blob: 509411dd3698959c0b8c387dcf0f487b5da12abe [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/pagemap.h>
OGAWA Hirofumia5425d22006-01-08 01:02:10 -080015#include <linux/mpage.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/vfs.h>
Alexander Kuleshov58932ef2015-04-16 12:47:24 -070017#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/parser.h>
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -080019#include <linux/uio.h>
Namjae Jeonf5621462012-12-17 16:02:56 -080020#include <linux/blkdev.h>
Tejun Heo66114ca2015-05-22 17:13:32 -040021#include <linux/backing-dev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <asm/unaligned.h>
OGAWA Hirofumi9e975da2008-11-06 12:53:46 -080023#include "fat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
25#ifndef CONFIG_FAT_DEFAULT_IOCHARSET
26/* if user don't select VFAT, this is undefined. */
27#define CONFIG_FAT_DEFAULT_IOCHARSET ""
28#endif
29
Conrad Meyer190a8842014-06-06 14:36:37 -070030#define KB_IN_SECTORS 2
31
32/*
33 * A deserialized copy of the on-disk structure laid out in struct
34 * fat_boot_sector.
35 */
36struct fat_bios_param_block {
37 u16 fat_sector_size;
38 u8 fat_sec_per_clus;
39 u16 fat_reserved;
40 u8 fat_fats;
41 u16 fat_dir_entries;
42 u16 fat_sectors;
43 u16 fat_fat_length;
44 u32 fat_total_sect;
45
46 u8 fat16_state;
47 u32 fat16_vol_id;
48
49 u32 fat32_length;
50 u32 fat32_root_cluster;
51 u16 fat32_info_sector;
52 u8 fat32_state;
53 u32 fat32_vol_id;
54};
55
Linus Torvalds1da177e2005-04-16 15:20:36 -070056static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
57static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
58
Conrad Meyer190a8842014-06-06 14:36:37 -070059static struct fat_floppy_defaults {
60 unsigned nr_sectors;
61 unsigned sec_per_clus;
62 unsigned dir_entries;
63 unsigned media;
64 unsigned fat_length;
65} floppy_defaults[] = {
66{
67 .nr_sectors = 160 * KB_IN_SECTORS,
68 .sec_per_clus = 1,
69 .dir_entries = 64,
70 .media = 0xFE,
71 .fat_length = 1,
72},
73{
74 .nr_sectors = 180 * KB_IN_SECTORS,
75 .sec_per_clus = 1,
76 .dir_entries = 64,
77 .media = 0xFC,
78 .fat_length = 2,
79},
80{
81 .nr_sectors = 320 * KB_IN_SECTORS,
82 .sec_per_clus = 2,
83 .dir_entries = 112,
84 .media = 0xFF,
85 .fat_length = 1,
86},
87{
88 .nr_sectors = 360 * KB_IN_SECTORS,
89 .sec_per_clus = 2,
90 .dir_entries = 112,
91 .media = 0xFD,
92 .fat_length = 2,
93},
94};
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96static int fat_add_cluster(struct inode *inode)
97{
98 int err, cluster;
99
100 err = fat_alloc_clusters(inode, &cluster, 1);
101 if (err)
102 return err;
103 /* FIXME: this cluster should be added after data of this
104 * cluster is writed */
105 err = fat_chain_add(inode, cluster, 1);
106 if (err)
107 fat_free_clusters(inode, cluster);
108 return err;
109}
110
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700111static inline int __fat_get_block(struct inode *inode, sector_t iblock,
112 unsigned long *max_blocks,
113 struct buffer_head *bh_result, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
115 struct super_block *sb = inode->i_sb;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800116 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800117 unsigned long mapped_blocks;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700118 sector_t phys;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800119 int err, offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -0800121 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 if (err)
123 return err;
124 if (phys) {
125 map_bh(bh_result, sb, phys);
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800126 *max_blocks = min(mapped_blocks, *max_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 return 0;
128 }
129 if (!create)
130 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800131
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
Denis Karpov85c78592009-06-04 02:34:22 +0900133 fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)",
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700134 MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 return -EIO;
136 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800137
138 offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
139 if (!offset) {
140 /* TODO: multiple cluster allocation would be desirable. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 err = fat_add_cluster(inode);
142 if (err)
143 return err;
144 }
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800145 /* available blocks on this cluster */
146 mapped_blocks = sbi->sec_per_clus - offset;
147
148 *max_blocks = min(mapped_blocks, *max_blocks);
149 MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
150
OGAWA Hirofumi2bdf67e2008-11-06 12:53:57 -0800151 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 if (err)
