blob: 5942fec22c65ddacec9efd25467ae039784884c6 [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/pagemap.h>
OGAWA Hirofumia5425d22006-01-08 01:02:10 -080019#include <linux/mpage.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/buffer_head.h>
Christoph Hellwiga5694252007-07-17 04:04:28 -070021#include <linux/exportfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/mount.h>
23#include <linux/vfs.h>
24#include <linux/parser.h>
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080025#include <linux/uio.h>
Chris Masonae78bf92006-09-29 02:00:03 -070026#include <linux/writeback.h>
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -070027#include <linux/log2.h>
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -080028#include <linux/hash.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <asm/unaligned.h>
OGAWA Hirofumi9e975da2008-11-06 12:53:46 -080030#include "fat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#ifndef CONFIG_FAT_DEFAULT_IOCHARSET
33/* if user don't select VFAT, this is undefined. */
34#define CONFIG_FAT_DEFAULT_IOCHARSET ""
35#endif
36
37static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
38static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
39
40
41static int fat_add_cluster(struct inode *inode)
42{
43 int err, cluster;
44
45 err = fat_alloc_clusters(inode, &cluster, 1);
46 if (err)
47 return err;
48 /* FIXME: this cluster should be added after data of this
49 * cluster is writed */
50 err = fat_chain_add(inode, cluster, 1);
51 if (err)
52 fat_free_clusters(inode, cluster);
53 return err;
54}
55
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070056static inline int __fat_get_block(struct inode *inode, sector_t iblock,
57 unsigned long *max_blocks,
58 struct buffer_head *bh_result, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
60 struct super_block *sb = inode->i_sb;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080061 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080062 unsigned long mapped_blocks;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070063 sector_t phys;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080064 int err, offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -080066 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 if (err)
68 return err;
69 if (phys) {
70 map_bh(bh_result, sb, phys);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080071 *max_blocks = min(mapped_blocks, *max_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 return 0;
73 }
74 if (!create)
75 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080076
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
Denis Karpov85c78592009-06-04 02:34:22 +090078 fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)",
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070079 MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 return -EIO;
81 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080082
83 offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
84 if (!offset) {
85 /* TODO: multiple cluster allocation would be desirable. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 err = fat_add_cluster(inode);
87 if (err)
88 return err;
89 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080090 /* available blocks on this cluster */
91 mapped_blocks = sbi->sec_per_clus - offset;
92
93 *max_blocks = min(mapped_blocks, *max_blocks);
94 MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
95
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -080096 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 if (err)
98 return err;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -070099
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800100 BUG_ON(!phys);
101 BUG_ON(*max_blocks != mapped_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 set_buffer_new(bh_result);
103 map_bh(bh_result, sb, phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800105 return 0;
106}
107
108static int fat_get_block(struct inode *inode, sector_t iblock,
109 struct buffer_head *bh_result, int create)
110{
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700111 struct super_block *sb = inode->i_sb;
112 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
113 int err;
114
115 err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create);
116 if (err)
117 return err;
118 bh_result->b_size = max_blocks << sb->s_blocksize_bits;
119 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800120}
121
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122static int fat_writepage(struct page *page, struct writeback_control *wbc)
123{
124 return block_write_full_page(page, fat_get_block, wbc);
125}
126
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800127static int fat_writepages(struct address_space *mapping,
128 struct writeback_control *wbc)
129{
130 return mpage_writepages(mapping, wbc, fat_get_block);
131}
132
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133static int fat_readpage(struct file *file, struct page *page)
134{
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800135 return mpage_readpage(page, fat_get_block);
136}
137
138static int fat_readpages(struct file *file, struct address_space *mapping,
139 struct list_head *pages, unsigned nr_pages)
140{
141 return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142}
143
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000144static void fat_write_failed(struct address_space *mapping, loff_t to)
145{
146 struct inode *inode = mapping->host;
147
148 if (to > inode->i_size) {
149 truncate_pagecache(inode, to, inode->i_size);
150 fat_truncate_blocks(inode, inode->i_size);
151 }
152}
153
Nick Piggind7777a22007-10-16 01:25:08 -0700154static int fat_write_begin(struct file *file, struct address_space *mapping,
155 loff_t pos, unsigned len, unsigned flags,
156 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157{
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000158 int err;
159
Nick Piggind7777a22007-10-16 01:25:08 -0700160 *pagep = NULL;
Christoph Hellwig282dc172010-06-04 11:29:55 +0200161 err = cont_write_begin(file, mapping, pos, len, flags,
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000162 pagep, fsdata, fat_get_block,
Nick Piggind7777a22007-10-16 01:25:08 -0700163 &MSDOS_I(mapping->host)->mmu_private);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000164 if (err < 0)
165 fat_write_failed(mapping, pos + len);
166 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167}
168
Nick Piggind7777a22007-10-16 01:25:08 -0700169static int fat_write_end(struct file *file, struct address_space *mapping,
170 loff_t pos, unsigned len, unsigned copied,
171 struct page *pagep, void *fsdata)
OGAWA Hirofumief402262005-09-16 19:28:13 -0700172{
Nick Piggind7777a22007-10-16 01:25:08 -0700173 struct inode *inode = mapping->host;
174 int err;
175 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000176 if (err < len)
177 fat_write_failed(mapping, pos + len);
Nick Piggind7777a22007-10-16 01:25:08 -0700178 if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) {
OGAWA Hirofumief402262005-09-16 19:28:13 -0700179 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
180 MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
181 mark_inode_dirty(inode);
182 }
183 return err;
184}
185
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800186static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
187 const struct iovec *iov,
188 loff_t offset, unsigned long nr_segs)
189{
190 struct file *file = iocb->ki_filp;
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000191 struct address_space *mapping = file->f_mapping;
192 struct inode *inode = mapping->host;
193 ssize_t ret;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800194
195 if (rw == WRITE) {
196 /*
Nick Piggin4e02ed42008-10-29 14:00:55 -0700197 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800198 * so we need to update the ->mmu_private to block boundary.
199 *
200 * But we must fill the remaining area or hole by nul for
201 * updating ->mmu_private.
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800202 *
203 * Return 0, and fallback to normal buffered write.
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800204 */
205 loff_t size = offset + iov_length(iov, nr_segs);
206 if (MSDOS_I(inode)->mmu_private < size)
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800207 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800208 }
209
210 /*
211 * FAT need to use the DIO_LOCKING for avoiding the race
212 * condition of fat_get_block() and ->truncate().
213 */
Christoph Hellwigaacfc19c2011-06-24 14:29:47 -0400214 ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
215 fat_get_block);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000216 if (ret < 0 && (rw & WRITE))
217 fat_write_failed(mapping, offset + iov_length(iov, nr_segs));
218
219 return ret;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800220}
221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
223{
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800224 sector_t blocknr;
225
226 /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
Christoph Hellwig58268692011-06-24 14:29:40 -0400227 down_read(&MSDOS_I(mapping->host)->truncate_lock);
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800228 blocknr = generic_block_bmap(mapping, block, fat_get_block);
Christoph Hellwig58268692011-06-24 14:29:40 -0400229 up_read(&MSDOS_I(mapping->host)->truncate_lock);
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800230
231 return blocknr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232}
233
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700234static const struct address_space_operations fat_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 .readpage = fat_readpage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800236 .readpages = fat_readpages,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 .writepage = fat_writepage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800238 .writepages = fat_writepages,
Nick Piggind7777a22007-10-16 01:25:08 -0700239 .write_begin = fat_write_begin,
240 .write_end = fat_write_end,
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800241 .direct_IO = fat_direct_IO,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 .bmap = _fat_bmap
243};
244
245/*
246 * New FAT inode stuff. We do the following:
247 * a) i_ino is constant and has nothing with on-disk location.
