8")) {
1117 printk(KERN_ERR "FAT: utf8 is not a recommended IO charset"
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001118 " for FAT filesystems, filesystem will be "
1119 "case sensitive!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120 }
1121
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001122 /* If user doesn't specify allow_utime, it's initialized from dmask. */
1123 if (opts->allow_utime == (unsigned short)-1)
1124 opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125 if (opts->unicode_xlate)
1126 opts->utf8 = 0;
1127
1128 return 0;
1129}
1130
1131static int fat_read_root(struct inode *inode)
1132{
1133 struct super_block *sb = inode->i_sb;
1134 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1135 int error;
1136
1137 MSDOS_I(inode)->i_pos = 0;
1138 inode->i_uid = sbi->options.fs_uid;
1139 inode->i_gid = sbi->options.fs_gid;
1140 inode->i_version++;
1141 inode->i_generation = 0;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001142 inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 inode->i_op = sbi->dir_ops;
1144 inode->i_fop = &fat_dir_operations;
1145 if (sbi->fat_bits == 32) {
1146 MSDOS_I(inode)->i_start = sbi->root_cluster;
1147 error = fat_calc_dir_size(inode);
1148 if (error < 0)
1149 return error;
1150 } else {
1151 MSDOS_I(inode)->i_start = 0;
1152 inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
1153 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
1155 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
1156 MSDOS_I(inode)->i_logstart = 0;
1157 MSDOS_I(inode)->mmu_private = inode->i_size;
1158
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001159 fat_save_attrs(inode, ATTR_DIR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
1161 inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
1162 inode->i_nlink = fat_subdirs(inode)+2;
1163
1164 return 0;
1165}
1166
1167/*
1168 * Read the super block of an MS-DOS FS.
1169 */
1170int fat_fill_super(struct super_block *sb, void *data, int silent,
Arjan van de Ven754661f2007-02-12 00:55:38 -08001171 const struct inode_operations *fs_dir_inode_ops, int isvfat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172{
1173 struct inode *root_inode = NULL;
1174 struct buffer_head *bh;
1175 struct fat_boot_sector *b;
1176 struct msdos_sb_info *sbi;
1177 u16 logical_sector_size;
1178 u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
1179 int debug;
1180 unsigned int media;
1181 long error;
1182 char buf[50];
1183
Linus Torvalds8f593422008-05-19 19:53:01 -07001184 /*
1185 * GFP_KERNEL is ok here, because while we do hold the
1186 * supeblock lock, memory pressure can't call back into
1187 * the filesystem, since we're only just about to mount
1188 * it and have no inodes etc active!
1189 */
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -07001190 sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 if (!sbi)
1192 return -ENOMEM;
1193 sb->s_fs_info = sbi;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001194
1195 sb->s_flags |= MS_NODIRATIME;
1196 sb->s_magic = MSDOS_SUPER_MAGIC;
1197 sb->s_op = &fat_sops;
1198 sb->s_export_op = &fat_export_ops;
1199 sbi->dir_ops = fs_dir_inode_ops;
1200
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001201 error = parse_options(data, isvfat, silent, &debug, &sbi->options);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001202 if (error)
1203 goto out_fail;
1204
1205 error = -EIO;
1206 sb_min_blocksize(sb, 512);
1207 bh = sb_bread(sb, 0);
1208 if (bh == NULL) {
1209 printk(KERN_ERR "FAT: unable to read boot sector\n");
1210 goto out_fail;
1211 }
1212
1213 b = (struct fat_boot_sector *) bh->b_data;
1214 if (!b->reserved) {
1215 if (!silent)
1216 printk(KERN_ERR "FAT: bogus number of reserved sectors\n");
1217 brelse(bh);
1218 goto out_invalid;
1219 }
1220 if (!b->fats) {
1221 if (!silent)
1222 printk(KERN_ERR "FAT: bogus number of FAT structure\n");
1223 brelse(bh);
1224 goto out_invalid;
1225 }
1226
1227 /*
1228 * Earlier we checked here that b->secs_track and b->head are nonzero,
1229 * but it turns out valid FAT filesystems can have zero there.