153 return err;
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700154
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800155 BUG_ON(!phys);
156 BUG_ON(*max_blocks != mapped_blocks);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 set_buffer_new(bh_result);
158 map_bh(bh_result, sb, phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800160 return 0;
161}
162
163static int fat_get_block(struct inode *inode, sector_t iblock,
164 struct buffer_head *bh_result, int create)
165{
OGAWA Hirofumi6a1d9802006-09-27 01:50:45 -0700166 struct super_block *sb = inode->i_sb;
167 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
168 int err;
169
170 err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create);
171 if (err)
172 return err;
173 bh_result->b_size = max_blocks << sb->s_blocksize_bits;
174 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800175}
176
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177static int fat_writepage(struct page *page, struct writeback_control *wbc)
178{
179 return block_write_full_page(page, fat_get_block, wbc);
180}
181
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800182static int fat_writepages(struct address_space *mapping,
183 struct writeback_control *wbc)
184{
185 return mpage_writepages(mapping, wbc, fat_get_block);
186}
187
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188static int fat_readpage(struct file *file, struct page *page)
189{
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800190 return mpage_readpage(page, fat_get_block);
191}
192
193static int fat_readpages(struct file *file, struct address_space *mapping,
194 struct list_head *pages, unsigned nr_pages)
195{
196 return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197}
198
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000199static void fat_write_failed(struct address_space *mapping, loff_t to)
200{
201 struct inode *inode = mapping->host;
202
203 if (to > inode->i_size) {
Kirill A. Shutemov7caef262013-09-12 15:13:56 -0700204 truncate_pagecache(inode, inode->i_size);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000205 fat_truncate_blocks(inode, inode->i_size);
206 }
207}
208
Nick Piggind7777a22007-10-16 01:25:08 -0700209static int fat_write_begin(struct file *file, struct address_space *mapping,
210 loff_t pos, unsigned len, unsigned flags,
211 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212{
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000213 int err;
214
Nick Piggind7777a22007-10-16 01:25:08 -0700215 *pagep = NULL;
Christoph Hellwig282dc172010-06-04 11:29:55 +0200216 err = cont_write_begin(file, mapping, pos, len, flags,
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000217 pagep, fsdata, fat_get_block,
Nick Piggind7777a22007-10-16 01:25:08 -0700218 &MSDOS_I(mapping->host)->mmu_private);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000219 if (err < 0)
220 fat_write_failed(mapping, pos + len);
221 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222}
223
Nick Piggind7777a22007-10-16 01:25:08 -0700224static int fat_write_end(struct file *file, struct address_space *mapping,
225 loff_t pos, unsigned len, unsigned copied,
226 struct page *pagep, void *fsdata)
OGAWA Hirofumief402262005-09-16 19:28:13 -0700227{
Nick Piggind7777a22007-10-16 01:25:08 -0700228 struct inode *inode = mapping->host;
229 int err;
230 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000231 if (err < len)
232 fat_write_failed(mapping, pos + len);
Nick Piggind7777a22007-10-16 01:25:08 -0700233 if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) {
OGAWA Hirofumief402262005-09-16 19:28:13 -0700234 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
235 MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
236 mark_inode_dirty(inode);
237 }
238 return err;
239}
240
Omar Sandoval22c61862015-03-16 04:33:53 -0700241static ssize_t fat_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
Al Virod8d3d942014-03-04 21:27:34 -0500242 loff_t offset)
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800243{
244 struct file *file = iocb->ki_filp;
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000245 struct address_space *mapping = file->f_mapping;
246 struct inode *inode = mapping->host;
Al Viroa6cbcd42014-03-04 22:38:00 -0500247 size_t count = iov_iter_count(iter);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000248 ssize_t ret;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800249
Omar Sandoval6f673762015-03-16 04:33:52 -0700250 if (iov_iter_rw(iter) == WRITE) {
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800251 /*
Nick Piggin4e02ed42008-10-29 14:00:55 -0700252 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800253 * so we need to update the ->mmu_private to block boundary.