248 * b) FAT manages its own cache of directory entries.
249 * c) *This* cache is indexed by on-disk location.
250 * d) inode has an associated directory entry, all right, but
251 * it may be unhashed.
252 * e) currently entries are stored within struct inode. That should
253 * change.
254 * f) we deal with races in the following way:
255 * 1. readdir() and lookup() do FAT-dir-cache lookup.
256 * 2. rename() unhashes the F-d-c entry and rehashes it in
257 * a new place.
258 * 3. unlink() and rmdir() unhash F-d-c entry.
259 * 4. fat_write_inode() checks whether the thing is unhashed.
260 * If it is we silently return. If it isn't we do bread(),
261 * check if the location is still valid and retry if it
262 * isn't. Otherwise we do changes.
263 * 5. Spinlock is used to protect hash/unhash/location check/lookup
Al Virodeee3ce2010-06-05 19:28:32 -0400264 * 6. fat_evict_inode() unhashes the F-d-c entry.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
266 * and consider negative result as cache miss.
267 */
268
269static void fat_hash_init(struct super_block *sb)
270{
271 struct msdos_sb_info *sbi = MSDOS_SB(sb);
272 int i;
273
274 spin_lock_init(&sbi->inode_hash_lock);
275 for (i = 0; i < FAT_HASH_SIZE; i++)
276 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
277}
278
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800279static inline unsigned long fat_hash(loff_t i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800281 return hash_32(i_pos, FAT_HASH_BITS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282}
283
284void fat_attach(struct inode *inode, loff_t i_pos)
285{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800286 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
287 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
289 spin_lock(&sbi->inode_hash_lock);
290 MSDOS_I(inode)->i_pos = i_pos;
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800291 hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 spin_unlock(&sbi->inode_hash_lock);
293}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800294EXPORT_SYMBOL_GPL(fat_attach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
296void fat_detach(struct inode *inode)
297{
298 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
299 spin_lock(&sbi->inode_hash_lock);
300 MSDOS_I(inode)->i_pos = 0;
301 hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
302 spin_unlock(&sbi->inode_hash_lock);
303}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800304EXPORT_SYMBOL_GPL(fat_detach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
306struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
307{
308 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800309 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 struct hlist_node *_p;
311 struct msdos_inode_info *i;
312 struct inode *inode = NULL;
313
314 spin_lock(&sbi->inode_hash_lock);
315 hlist_for_each_entry(i, _p, head, i_fat_hash) {
316 BUG_ON(i->vfs_inode.i_sb != sb);
317 if (i->i_pos != i_pos)
318 continue;
319 inode = igrab(&i->vfs_inode);
320 if (inode)
321 break;
322 }
323 spin_unlock(&sbi->inode_hash_lock);
324 return inode;
325}
326
327static int is_exec(unsigned char *extension)
328{
329 unsigned char *exe_extensions = "EXECOMBAT", *walk;
330
331 for (walk = exe_extensions; *walk; walk += 3)
332 if (!strncmp(extension, walk, 3))
333 return 1;
334 return 0;
335}
336
337static int fat_calc_dir_size(struct inode *inode)
338{
339 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
340 int ret, fclus, dclus;
341
342 inode->i_size = 0;
343 if (MSDOS_I(inode)->i_start == 0)
344 return 0;
345
346 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
347 if (ret < 0)
348 return ret;
349 inode->i_size = (fclus + 1) << sbi->cluster_bits;
350
351 return 0;
352}
353
354/* doesn't deal with root inode */
355static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
356{
357 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
358 int error;
359
360 MSDOS_I(inode)->i_pos = 0;
361 inode->i_uid = sbi->options.fs_uid;
362 inode->i_gid = sbi->options.fs_gid;
363 inode->i_version++;
364 inode->i_generation = get_seconds();
365
366 if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
367 inode->i_generation &= ~1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800368 inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 inode->i_op = sbi->dir_ops;
370 inode->i_fop = &fat_dir_operations;
371
372 MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
373 if (sbi->fat_bits == 32)
374 MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
375
376 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
377 error = fat_calc_dir_size(inode);
378 if (error < 0)
379 return error;
380 MSDOS_I(inode)->mmu_private = inode->i_size;
381
382 inode->i_nlink = fat_subdirs(inode);
383 } else { /* not a directory */
384 inode->i_generation |= 1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800385 inode->i_mode = fat_make_mode(sbi, de->attr,
386 ((sbi->options.showexec && !is_exec(de->name + 8))
387 ? S_IRUGO|S_IWUGO : S_IRWXUGO));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
389 if (sbi->fat_bits == 32)
390 MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
391
392 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
393 inode->i_size = le32_to_cpu(de->size);
394 inode->i_op = &fat_file_inode_operations;
395 inode->i_fop = &fat_file_operations;
396 inode->i_mapping->a_ops = &fat_aops;
397 MSDOS_I(inode)->mmu_private = inode->i_size;
398 }
399 if (de->attr & ATTR_SYS) {
400 if (sbi->options.sys_immutable)
401 inode->i_flags |= S_IMMUTABLE;
402 }
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800403 fat_save_attrs(inode, de->attr);
404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
406 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800407
408 fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 if (sbi->options.isvfat) {
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800410 fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
411 de->cdate, de->ctime_cs);
412 fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 } else
Stephane Kardas62a36c42005-09-21 09:55:45 -0700414 inode->i_ctime = inode->i_atime = inode->i_mtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415
416 return 0;
417}
418
419struct inode *fat_build_inode(struct super_block *sb,
420 struct msdos_dir_entry *de, loff_t i_pos)
421{
422 struct inode *inode;
423 int err;
424
425 inode = fat_iget(sb, i_pos);
426 if (inode)
427 goto out;
428 inode = new_inode(sb);
429 if (!inode) {
430 inode = ERR_PTR(-ENOMEM);
431 goto out;
432 }
433 inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
434 inode->i_version = 1;
435 err = fat_fill_inode(inode, de);
436 if (err) {
437 iput(inode);
438 inode = ERR_PTR(err);
439 goto out;
440 }
441 fat_attach(inode, i_pos);
442 insert_inode_hash(inode);
443out:
444 return inode;
445}
446
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800447EXPORT_SYMBOL_GPL(fat_build_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
Al Virodeee3ce2010-06-05 19:28:32 -0400449static void fat_evict_inode(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450{
Mark Fashehfef26652005-09-09 13:01:31 -0700451 truncate_inode_pages(&inode->i_data, 0);
Al Virodeee3ce2010-06-05 19:28:32 -0400452 if (!inode->i_nlink) {
453 inode->i_size = 0;
454 fat_truncate_blocks(inode, 0);
455 }
456 invalidate_inode_buffers(inode);
457 end_writeback(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 fat_cache_inval_inode(inode);
OGAWA Hirofumia993b542008-11-06 12:53:50 -0800459 fat_detach(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460}
461
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800462static void fat_write_super(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463{
Christoph Hellwigebc1ac12009-05-11 23:35:03 +0200464 lock_super(sb);
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800465 sb->s_dirt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466
467 if (!(sb->s_flags & MS_RDONLY))
468 fat_clusters_flush(sb);
Christoph Hellwigebc1ac12009-05-11 23:35:03 +0200469 unlock_super(sb);
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800470}
471
Christoph Hellwigf83d6d42009-06-08 10:04:35 +0200472static int fat_sync_fs(struct super_block *sb, int wait)
473{
OGAWA Hirofumied248b22009-09-20 01:31:58 +0900474 int err = 0;
Christoph Hellwigf83d6d42009-06-08 10:04:35 +0200475
OGAWA Hirofumied248b22009-09-20 01:31:58 +0900476 if (sb->s_dirt) {
477 lock_super(sb);
478 sb->s_dirt = 0;
479 err = fat_clusters_flush(sb);
480 unlock_super(sb);
481 }
482
483 return err;
Christoph Hellwigf83d6d42009-06-08 10:04:35 +0200484}
485
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800486static void fat_put_super(struct super_block *sb)
487{
488 struct msdos_sb_info *sbi = MSDOS_SB(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489
Christoph Hellwig8c85e122009-04-28 18:00:26 +0200490 if (sb->s_dirt)
491 fat_write_super(sb);
492
Al Virob5224122009-06-07 13:44:36 -0400493 iput(sbi->fat_inode);
494