1230 */
1231
1232 media = b->media;
Andrew Morton73f20e52008-04-28 02:16:30 -07001233 if (!fat_valid_media(media)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 if (!silent)
1235 printk(KERN_ERR "FAT: invalid media value (0x%02x)\n",
1236 media);
1237 brelse(bh);
1238 goto out_invalid;
1239 }
Harvey Harrison803f4452008-04-29 01:03:43 -07001240 logical_sector_size = get_unaligned_le16(&b->sector_size);
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -07001241 if (!is_power_of_2(logical_sector_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242 || (logical_sector_size < 512)
Olof Johansson9f354852008-04-28 02:16:32 -07001243 || (logical_sector_size > 4096)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001244 if (!silent)
1245 printk(KERN_ERR "FAT: bogus logical sector size %u\n",
1246 logical_sector_size);
1247 brelse(bh);
1248 goto out_invalid;
1249 }
1250 sbi->sec_per_clus = b->sec_per_clus;
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -07001251 if (!is_power_of_2(sbi->sec_per_clus)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252 if (!silent)
1253 printk(KERN_ERR "FAT: bogus sectors per cluster %u\n",
1254 sbi->sec_per_clus);
1255 brelse(bh);
1256 goto out_invalid;
1257 }
1258
1259 if (logical_sector_size < sb->s_blocksize) {
1260 printk(KERN_ERR "FAT: logical sector size too small for device"
1261 " (logical sector size = %u)\n", logical_sector_size);
1262 brelse(bh);
1263 goto out_fail;
1264 }
1265 if (logical_sector_size > sb->s_blocksize) {
1266 brelse(bh);
1267
1268 if (!sb_set_blocksize(sb, logical_sector_size)) {
1269 printk(KERN_ERR "FAT: unable to set blocksize %u\n",
1270 logical_sector_size);
1271 goto out_fail;
1272 }
1273 bh = sb_bread(sb, 0);
1274 if (bh == NULL) {
1275 printk(KERN_ERR "FAT: unable to read boot sector"
1276 " (logical sector size = %lu)\n",
1277 sb->s_blocksize);
1278 goto out_fail;
1279 }
1280 b = (struct fat_boot_sector *) bh->b_data;
1281 }
1282
1283 sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
1284 sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
1285 sbi->fats = b->fats;
1286 sbi->fat_bits = 0; /* Don't know yet */
1287 sbi->fat_start = le16_to_cpu(b->reserved);
1288 sbi->fat_length = le16_to_cpu(b->fat_length);
1289 sbi->root_cluster = 0;
1290 sbi->free_clusters = -1; /* Don't know yet */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001291 sbi->free_clus_valid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 sbi->prev_free = FAT_START_ENT;
1293
1294 if (!sbi->fat_length && b->fat32_length) {
1295 struct fat_boot_fsinfo *fsinfo;
1296 struct buffer_head *fsinfo_bh;
1297
1298 /* Must be FAT32 */
1299 sbi->fat_bits = 32;
1300 sbi->fat_length = le32_to_cpu(b->fat32_length);
1301 sbi->root_cluster = le32_to_cpu(b->root_cluster);
1302
1303 sb->s_maxbytes = 0xffffffff;
1304
1305 /* MC - if info_sector is 0, don't multiply by 0 */
1306 sbi->fsinfo_sector = le16_to_cpu(b->info_sector);
1307 if (sbi->fsinfo_sector == 0)
1308 sbi->fsinfo_sector = 1;
1309
1310 fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
1311 if (fsinfo_bh == NULL) {
1312 printk(KERN_ERR "FAT: bread failed, FSINFO block"
1313 " (sector = %lu)\n", sbi->fsinfo_sector);
1314 brelse(bh);
1315 goto out_fail;
1316 }
1317
1318 fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
1319 if (!IS_FSINFO(fsinfo)) {
Vegard Nossumb4cf9c32008-02-06 01:36:36 -08001320 printk(KERN_WARNING "FAT: Invalid FSINFO signature: "
1321 "0x%08x, 0x%08x (sector = %lu)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 le32_to_cpu(fsinfo->signature1),
1323 le32_to_cpu(fsinfo->signature2),
1324 sbi->fsinfo_sector);
1325 } else {
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001326 if (sbi->options.usefree)
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001327 sbi->free_clus_valid = 1;
1328 sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329 sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
1330 }
1331
1332 brelse(fsinfo_bh);
1333 }
1334
1335 sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
1336 sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
1337
1338 sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
Harvey Harrison803f4452008-04-29 01:03:43 -07001339 sbi->dir_entries = get_unaligned_le16(&b->dir_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
1341 if (!silent)
1342 printk(KERN_ERR "FAT: bogus directroy-entries per block"
1343 " (%u)\n", sbi->dir_entries);
1344 brelse(bh);
1345 goto out_invalid;
1346 }
1347
1348 rootdir_sectors = sbi->dir_entries
1349 * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
1350 sbi->data_start = sbi->dir_start + rootdir_sectors;
Harvey Harrison803f4452008-04-29 01:03:43 -07001351 total_sectors = get_unaligned_le16(&b->sectors);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352 if (total_sectors == 0)
1353 total_sectors = le32_to_cpu(b->total_sect);
1354
1355 total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
1356
1357 if (sbi->fat_bits != 32)
1358 sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
1359
1360 /* check that FAT table does not overflow */
1361 fat_clusters = sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
1362 total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
1363 if (total_clusters > MAX_FAT(sb)) {
1364 if (!silent)
1365 printk(KERN_ERR "FAT: count of clusters too big (%u)\n",
1366 total_clusters);
1367 brelse(bh);
1368 goto out_invalid;
1369 }
1370
1371 sbi->max_cluster = total_clusters + FAT_START_ENT;
1372 /* check the free_clusters, it's not necessarily correct */
1373 if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
1374 sbi->free_clusters = -1;
1375 /* check the prev_free, it's not necessarily correct */
1376 sbi->prev_free %= sbi->max_cluster;
1377 if (sbi->prev_free < FAT_START_ENT)
1378 sbi->prev_free = FAT_START_ENT;
1379
1380 brelse(bh);
1381
1382 /* set up enough so that it can read an inode */
1383 fat_hash_init(sb);
1384 fat_ent_access_init(sb);
1385
1386 /*
1387 * The low byte of FAT's first entry must have same value with
1388 * media-field. But in real world, too many devices is
1389 * writing wrong value. So, removed that validity check.