254 *
255 * But we must fill the remaining area or hole by nul for
256 * updating ->mmu_private.
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800257 *
258 * Return 0, and fallback to normal buffered write.
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800259 */
Al Viroa6cbcd42014-03-04 22:38:00 -0500260 loff_t size = offset + count;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800261 if (MSDOS_I(inode)->mmu_private < size)
OGAWA Hirofumi94412a92007-02-20 13:57:55 -0800262 return 0;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800263 }
264
265 /*
266 * FAT need to use the DIO_LOCKING for avoiding the race
267 * condition of fat_get_block() and ->truncate().
268 */
Omar Sandoval17f8c842015-03-16 04:33:50 -0700269 ret = blockdev_direct_IO(iocb, inode, iter, offset, fat_get_block);
Omar Sandoval6f673762015-03-16 04:33:52 -0700270 if (ret < 0 && iov_iter_rw(iter) == WRITE)
Al Viroa6cbcd42014-03-04 22:38:00 -0500271 fat_write_failed(mapping, offset + count);
npiggin@suse.de459f6ed2010-05-27 01:05:38 +1000272
273 return ret;
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800274}
275
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
277{
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800278 sector_t blocknr;
279
280 /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
Christoph Hellwig58268692011-06-24 14:29:40 -0400281 down_read(&MSDOS_I(mapping->host)->truncate_lock);
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800282 blocknr = generic_block_bmap(mapping, block, fat_get_block);
Christoph Hellwig58268692011-06-24 14:29:40 -0400283 up_read(&MSDOS_I(mapping->host)->truncate_lock);
OGAWA Hirofumifa93ca12008-11-06 12:53:56 -0800284
285 return blocknr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286}
287
Namjae Jeonc0ef0cc2014-12-12 16:57:26 -0800288/*
289 * fat_block_truncate_page() zeroes out a mapping from file offset `from'
290 * up to the end of the block which corresponds to `from'.
291 * This is required during truncate to physically zeroout the tail end
292 * of that block so it doesn't yield old data if the file is later grown.
293 * Also, avoid causing failure from fsx for cases of "data past EOF"
294 */
295int fat_block_truncate_page(struct inode *inode, loff_t from)
296{
297 return block_truncate_page(inode->i_mapping, from, fat_get_block);
298}
299
Christoph Hellwigf5e54d62006-06-28 04:26:44 -0700300static const struct address_space_operations fat_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 .readpage = fat_readpage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800302 .readpages = fat_readpages,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 .writepage = fat_writepage,
OGAWA Hirofumia5425d22006-01-08 01:02:10 -0800304 .writepages = fat_writepages,
Nick Piggind7777a22007-10-16 01:25:08 -0700305 .write_begin = fat_write_begin,
306 .write_end = fat_write_end,
OGAWA Hirofumie5174ba2006-01-08 01:02:11 -0800307 .direct_IO = fat_direct_IO,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 .bmap = _fat_bmap
309};
310
311/*
312 * New FAT inode stuff. We do the following:
313 * a) i_ino is constant and has nothing with on-disk location.
314 * b) FAT manages its own cache of directory entries.
315 * c) *This* cache is indexed by on-disk location.
316 * d) inode has an associated directory entry, all right, but
317 * it may be unhashed.
318 * e) currently entries are stored within struct inode. That should
319 * change.
320 * f) we deal with races in the following way:
321 * 1. readdir() and lookup() do FAT-dir-cache lookup.
322 * 2. rename() unhashes the F-d-c entry and rehashes it in
323 * a new place.
324 * 3. unlink() and rmdir() unhash F-d-c entry.
325 * 4. fat_write_inode() checks whether the thing is unhashed.
326 * If it is we silently return. If it isn't we do bread(),
327 * check if the location is still valid and retry if it
328 * isn't. Otherwise we do changes.
329 * 5. Spinlock is used to protect hash/unhash/location check/lookup
Al Virodeee3ce2010-06-05 19:28:32 -0400330 * 6. fat_evict_inode() unhashes the F-d-c entry.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
332 * and consider negative result as cache miss.