Thomas Gleixner6d729e42009-08-16 21:05:08 +0000495 unload_nls(sbi->nls_disk);
496 unload_nls(sbi->nls_io);
497
498 if (sbi->options.iocharset != fat_default_iocharset)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 kfree(sbi->options.iocharset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500
501 sb->s_fs_info = NULL;
502 kfree(sbi);
503}
504
Christoph Lametere18b8902006-12-06 20:33:20 -0800505static struct kmem_cache *fat_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506
507static struct inode *fat_alloc_inode(struct super_block *sb)
508{
509 struct msdos_inode_info *ei;
Linus Torvalds8f593422008-05-19 19:53:01 -0700510 ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 if (!ei)
512 return NULL;
Christoph Hellwig58268692011-06-24 14:29:40 -0400513
514 init_rwsem(&ei->truncate_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 return &ei->vfs_inode;
516}
517
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +1100518static void fat_i_callback(struct rcu_head *head)
519{
520 struct inode *inode = container_of(head, struct inode, i_rcu);
521 INIT_LIST_HEAD(&inode->i_dentry);
522 kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
523}
524
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525static void fat_destroy_inode(struct inode *inode)
526{
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +1100527 call_rcu(&inode->i_rcu, fat_i_callback);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528}
529
Alexey Dobriyan51cc5062008-07-25 19:45:34 -0700530static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531{
532 struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
533
Christoph Lametera35afb82007-05-16 22:10:57 -0700534 spin_lock_init(&ei->cache_lru_lock);
535 ei->nr_caches = 0;
536 ei->cache_valid_id = FAT_CACHE_VALID + 1;
537 INIT_LIST_HEAD(&ei->cache_lru);
538 INIT_HLIST_NODE(&ei->i_fat_hash);
539 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540}
541
542static int __init fat_init_inodecache(void)
543{
544 fat_inode_cachep = kmem_cache_create("fat_inode_cache",
545 sizeof(struct msdos_inode_info),
Paul Jacksonfffb60f2006-03-24 03:16:06 -0800546 0, (SLAB_RECLAIM_ACCOUNT|
547 SLAB_MEM_SPREAD),
Paul Mundt20c2df82007-07-20 10:11:58 +0900548 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 if (fat_inode_cachep == NULL)
550 return -ENOMEM;
551 return 0;
552}
553
554static void __exit fat_destroy_inodecache(void)
555{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -0700556 kmem_cache_destroy(fat_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557}
558
559static int fat_remount(struct super_block *sb, int *flags, char *data)
560{
561 struct msdos_sb_info *sbi = MSDOS_SB(sb);
562 *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
563 return 0;
564}
565
David Howells726c3342006-06-23 02:02:58 -0700566static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567{
Coly Liaac49b72009-04-02 16:59:35 -0700568 struct super_block *sb = dentry->d_sb;
569 struct msdos_sb_info *sbi = MSDOS_SB(sb);
570 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571
572 /* If the count of free cluster is still unknown, counts it here. */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -0700573 if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
David Howells726c3342006-06-23 02:02:58 -0700574 int err = fat_count_free_clusters(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 if (err)
576 return err;
577 }
578
David Howells726c3342006-06-23 02:02:58 -0700579 buf->f_type = dentry->d_sb->s_magic;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 buf->f_bsize = sbi->cluster_size;
581 buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
582 buf->f_bfree = sbi->free_clusters;
583 buf->f_bavail = sbi->free_clusters;
Coly Liaac49b72009-04-02 16:59:35 -0700584 buf->f_fsid.val[0] = (u32)id;
585 buf->f_fsid.val[1] = (u32)(id >> 32);
OGAWA Hirofumif68e5422011-04-12 21:08:39 +0900586 buf->f_namelen =
587 (sbi->options.isvfat ? FAT_LFN_LEN : 12) * NLS_MAX_CHARSET_SIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588
589 return 0;
590}
591
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800592static inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi,
593 struct inode *inode)
594{
595 loff_t i_pos;
596#if BITS_PER_LONG == 32
597 spin_lock(&sbi->inode_hash_lock);
598#endif
599 i_pos = MSDOS_I(inode)->i_pos;
600#if BITS_PER_LONG == 32
601 spin_unlock(&sbi->inode_hash_lock);
602#endif
603 return i_pos;
604}
605
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100606static int __fat_write_inode(struct inode *inode, int wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607{
608 struct super_block *sb = inode->i_sb;
609 struct msdos_sb_info *sbi = MSDOS_SB(sb);
610 struct buffer_head *bh;
611 struct msdos_dir_entry *raw_entry;
612 loff_t i_pos;
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700613 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800615 if (inode->i_ino == MSDOS_ROOT_INO)
616 return 0;
617
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618retry:
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800619 i_pos = fat_i_pos_read(sbi, inode);
620 if (!i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 return 0;
622
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits);
624 if (!bh) {
Alexey Fisher869f58c2011-04-12 21:08:38 +0900625 fat_msg(sb, KERN_ERR, "unable to read inode block "
626 "for updating (i_pos %lld)", i_pos);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700627 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 }
629 spin_lock(&sbi->inode_hash_lock);
630 if (i_pos != MSDOS_I(inode)->i_pos) {
631 spin_unlock(&sbi->inode_hash_lock);
632 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 goto retry;
634 }
635
636 raw_entry = &((struct msdos_dir_entry *) (bh->b_data))
637 [i_pos & (sbi->dir_per_block - 1)];
638 if (S_ISDIR(inode->i_mode))
639 raw_entry->size = 0;
640 else
641 raw_entry->size = cpu_to_le32(inode->i_size);
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800642 raw_entry->attr = fat_make_attrs(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
644 raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800645 fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
646 &raw_entry->date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 if (sbi->options.isvfat) {
Stephane Kardas62a36c42005-09-21 09:55:45 -0700648 __le16 atime;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800649 fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
650 &raw_entry->cdate, &raw_entry->ctime_cs);
651 fat_time_unix2fat(sbi, &inode->i_atime, &atime,
652 &raw_entry->adate, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 }
654 spin_unlock(&sbi->inode_hash_lock);
655 mark_buffer_dirty(bh);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700656 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 if (wait)
658 err = sync_dirty_buffer(bh);
659 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 return err;
661}
662
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100663static int fat_write_inode(struct inode *inode, struct writeback_control *wbc)
664{
665 return __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
666}
667
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668int fat_sync_inode(struct inode *inode)
669{
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100670 return __fat_write_inode(inode, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671}
672
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800673EXPORT_SYMBOL_GPL(fat_sync_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674
675static int fat_show_options(struct seq_file *m, struct vfsmount *mnt);
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800676static const struct super_operations fat_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 .alloc_inode = fat_alloc_inode,
678 .destroy_inode = fat_destroy_inode,
679 .write_inode = fat_write_inode,
Al Virodeee3ce2010-06-05 19:28:32 -0400680 .evict_inode = fat_evict_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681 .put_super = fat_put_super,
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800682 .write_super = fat_write_super,
Christoph Hellwigf83d6d42009-06-08 10:04:35 +0200683 .sync_fs = fat_sync_fs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 .statfs = fat_statfs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685 .remount_fs = fat_remount,
686
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 .show_options = fat_show_options,
688};
689
690/*
691 * a FAT file handle with fhtype 3 is
692 * 0/ i_ino - for fast, reliable lookup if still in the cache
693 * 1/ i_generation - to see if i_ino is still valid
694 * bit 0 == 0 iff directory
695 * 2/ i_pos(8-39) - if ino has changed, but still in cache
696 * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos
697 * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc
698 *
699 * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum
700 * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits
701 * of i_logstart is used to store the directory entry offset.