1390 *
1391 * if (FAT_FIRST_ENT(sb, media) != first)
1392 */
1393
1394 error = -EINVAL;
1395 sprintf(buf, "cp%d", sbi->options.codepage);
1396 sbi->nls_disk = load_nls(buf);
1397 if (!sbi->nls_disk) {
1398 printk(KERN_ERR "FAT: codepage %s not found\n", buf);
1399 goto out_fail;
1400 }
1401
1402 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1403 if (sbi->options.isvfat) {
1404 sbi->nls_io = load_nls(sbi->options.iocharset);
1405 if (!sbi->nls_io) {
1406 printk(KERN_ERR "FAT: IO charset %s not found\n",
1407 sbi->options.iocharset);
1408 goto out_fail;
1409 }
1410 }
1411
1412 error = -ENOMEM;
1413 root_inode = new_inode(sb);
1414 if (!root_inode)
1415 goto out_fail;
1416 root_inode->i_ino = MSDOS_ROOT_INO;
1417 root_inode->i_version = 1;
1418 error = fat_read_root(root_inode);
1419 if (error < 0)
1420 goto out_fail;
1421 error = -ENOMEM;
1422 insert_inode_hash(root_inode);
1423 sb->s_root = d_alloc_root(root_inode);
1424 if (!sb->s_root) {
1425 printk(KERN_ERR "FAT: get root inode failed\n");
1426 goto out_fail;
1427 }
1428
1429 return 0;
1430
1431out_invalid:
1432 error = -EINVAL;
1433 if (!silent)
1434 printk(KERN_INFO "VFS: Can't find a valid FAT filesystem"
1435 " on dev %s.\n", sb->s_id);
1436
1437out_fail:
1438 if (root_inode)
1439 iput(root_inode);
1440 if (sbi->nls_io)
1441 unload_nls(sbi->nls_io);
1442 if (sbi->nls_disk)
1443 unload_nls(sbi->nls_disk);
1444 if (sbi->options.iocharset != fat_default_iocharset)
1445 kfree(sbi->options.iocharset);
1446 sb->s_fs_info = NULL;
1447 kfree(sbi);
1448 return error;
1449}
1450
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -08001451EXPORT_SYMBOL_GPL(fat_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001452
Chris Masonae78bf92006-09-29 02:00:03 -07001453/*
1454 * helper function for fat_flush_inodes. This writes both the inode
1455 * and the file data blocks, waiting for in flight data blocks before
1456 * the start of the call. It does not wait for any io started
1457 * during the call
1458 */
1459static int writeback_inode(struct inode *inode)
1460{
1461
1462 int ret;
1463 struct address_space *mapping = inode->i_mapping;
1464 struct writeback_control wbc = {
1465 .sync_mode = WB_SYNC_NONE,
1466 .nr_to_write = 0,
1467 };
1468 /* if we used WB_SYNC_ALL, sync_inode waits for the io for the
1469 * inode to finish. So WB_SYNC_NONE is sent down to sync_inode
1470 * and filemap_fdatawrite is used for the data blocks
1471 */
1472 ret = sync_inode(inode, &wbc);
1473 if (!ret)
1474 ret = filemap_fdatawrite(mapping);
1475 return ret;
1476}
1477
1478/*
1479 * write data and metadata corresponding to i1 and i2. The io is
1480 * started but we do not wait for any of it to finish.
1481 *
1482 * filemap_flush is used for the block device, so if there is a dirty
1483 * page for a block already in flight, we will not wait and start the
1484 * io over again
1485 */
1486int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
1487{
1488 int ret = 0;
1489 if (!MSDOS_SB(sb)->options.flush)
1490 return 0;
1491 if (i1)
1492 ret = writeback_inode(i1);
1493 if (!ret && i2)
1494 ret = writeback_inode(i2);
Eric Sesterhenn97e860d2006-10-11 01:21:59 -07001495 if (!ret) {
Chris Masonae78bf92006-09-29 02:00:03 -07001496 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
1497 ret = filemap_flush(mapping);
1498 }
1499 return ret;
1500}
1501EXPORT_SYMBOL_GPL(fat_flush_inodes);
1502
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503static int __init init_fat_fs(void)
1504{
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001505 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001507 err = fat_cache_init();
1508 if (err)
1509 return err;
1510
1511 err = fat_init_inodecache();
1512 if (err)
1513 goto failed;
1514
1515 return 0;
1516
1517failed:
1518 fat_cache_destroy();
1519 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520}
1521
1522static void __exit exit_fat_fs(void)
1523{
1524 fat_cache_destroy();
1525 fat_destroy_inodecache();
1526}
1527
1528module_init(init_fat_fs)
1529module_exit(exit_fat_fs)
1530
1531MODULE_LICENSE("GPL");