333 */
334
335static void fat_hash_init(struct super_block *sb)
336{
337 struct msdos_sb_info *sbi = MSDOS_SB(sb);
338 int i;
339
340 spin_lock_init(&sbi->inode_hash_lock);
341 for (i = 0; i < FAT_HASH_SIZE; i++)
342 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
343}
344
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800345static inline unsigned long fat_hash(loff_t i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800347 return hash_32(i_pos, FAT_HASH_BITS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348}
349
Steven J. Magnani7669e8f2012-10-04 17:14:45 -0700350static void dir_hash_init(struct super_block *sb)
351{
352 struct msdos_sb_info *sbi = MSDOS_SB(sb);
353 int i;
354
355 spin_lock_init(&sbi->dir_hash_lock);
356 for (i = 0; i < FAT_HASH_SIZE; i++)
357 INIT_HLIST_HEAD(&sbi->dir_hashtable[i]);
358}
359
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360void fat_attach(struct inode *inode, loff_t i_pos)
361{
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800362 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363
Steven J. Magnani7669e8f2012-10-04 17:14:45 -0700364 if (inode->i_ino != MSDOS_ROOT_INO) {
365 struct hlist_head *head = sbi->inode_hashtable
366 + fat_hash(i_pos);
367
368 spin_lock(&sbi->inode_hash_lock);
369 MSDOS_I(inode)->i_pos = i_pos;
370 hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head);
371 spin_unlock(&sbi->inode_hash_lock);
372 }
373
374 /* If NFS support is enabled, cache the mapping of start cluster
375 * to directory inode. This is used during reconnection of
376 * dentries to the filesystem root.
377 */
378 if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
379 struct hlist_head *d_head = sbi->dir_hashtable;
380 d_head += fat_dir_hash(MSDOS_I(inode)->i_logstart);
381
382 spin_lock(&sbi->dir_hash_lock);
383 hlist_add_head(&MSDOS_I(inode)->i_dir_hash, d_head);
384 spin_unlock(&sbi->dir_hash_lock);
385 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800387EXPORT_SYMBOL_GPL(fat_attach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388
389void fat_detach(struct inode *inode)
390{
391 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
392 spin_lock(&sbi->inode_hash_lock);
393 MSDOS_I(inode)->i_pos = 0;
394 hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
395 spin_unlock(&sbi->inode_hash_lock);
Steven J. Magnani7669e8f2012-10-04 17:14:45 -0700396
397 if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
398 spin_lock(&sbi->dir_hash_lock);
399 hlist_del_init(&MSDOS_I(inode)->i_dir_hash);
400 spin_unlock(&sbi->dir_hash_lock);
401 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402}
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800403EXPORT_SYMBOL_GPL(fat_detach);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404
405struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
406{
407 struct msdos_sb_info *sbi = MSDOS_SB(sb);
OGAWA Hirofumid3dfa822008-11-06 12:53:49 -0800408 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 struct msdos_inode_info *i;
410 struct inode *inode = NULL;
411
412 spin_lock(&sbi->inode_hash_lock);
Sasha Levinb67bfe02013-02-27 17:06:00 -0800413 hlist_for_each_entry(i, head, i_fat_hash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 BUG_ON(i->vfs_inode.i_sb != sb);
415 if (i->i_pos != i_pos)
416 continue;
417 inode = igrab(&i->vfs_inode);
418 if (inode)
419 break;
420 }
421 spin_unlock(&sbi->inode_hash_lock);
422 return inode;
423}
424
425static int is_exec(unsigned char *extension)
426{
Manuel Schöllingef194702014-06-06 14:36:38 -0700427 unsigned char exe_extensions[] = "EXECOMBAT", *walk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
429 for (walk = exe_extensions; *walk; walk += 3)
430 if (!strncmp(extension, walk, 3))
431 return 1;
432 return 0;
433}
434
435static int fat_calc_dir_size(struct inode *inode)
436{
437 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
438 int ret, fclus, dclus;
439
440 inode->i_size = 0;
441 if (MSDOS_I(inode)->i_start == 0)
442 return 0;
443
444 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
445 if (ret < 0)
446 return ret;
447 inode->i_size = (fclus + 1) << sbi->cluster_bits;
448
449 return 0;
450}
451