702 */
703
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700704static struct dentry *fat_fh_to_dentry(struct super_block *sb,
705 struct fid *fid, int fh_len, int fh_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706{
707 struct inode *inode = NULL;
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700708 u32 *fh = fid->raw;
709
710 if (fh_len < 5 || fh_type != 3)
711 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712
David Howells17f95a72008-02-07 00:15:38 -0800713 inode = ilookup(sb, fh[0]);
714 if (!inode || inode->i_generation != fh[1]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 if (inode)
716 iput(inode);
717 inode = NULL;
718 }
719 if (!inode) {
720 loff_t i_pos;
721 int i_logstart = fh[3] & 0x0fffffff;
722
723 i_pos = (loff_t)fh[2] << 8;
724 i_pos |= ((fh[3] >> 24) & 0xf0) | (fh[4] >> 28);
725
726 /* try 2 - see if i_pos is in F-d-c
727 * require i_logstart to be the same
728 * Will fail if you truncate and then re-write
729 */
730
731 inode = fat_iget(sb, i_pos);
732 if (inode && MSDOS_I(inode)->i_logstart != i_logstart) {
733 iput(inode);
734 inode = NULL;
735 }
736 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737
Christoph Hellwig44003722008-08-11 15:49:04 +0200738 /*
739 * For now, do nothing if the inode is not found.
740 *
741 * What we could do is:
742 *
743 * - follow the file starting at fh[4], and record the ".." entry,
744 * and the name of the fh[2] entry.
745 * - then follow the ".." file finding the next step up.
746 *
747 * This way we build a path to the root of the tree. If this works, we
748 * lookup the path and so get this inode into the cache. Finally try
749 * the fat_iget lookup again. If that fails, then we are totally out
750 * of luck. But all that is for another day
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751 */
Al Viro3d239852010-12-18 10:44:00 -0500752 return d_obtain_alias(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753}
754
755static int
756fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable)
757{
758 int len = *lenp;
759 struct inode *inode = de->d_inode;
760 u32 ipos_h, ipos_m, ipos_l;
761
Aneesh Kumar K.V5fe0c232011-01-29 18:43:25 +0530762 if (len < 5) {
763 *lenp = 5;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 return 255; /* no room */
Aneesh Kumar K.V5fe0c232011-01-29 18:43:25 +0530765 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766
767 ipos_h = MSDOS_I(inode)->i_pos >> 8;
768 ipos_m = (MSDOS_I(inode)->i_pos & 0xf0) << 24;
769 ipos_l = (MSDOS_I(inode)->i_pos & 0x0f) << 28;
770 *lenp = 5;
771 fh[0] = inode->i_ino;
772 fh[1] = inode->i_generation;
773 fh[2] = ipos_h;
774 fh[3] = ipos_m | MSDOS_I(inode)->i_logstart;
775 spin_lock(&de->d_lock);
776 fh[4] = ipos_l | MSDOS_I(de->d_parent->d_inode)->i_logstart;
777 spin_unlock(&de->d_lock);
778 return 3;
779}
780
781static struct dentry *fat_get_parent(struct dentry *child)
782{
Linus Torvalds8f593422008-05-19 19:53:01 -0700783 struct super_block *sb = child->d_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 struct buffer_head *bh;
785 struct msdos_dir_entry *de;
786 loff_t i_pos;
787 struct dentry *parent;
788 struct inode *inode;
789 int err;
790
Linus Torvalds8f593422008-05-19 19:53:01 -0700791 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792
793 err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos);
794 if (err) {
795 parent = ERR_PTR(err);
796 goto out;
797 }
Linus Torvalds8f593422008-05-19 19:53:01 -0700798 inode = fat_build_inode(sb, de, i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 brelse(bh);
Christoph Hellwig44003722008-08-11 15:49:04 +0200800
801 parent = d_obtain_alias(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700803 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
805 return parent;
806}
807
Christoph Hellwig39655162007-10-21 16:42:17 -0700808static const struct export_operations fat_export_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 .encode_fh = fat_encode_fh,
Christoph Hellwig1305edad2007-10-21 16:42:11 -0700810 .fh_to_dentry = fat_fh_to_dentry,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811 .get_parent = fat_get_parent,
812};
813
814static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
815{
816 struct msdos_sb_info *sbi = MSDOS_SB(mnt->mnt_sb);
817 struct fat_mount_options *opts = &sbi->options;
818 int isvfat = opts->isvfat;
819
820 if (opts->fs_uid != 0)
821 seq_printf(m, ",uid=%u", opts->fs_uid);
822 if (opts->fs_gid != 0)
823 seq_printf(m, ",gid=%u", opts->fs_gid);
824 seq_printf(m, ",fmask=%04o", opts->fs_fmask);
825 seq_printf(m, ",dmask=%04o", opts->fs_dmask);
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700826 if (opts->allow_utime)
827 seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 if (sbi->nls_disk)
829 seq_printf(m, ",codepage=%s", sbi->nls_disk->charset);
830 if (isvfat) {
831 if (sbi->nls_io)
832 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
833
834 switch (opts->shortname) {
835 case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
836 seq_puts(m, ",shortname=win95");
837 break;
838 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
839 seq_puts(m, ",shortname=winnt");
840 break;
841 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
842 seq_puts(m, ",shortname=mixed");
843 break;
844 case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
Paul Wise95523472009-08-01 21:30:31 +0900845 seq_puts(m, ",shortname=lower");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 break;
847 default:
848 seq_puts(m, ",shortname=unknown");
849 break;
850 }
851 }
852 if (opts->name_check != 'n')
853 seq_printf(m, ",check=%c", opts->name_check);
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700854 if (opts->usefree)
855 seq_puts(m, ",usefree");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 if (opts->quiet)
857 seq_puts(m, ",quiet");
858 if (opts->showexec)
859 seq_puts(m, ",showexec");
860 if (opts->sys_immutable)
861 seq_puts(m, ",sys_immutable");
862 if (!isvfat) {
863 if (opts->dotsOK)
864 seq_puts(m, ",dotsOK=yes");
865 if (opts->nocase)
866 seq_puts(m, ",nocase");
867 } else {
868 if (opts->utf8)
869 seq_puts(m, ",utf8");
870 if (opts->unicode_xlate)
871 seq_puts(m, ",uni_xlate");
872 if (!opts->numtail)
873 seq_puts(m, ",nonumtail");
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800874 if (opts->rodir)
875 seq_puts(m, ",rodir");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 }
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800877 if (opts->flush)
Miklos Szeredic1fca3b2008-02-08 04:21:42 -0800878 seq_puts(m, ",flush");
Joe Petersonb271e062008-07-25 01:46:47 -0700879 if (opts->tz_utc)
880 seq_puts(m, ",tz=UTC");
Denis Karpov85c78592009-06-04 02:34:22 +0900881 if (opts->errors == FAT_ERRORS_CONT)
882 seq_puts(m, ",errors=continue");