452/* doesn't deal with root inode */
Namjae Jeonf1e6fb02013-04-29 16:21:14 -0700453int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454{
455 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
456 int error;
457
458 MSDOS_I(inode)->i_pos = 0;
459 inode->i_uid = sbi->options.fs_uid;
460 inode->i_gid = sbi->options.fs_gid;
461 inode->i_version++;
462 inode->i_generation = get_seconds();
463
464 if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
465 inode->i_generation &= ~1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800466 inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 inode->i_op = sbi->dir_ops;
468 inode->i_fop = &fat_dir_operations;
469
Steven J. Magnania943ed72012-07-30 14:42:13 -0700470 MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
472 error = fat_calc_dir_size(inode);
473 if (error < 0)
474 return error;
475 MSDOS_I(inode)->mmu_private = inode->i_size;
476
Miklos Szeredibfe86842011-10-28 14:13:29 +0200477 set_nlink(inode, fat_subdirs(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 } else { /* not a directory */
479 inode->i_generation |= 1;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800480 inode->i_mode = fat_make_mode(sbi, de->attr,
481 ((sbi->options.showexec && !is_exec(de->name + 8))
482 ? S_IRUGO|S_IWUGO : S_IRWXUGO));
Steven J. Magnania943ed72012-07-30 14:42:13 -0700483 MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
485 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
486 inode->i_size = le32_to_cpu(de->size);
487 inode->i_op = &fat_file_inode_operations;
488 inode->i_fop = &fat_file_operations;
489 inode->i_mapping->a_ops = &fat_aops;
490 MSDOS_I(inode)->mmu_private = inode->i_size;
491 }
492 if (de->attr & ATTR_SYS) {
493 if (sbi->options.sys_immutable)
494 inode->i_flags |= S_IMMUTABLE;
495 }
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800496 fat_save_attrs(inode, de->attr);
497
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
499 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800500
501 fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 if (sbi->options.isvfat) {
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800503 fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
504 de->cdate, de->ctime_cs);
505 fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 } else
Stephane Kardas62a36c42005-09-21 09:55:45 -0700507 inode->i_ctime = inode->i_atime = inode->i_mtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508
509 return 0;
510}
511
Namjae Jeon8fceb4e2013-04-29 16:21:12 -0700512static inline void fat_lock_build_inode(struct msdos_sb_info *sbi)
513{
514 if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
515 mutex_lock(&sbi->nfs_build_inode_lock);
516}
517
518static inline void fat_unlock_build_inode(struct msdos_sb_info *sbi)
519{
520 if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
521 mutex_unlock(&sbi->nfs_build_inode_lock);
522}
523
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524struct inode *fat_build_inode(struct super_block *sb,
525 struct msdos_dir_entry *de, loff_t i_pos)
526{
527 struct inode *inode;
528 int err;
529
Namjae Jeon8fceb4e2013-04-29 16:21:12 -0700530 fat_lock_build_inode(MSDOS_SB(sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 inode = fat_iget(sb, i_pos);
532 if (inode)
533 goto out;
534 inode = new_inode(sb);
535 if (!inode) {
536 inode = ERR_PTR(-ENOMEM);
537 goto out;
538 }
539 inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
540 inode->i_version = 1;
541 err = fat_fill_inode(inode, de);
542 if (err) {
543 iput(inode);
544 inode = ERR_PTR(err);
545 goto out;
546 }
547 fat_attach(inode, i_pos);
548 insert_inode_hash(inode);
549out:
Namjae Jeon8fceb4e2013-04-29 16:21:12 -0700550 fat_unlock_build_inode(MSDOS_SB(sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 return inode;
552}
553
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800554EXPORT_SYMBOL_GPL(fat_build_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555
Al Virodeee3ce2010-06-05 19:28:32 -0400556static void fat_evict_inode(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557{
Johannes Weiner91b0abe2014-04-03 14:47:49 -0700558 truncate_inode_pages_final(&inode->i_data);