883 else if (opts->errors == FAT_ERRORS_PANIC)
884 seq_puts(m, ",errors=panic");
885 else
886 seq_puts(m, ",errors=remount-ro");
Christoph Hellwig681142f2009-11-21 20:28:52 +0900887 if (opts->discard)
888 seq_puts(m, ",discard");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889
890 return 0;
891}
892
893enum {
894 Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700895 Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage,
896 Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug,
897 Opt_immutable, Opt_dots, Opt_nodots,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898 Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
899 Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
900 Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
Denis Karpov85c78592009-06-04 02:34:22 +0900901 Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont,
Christoph Hellwig681142f2009-11-21 20:28:52 +0900902 Opt_err_panic, Opt_err_ro, Opt_discard, Opt_err,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903};
904
Steven Whitehousea447c092008-10-13 10:46:57 +0100905static const match_table_t fat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 {Opt_check_r, "check=relaxed"},
907 {Opt_check_s, "check=strict"},
908 {Opt_check_n, "check=normal"},
909 {Opt_check_r, "check=r"},
910 {Opt_check_s, "check=s"},
911 {Opt_check_n, "check=n"},
912 {Opt_uid, "uid=%u"},
913 {Opt_gid, "gid=%u"},
914 {Opt_umask, "umask=%o"},
915 {Opt_dmask, "dmask=%o"},
916 {Opt_fmask, "fmask=%o"},
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700917 {Opt_allow_utime, "allow_utime=%o"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 {Opt_codepage, "codepage=%u"},
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700919 {Opt_usefree, "usefree"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 {Opt_nocase, "nocase"},
921 {Opt_quiet, "quiet"},
922 {Opt_showexec, "showexec"},
923 {Opt_debug, "debug"},
924 {Opt_immutable, "sys_immutable"},
Denis Karpov85c78592009-06-04 02:34:22 +0900925 {Opt_flush, "flush"},
926 {Opt_tz_utc, "tz=UTC"},
927 {Opt_err_cont, "errors=continue"},
928 {Opt_err_panic, "errors=panic"},
929 {Opt_err_ro, "errors=remount-ro"},
Christoph Hellwig681142f2009-11-21 20:28:52 +0900930 {Opt_discard, "discard"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 {Opt_obsolate, "conv=binary"},
932 {Opt_obsolate, "conv=text"},
933 {Opt_obsolate, "conv=auto"},
934 {Opt_obsolate, "conv=b"},
935 {Opt_obsolate, "conv=t"},
936 {Opt_obsolate, "conv=a"},
937 {Opt_obsolate, "fat=%u"},
938 {Opt_obsolate, "blocksize=%u"},
939 {Opt_obsolate, "cvf_format=%20s"},
940 {Opt_obsolate, "cvf_options=%100s"},
941 {Opt_obsolate, "posix"},
Chris Masonae78bf92006-09-29 02:00:03 -0700942 {Opt_err, NULL},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943};
Steven Whitehousea447c092008-10-13 10:46:57 +0100944static const match_table_t msdos_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 {Opt_nodots, "nodots"},
946 {Opt_nodots, "dotsOK=no"},
947 {Opt_dots, "dots"},
948 {Opt_dots, "dotsOK=yes"},
949 {Opt_err, NULL}
950};
Steven Whitehousea447c092008-10-13 10:46:57 +0100951static const match_table_t vfat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952 {Opt_charset, "iocharset=%s"},
953 {Opt_shortname_lower, "shortname=lower"},
954 {Opt_shortname_win95, "shortname=win95"},
955 {Opt_shortname_winnt, "shortname=winnt"},
956 {Opt_shortname_mixed, "shortname=mixed"},
957 {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
958 {Opt_utf8_no, "utf8=no"},
959 {Opt_utf8_no, "utf8=false"},
960 {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
961 {Opt_utf8_yes, "utf8=yes"},
962 {Opt_utf8_yes, "utf8=true"},
963 {Opt_utf8_yes, "utf8"},
964 {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
965 {Opt_uni_xl_no, "uni_xlate=no"},
966 {Opt_uni_xl_no, "uni_xlate=false"},
967 {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
968 {Opt_uni_xl_yes, "uni_xlate=yes"},
969 {Opt_uni_xl_yes, "uni_xlate=true"},
970 {Opt_uni_xl_yes, "uni_xlate"},
971 {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
972 {Opt_nonumtail_no, "nonumtail=no"},
973 {Opt_nonumtail_no, "nonumtail=false"},
974 {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
975 {Opt_nonumtail_yes, "nonumtail=yes"},
976 {Opt_nonumtail_yes, "nonumtail=true"},
977 {Opt_nonumtail_yes, "nonumtail"},
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800978 {Opt_rodir, "rodir"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 {Opt_err, NULL}
980};
981
Alexey Fisher869f58c2011-04-12 21:08:38 +0900982static int parse_options(struct super_block *sb, char *options, int is_vfat,
983 int silent, int *debug, struct fat_mount_options *opts)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984{
985 char *p;
986 substring_t args[MAX_OPT_ARGS];
987 int option;
988 char *iocharset;
989
990 opts->isvfat = is_vfat;
991
David Howellsf0ce7ee2008-11-14 10:38:52 +1100992 opts->fs_uid = current_uid();
993 opts->fs_gid = current_gid();
OGAWA Hirofumi3e107602009-06-20 21:50:07 +0900994 opts->fs_fmask = opts->fs_dmask = current_umask();
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700995 opts->allow_utime = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 opts->codepage = fat_default_codepage;
997 opts->iocharset = fat_default_iocharset;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800998 if (is_vfat) {
Paul Wise95523472009-08-01 21:30:31 +0900999 opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001000 opts->rodir = 0;
1001 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 opts->shortname = 0;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001003 opts->rodir = 1;
1004 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005 opts->name_check = 'n';
1006 opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
1007 opts->utf8 = opts->unicode_xlate = 0;
1008 opts->numtail = 1;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001009 opts->usefree = opts->nocase = 0;
Joe Petersonb271e062008-07-25 01:46:47 -07001010 opts->tz_utc = 0;
Denis Karpov85c78592009-06-04 02:34:22 +09001011 opts->errors = FAT_ERRORS_RO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 *debug = 0;
1013
1014 if (!options)
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001015 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016
1017 while ((p = strsep(&options, ",")) != NULL) {
1018 int token;
1019 if (!*p)
1020 continue;
1021
1022 token = match_token(p, fat_tokens, args);
1023 if (token == Opt_err) {
1024 if (is_vfat)
1025 token = match_token(p, vfat_tokens, args);
1026 else
1027 token = match_token(p, msdos_tokens, args);
1028 }
1029 switch (token) {
1030 case Opt_check_s:
1031 opts->name_check = 's';
1032 break;
1033 case Opt_check_r:
1034 opts->name_check = 'r';
1035 break;
1036 case Opt_check_n:
1037 opts->name_check = 'n';
1038 break;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001039 case Opt_usefree:
1040 opts->usefree = 1;
1041 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042 case Opt_nocase:
1043 if (!is_vfat)
1044 opts->nocase = 1;
1045 else {
1046 /* for backward compatibility */
1047 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1048 | VFAT_SFN_CREATE_WIN95;
1049 }
1050 break;
1051 case Opt_quiet:
1052 opts->quiet = 1;
1053 break;
1054 case Opt_showexec:
1055 opts->showexec = 1;
1056 break;
1057 case Opt_debug:
1058 *debug = 1;
1059 break;
1060 case Opt_immutable:
1061 opts->sys_immutable = 1;
1062 break;
1063 case Opt_uid:
1064 if (match_int(&args[0], &option))
1065 return 0;
1066 opts->fs_uid = option;
1067 break;
1068 case Opt_gid:
1069 if (match_int(&args[0], &option))
1070 return 0;
1071 opts->fs_gid = option;
1072 break;
1073 case Opt_umask:
1074 if (match_octal(&args[0], &option))
1075 return 0;
1076 opts->fs_fmask = opts->fs_dmask = option;
1077 break;
1078 case Opt_dmask:
1079 if (match_octal(&args[0], &option))
1080 return 0;
1081 opts->fs_dmask = option;
1082 break;
1083 case Opt_fmask:
1084 if (match_octal(&args[0], &option))
1085 return 0;
1086 opts->fs_fmask = option;
1087 break;
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001088 case Opt_allow_utime:
1089 if (match_octal(&args[0], &option))
1090 return 0;
1091 opts->allow_utime = option & (S_IWGRP | S_IWOTH);
1092 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093 case Opt_codepage:
1094 if (match_int(&args[0], &option))
1095 return 0;
1096 opts->codepage = option;
1097 break;
Chris Masonae78bf92006-09-29 02:00:03 -07001098 case Opt_flush:
1099 opts->flush = 1;
1100 break;
Joe Petersonb271e062008-07-25 01:46:47 -07001101 case Opt_tz_utc:
1102 opts->tz_utc = 1;
1103 break;
Denis Karpov85c78592009-06-04 02:34:22 +09001104 case Opt_err_cont:
1105 opts->errors = FAT_ERRORS_CONT;
1106 break;
1107 case Opt_err_panic:
1108 opts->errors = FAT_ERRORS_PANIC;
1109 break;
1110 case Opt_err_ro:
1111 opts->errors = FAT_ERRORS_RO;
1112 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113
1114 /* msdos specific */
1115 case Opt_dots:
1116 opts->dotsOK = 1;
1117 break;
1118 case Opt_nodots:
1119 opts->dotsOK = 0;
1120 break;
1121
1122 /* vfat specific */
1123 case Opt_charset:
1124 if (opts->iocharset != fat_default_iocharset)
1125 kfree(opts->iocharset);
1126 iocharset = match_strdup(&args[0]);
1127 if (!iocharset)
1128 return -ENOMEM;
1129 opts->iocharset = iocharset;
1130 break;
1131 case Opt_shortname_lower:
1132 opts->shortname = VFAT_SFN_DISPLAY_LOWER
1133 | VFAT_SFN_CREATE_WIN95;
1134 break;
1135 case Opt_shortname_win95:
1136 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1137 | VFAT_SFN_CREATE_WIN95;
1138 break;
1139 case Opt_shortname_winnt:
1140 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1141 | VFAT_SFN_CREATE_WINNT;
1142 break;
1143 case Opt_shortname_mixed:
1144 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1145 | VFAT_SFN_CREATE_WIN95;
1146 break;
1147 case Opt_utf8_no: /* 0 or no or false */
1148 opts->utf8 = 0;
1149 break;
1150 case Opt_utf8_yes: /* empty or 1 or yes or true */
1151 opts->utf8 = 1;
1152 break;
1153 case Opt_uni_xl_no: /* 0 or no or false */
1154 opts->unicode_xlate = 0;
1155 break;
1156 case Opt_uni_xl_yes: /* empty or 1 or yes or true */
1157 opts->unicode_xlate = 1;
1158 break;
1159 case Opt_nonumtail_no: /* 0 or no or false */
1160 opts->numtail = 1; /* negated option */
1161 break;
1162 case Opt_nonumtail_yes: /* empty or 1 or yes or true */
1163 opts->numtail = 0; /* negated option */
1164 break;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001165 case Opt_rodir:
1166 opts->rodir = 1;
1167 break;
Christoph Hellwig681142f2009-11-21 20:28:52 +09001168 case Opt_discard:
1169 opts->discard = 1;
1170 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171
1172 /* obsolete mount options */
1173 case Opt_obsolate:
Alexey Fisher869f58c2011-04-12 21:08:38 +09001174 fat_msg(sb, KERN_INFO, "\"%s\" option is obsolete, "
1175 "not supported now", p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176 break;
1177 /* unknown option */
1178 default:
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001179 if (!silent) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001180 fat_msg(sb, KERN_ERR,
1181 "Unrecognized mount option \"%s\" "
1182 "or missing value", p);
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001183 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184 return -EINVAL;
1185 }
1186 }
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001187
1188out:
Alexey Dobriyan4de151d2006-03-22 00:13:35 +01001189 /* UTF-8 doesn't provide FAT semantics */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001190 if (!strcmp(opts->iocharset, "utf8")) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001191 fat_msg(sb, KERN_ERR, "utf8 is not a recommended IO charset"
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001192 " for FAT filesystems, filesystem will be "
1193 "case sensitive!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001194 }
1195
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001196 /* If user doesn't specify allow_utime, it's initialized from dmask. */
1197 if (opts->allow_utime == (unsigned short)-1)
1198 opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199 if (opts->unicode_xlate)
1200 opts->utf8 = 0;
1201
1202 return 0;
1203}
1204
1205static int fat_read_root(struct inode *inode)
1206{
1207 struct super_block *sb = inode->i_sb;
1208 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1209 int error;
1210
1211 MSDOS_I(inode)->i_pos = 0;
1212 inode->i_uid = sbi->options.fs_uid;
1213 inode->i_gid = sbi->options.fs_gid;
1214 inode->i_version++;
1215 inode->i_generation = 0;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001216 inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001217 inode->i_op = sbi->dir_ops;
1218 inode->i_fop = &fat_dir_operations;
1219 if (sbi->fat_bits == 32) {
1220 MSDOS_I(inode)->i_start = sbi->root_cluster;
1221 error = fat_calc_dir_size(inode);
1222 if (error < 0)
1223 return error;
1224 } else {
1225 MSDOS_I(inode)->i_start = 0;
1226 inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
1227 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
1229 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
1230 MSDOS_I(inode)->i_logstart = 0;
1231 MSDOS_I(inode)->mmu_private = inode->i_size;
1232
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001233 fat_save_attrs(inode, ATTR_DIR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
1235 inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
1236 inode->i_nlink = fat_subdirs(inode)+2;
1237
1238 return 0;
1239}
1240
1241/*
1242 * Read the super block of an MS-DOS FS.
1243 */
OGAWA Hirofumi384f5c92011-04-12 21:08:37 +09001244int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
Al Viro3d239852010-12-18 10:44:00 -05001245 void (*setup)(struct super_block *))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001246{
Al Virob5224122009-06-07 13:44:36 -04001247 struct inode *root_inode = NULL, *fat_inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248 struct buffer_head *bh;
1249 struct fat_boot_sector *b;
1250 struct msdos_sb_info *sbi;
1251 u16 logical_sector_size;
1252 u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
1253 int debug;
1254 unsigned int media;
1255 long error;
1256 char buf[50];
1257
Linus Torvalds8f593422008-05-19 19:53:01 -07001258 /*
1259 * GFP_KERNEL is ok here, because while we do hold the
1260 * supeblock lock, memory pressure can't call back into
1261 * the filesystem, since we're only just about to mount
1262 * it and have no inodes etc active!
1263 */
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -07001264 sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265 if (!sbi)
1266 return -ENOMEM;
1267 sb->s_fs_info = sbi;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268
1269 sb->s_flags |= MS_NODIRATIME;
1270 sb->s_magic = MSDOS_SUPER_MAGIC;
1271 sb->s_op = &fat_sops;
1272 sb->s_export_op = &fat_export_ops;
OGAWA Hirofumiaaa04b42010-05-24 14:33:12 -07001273 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
1274 DEFAULT_RATELIMIT_BURST);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275
Alexey Fisher869f58c2011-04-12 21:08:38 +09001276 error = parse_options(sb, data, isvfat, silent, &debug, &sbi->options);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 if (error)
1278 goto out_fail;
1279
Al Viro3d239852010-12-18 10:44:00 -05001280 setup(sb); /* flavour-specific stuff that needs options */
1281
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282 error = -EIO;
1283 sb_min_blocksize(sb, 512);
1284 bh = sb_bread(sb, 0);
1285 if (bh == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001286 fat_msg(sb, KERN_ERR, "unable to read boot sector");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287 goto out_fail;
1288 }
1289
1290 b = (struct fat_boot_sector *) bh->b_data;
1291 if (!b->reserved) {
1292 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001293 fat_msg(sb, KERN_ERR, "bogus number of reserved sectors");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294 brelse(bh);
1295 goto out_invalid;
1296 }
1297 if (!b->fats) {
1298 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001299 fat_msg(sb, KERN_ERR, "bogus number of FAT structure");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300 brelse(bh);
1301 goto out_invalid;
1302 }
1303
1304 /*
1305 * Earlier we checked here that b->secs_track and b->head are nonzero,
1306 * but it turns out valid FAT filesystems can have zero there.
1307 */
1308
1309 media = b->media;
Andrew Morton73f20e52008-04-28 02:16:30 -07001310 if (!fat_valid_media(media)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001312 fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001313 media);
1314 brelse(bh);
1315 goto out_invalid;
1316 }
Harvey Harrison803f4452008-04-29 01:03:43 -07001317 logical_sector_size = get_unaligned_le16(&b->sector_size);
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -07001318 if (!is_power_of_2(logical_sector_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319 || (logical_sector_size < 512)
Olof Johansson9f354852008-04-28 02:16:32 -07001320 || (logical_sector_size > 4096)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001322 fat_msg(sb, KERN_ERR, "bogus logical sector size %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 logical_sector_size);
1324 brelse(bh);
1325 goto out_invalid;
1326 }
1327 sbi->sec_per_clus = b->sec_per_clus;
Vignesh Babu BMe7d709c2007-05-08 00:24:27 -07001328 if (!is_power_of_2(sbi->sec_per_clus)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001330 fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 sbi->sec_per_clus);
1332 brelse(bh);
1333 goto out_invalid;
1334 }
1335
1336 if (logical_sector_size < sb->s_blocksize) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001337 fat_msg(sb, KERN_ERR, "logical sector size too small for device"
1338 " (logical sector size = %u)", logical_sector_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001339 brelse(bh);
1340 goto out_fail;
1341 }
1342 if (logical_sector_size > sb->s_blocksize) {
1343 brelse(bh);
1344
1345 if (!sb_set_blocksize(sb, logical_sector_size)) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001346 fat_msg(sb, KERN_ERR, "unable to set blocksize %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347 logical_sector_size);
1348 goto out_fail;
1349 }
1350 bh = sb_bread(sb, 0);
1351 if (bh == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001352 fat_msg(sb, KERN_ERR, "unable to read boot sector"
1353 " (logical sector size = %lu)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 sb->s_blocksize);
1355 goto out_fail;
1356 }
1357 b = (struct fat_boot_sector *) bh->b_data;
1358 }
1359
1360 sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
1361 sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
1362 sbi->fats = b->fats;
1363 sbi->fat_bits = 0; /* Don't know yet */
1364 sbi->fat_start = le16_to_cpu(b->reserved);
1365 sbi->fat_length = le16_to_cpu(b->fat_length);
1366 sbi->root_cluster = 0;
1367 sbi->free_clusters = -1; /* Don't know yet */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001368 sbi->free_clus_valid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369 sbi->prev_free = FAT_START_ENT;
1370
1371 if (!sbi->fat_length && b->fat32_length) {
1372 struct fat_boot_fsinfo *fsinfo;
1373 struct buffer_head *fsinfo_bh;
1374
1375 /* Must be FAT32 */
1376 sbi->fat_bits = 32;
1377 sbi->fat_length = le32_to_cpu(b->fat32_length);
1378 sbi->root_cluster = le32_to_cpu(b->root_cluster);
1379
1380 sb->s_maxbytes = 0xffffffff;
1381
1382 /* MC - if info_sector is 0, don't multiply by 0 */
1383 sbi->fsinfo_sector = le16_to_cpu(b->info_sector);
1384 if (sbi->fsinfo_sector == 0)
1385 sbi->fsinfo_sector = 1;
1386
1387 fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
1388 if (fsinfo_bh == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001389 fat_msg(sb, KERN_ERR, "bread failed, FSINFO block"
1390 " (sector = %lu)", sbi->fsinfo_sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001391 brelse(bh);
1392 goto out_fail;
1393 }
1394
1395 fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
1396 if (!IS_FSINFO(fsinfo)) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001397 fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: "
1398 "0x%08x, 0x%08x (sector = %lu)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001399 le32_to_cpu(fsinfo->signature1),
1400 le32_to_cpu(fsinfo->signature2),
1401 sbi->fsinfo_sector);
1402 } else {
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001403 if (sbi->options.usefree)
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001404 sbi->free_clus_valid = 1;
1405 sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
1407 }
1408
1409 brelse(fsinfo_bh);
1410 }
1411
1412 sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
1413 sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
1414
1415 sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
Harvey Harrison803f4452008-04-29 01:03:43 -07001416 sbi->dir_entries = get_unaligned_le16(&b->dir_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
1418 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001419 fat_msg(sb, KERN_ERR, "bogus directroy-entries per block"
1420 " (%u)", sbi->dir_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 brelse(bh);
1422 goto out_invalid;
1423 }
1424
1425 rootdir_sectors = sbi->dir_entries
1426 * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
1427 sbi->data_start = sbi->dir_start + rootdir_sectors;
Harvey Harrison803f4452008-04-29 01:03:43 -07001428 total_sectors = get_unaligned_le16(&b->sectors);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 if (total_sectors == 0)
1430 total_sectors = le32_to_cpu(b->total_sect);
1431
1432 total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
1433
1434 if (sbi->fat_bits != 32)
1435 sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
1436
1437 /* check that FAT table does not overflow */
1438 fat_clusters = sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
1439 total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
1440 if (total_clusters > MAX_FAT(sb)) {
1441 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001442 fat_msg(sb, KERN_ERR, "count of clusters too big (%u)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443 total_clusters);
1444 brelse(bh);
1445 goto out_invalid;
1446 }
1447
1448 sbi->max_cluster = total_clusters + FAT_START_ENT;
1449 /* check the free_clusters, it's not necessarily correct */
1450 if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
1451 sbi->free_clusters = -1;
1452 /* check the prev_free, it's not necessarily correct */
1453 sbi->prev_free %= sbi->max_cluster;
1454 if (sbi->prev_free < FAT_START_ENT)
1455 sbi->prev_free = FAT_START_ENT;
1456
1457 brelse(bh);
1458
1459 /* set up enough so that it can read an inode */
1460 fat_hash_init(sb);
1461 fat_ent_access_init(sb);
1462
1463 /*
1464 * The low byte of FAT's first entry must have same value with
1465 * media-field. But in real world, too many devices is
1466 * writing wrong value. So, removed that validity check.
1467 *
1468 * if (FAT_FIRST_ENT(sb, media) != first)
1469 */
1470
1471 error = -EINVAL;
1472 sprintf(buf, "cp%d", sbi->options.codepage);
1473 sbi->nls_disk = load_nls(buf);
1474 if (!sbi->nls_disk) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001475 fat_msg(sb, KERN_ERR, "codepage %s not found", buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 goto out_fail;
1477 }
1478
1479 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1480 if (sbi->options.isvfat) {
1481 sbi->nls_io = load_nls(sbi->options.iocharset);
1482 if (!sbi->nls_io) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001483 fat_msg(sb, KERN_ERR, "IO charset %s not found",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001484 sbi->options.iocharset);
1485 goto out_fail;
1486 }
1487 }
1488
1489 error = -ENOMEM;
Al Virob5224122009-06-07 13:44:36 -04001490 fat_inode = new_inode(sb);
1491 if (!fat_inode)
1492 goto out_fail;
1493 MSDOS_I(fat_inode)->i_pos = 0;
1494 sbi->fat_inode = fat_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 root_inode = new_inode(sb);
1496 if (!root_inode)
1497 goto out_fail;
1498 root_inode->i_ino = MSDOS_ROOT_INO;
1499 root_inode->i_version = 1;
1500 error = fat_read_root(root_inode);
1501 if (error < 0)
1502 goto out_fail;
1503 error = -ENOMEM;
1504 insert_inode_hash(root_inode);
1505 sb->s_root = d_alloc_root(root_inode);
1506 if (!sb->s_root) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001507 fat_msg(sb, KERN_ERR, "get root inode failed");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508 goto out_fail;
1509 }
1510
1511 return 0;
1512
1513out_invalid:
1514 error = -EINVAL;
1515 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001516 fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001517
1518out_fail:
Al Virob5224122009-06-07 13:44:36 -04001519 if (fat_inode)
1520 iput(fat_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521 if (root_inode)
1522 iput(root_inode);
OGAWA Hirofumi1bdb6f92010-03-16 05:48:09 +09001523 unload_nls(sbi->nls_io);
1524 unload_nls(sbi->nls_disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525 if (sbi->options.iocharset != fat_default_iocharset)
1526 kfree(sbi->options.iocharset);
1527 sb->s_fs_info = NULL;
1528 kfree(sbi);
1529 return error;
1530}
1531
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -08001532EXPORT_SYMBOL_GPL(fat_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001533
Chris Masonae78bf92006-09-29 02:00:03 -07001534/*
1535 * helper function for fat_flush_inodes. This writes both the inode
1536 * and the file data blocks, waiting for in flight data blocks before
1537 * the start of the call. It does not wait for any io started
1538 * during the call
1539 */
1540static int writeback_inode(struct inode *inode)
1541{
1542
1543 int ret;
1544 struct address_space *mapping = inode->i_mapping;
1545 struct writeback_control wbc = {
1546 .sync_mode = WB_SYNC_NONE,
1547 .nr_to_write = 0,
1548 };
1549 /* if we used WB_SYNC_ALL, sync_inode waits for the io for the
1550 * inode to finish. So WB_SYNC_NONE is sent down to sync_inode
1551 * and filemap_fdatawrite is used for the data blocks
1552 */
1553 ret = sync_inode(inode, &wbc);
1554 if (!ret)
1555 ret = filemap_fdatawrite(mapping);
1556 return ret;
1557}
1558
1559/*
1560 * write data and metadata corresponding to i1 and i2. The io is
1561 * started but we do not wait for any of it to finish.
1562 *
1563 * filemap_flush is used for the block device, so if there is a dirty
1564 * page for a block already in flight, we will not wait and start the
1565 * io over again
1566 */
1567int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
1568{
1569 int ret = 0;
1570 if (!MSDOS_SB(sb)->options.flush)
1571 return 0;
1572 if (i1)
1573 ret = writeback_inode(i1);
1574 if (!ret && i2)
1575 ret = writeback_inode(i2);
Eric Sesterhenn97e860d2006-10-11 01:21:59 -07001576 if (!ret) {
Chris Masonae78bf92006-09-29 02:00:03 -07001577 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
1578 ret = filemap_flush(mapping);
1579 }
1580 return ret;
1581}
1582EXPORT_SYMBOL_GPL(fat_flush_inodes);
1583
Linus Torvalds1da177e2005-04-16 15:20:36 -07001584static int __init init_fat_fs(void)
1585{
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001586 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001588 err = fat_cache_init();
1589 if (err)
1590 return err;
1591
1592 err = fat_init_inodecache();
1593 if (err)
1594 goto failed;
1595
1596 return 0;
1597
1598failed:
1599 fat_cache_destroy();
1600 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001601}
1602
1603static void __exit exit_fat_fs(void)
1604{
1605 fat_cache_destroy();
1606 fat_destroy_inodecache();
1607}
1608
1609module_init(init_fat_fs)
1610module_exit(exit_fat_fs)
1611
1612MODULE_LICENSE("GPL");