Al Virodeee3ce2010-06-05 19:28:32 -0400559 if (!inode->i_nlink) {
560 inode->i_size = 0;
561 fat_truncate_blocks(inode, 0);
562 }
563 invalidate_inode_buffers(inode);
Jan Karadbd57682012-05-03 14:48:02 +0200564 clear_inode(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 fat_cache_inval_inode(inode);
OGAWA Hirofumia993b542008-11-06 12:53:50 -0800566 fat_detach(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567}
568
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800569static void fat_set_state(struct super_block *sb,
570 unsigned int set, unsigned int force)
571{
572 struct buffer_head *bh;
573 struct fat_boot_sector *b;
Fred Choud6bd4282015-02-17 13:45:36 -0800574 struct msdos_sb_info *sbi = MSDOS_SB(sb);
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800575
576 /* do not change any thing if mounted read only */
577 if ((sb->s_flags & MS_RDONLY) && !force)
578 return;
579
580 /* do not change state if fs was dirty */
581 if (sbi->dirty) {
582 /* warn only on set (mount). */
583 if (set)
584 fat_msg(sb, KERN_WARNING, "Volume was not properly "
585 "unmounted. Some data may be corrupt. "
586 "Please run fsck.");
587 return;
588 }
589
590 bh = sb_bread(sb, 0);
591 if (bh == NULL) {
592 fat_msg(sb, KERN_ERR, "unable to read boot sector "
593 "to mark fs as dirty");
594 return;
595 }
596
597 b = (struct fat_boot_sector *) bh->b_data;
598
599 if (sbi->fat_bits == 32) {
600 if (set)
601 b->fat32.state |= FAT_STATE_DIRTY;
602 else
603 b->fat32.state &= ~FAT_STATE_DIRTY;
604 } else /* fat 16 and 12 */ {
605 if (set)
606 b->fat16.state |= FAT_STATE_DIRTY;
607 else
608 b->fat16.state &= ~FAT_STATE_DIRTY;
609 }
610
611 mark_buffer_dirty(bh);
612 sync_dirty_buffer(bh);
613 brelse(bh);
614}
615
Al Virocac45b02013-10-03 13:16:50 -0400616static void delayed_free(struct rcu_head *p)
617{
618 struct msdos_sb_info *sbi = container_of(p, struct msdos_sb_info, rcu);
619 unload_nls(sbi->nls_disk);
620 unload_nls(sbi->nls_io);
621 if (sbi->options.iocharset != fat_default_iocharset)
622 kfree(sbi->options.iocharset);
623 kfree(sbi);
624}
625
OGAWA Hirofumia6bf6b22006-01-08 01:02:08 -0800626static void fat_put_super(struct super_block *sb)
627{
628 struct msdos_sb_info *sbi = MSDOS_SB(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800630 fat_set_state(sb, 0, 0);
631
Artem Bityutskiy020ac5b2012-05-31 16:26:12 -0700632 iput(sbi->fsinfo_inode);
Al Virob5224122009-06-07 13:44:36 -0400633 iput(sbi->fat_inode);
634
Al Virocac45b02013-10-03 13:16:50 -0400635 call_rcu(&sbi->rcu, delayed_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636}
637
Christoph Lametere18b8902006-12-06 20:33:20 -0800638static struct kmem_cache *fat_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
640static struct inode *fat_alloc_inode(struct super_block *sb)
641{
642 struct msdos_inode_info *ei;
Linus Torvalds8f593422008-05-19 19:53:01 -0700643 ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 if (!ei)
645 return NULL;
Christoph Hellwig58268692011-06-24 14:29:40 -0400646
647 init_rwsem(&ei->truncate_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 return &ei->vfs_inode;
649}
650
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +1100651static void fat_i_callback(struct rcu_head *head)
652{
653 struct inode *inode = container_of(head, struct inode, i_rcu);
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +1100654 kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
655}
656
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657static void fat_destroy_inode(struct inode *inode)
658{
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +1100659 call_rcu(&inode->i_rcu, fat_i_callback);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660}
661
Alexey Dobriyan51cc5062008-07-25 19:45:34 -0700662static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663{
664 struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
665
Christoph Lametera35afb82007-05-16 22:10:57 -0700666 spin_lock_init(&ei->cache_lru_lock);
667 ei->nr_caches = 0;
668 ei->cache_valid_id = FAT_CACHE_VALID + 1;
669 INIT_LIST_HEAD(&ei->cache_lru);
670 INIT_HLIST_NODE(&ei->i_fat_hash);
Steven J. Magnani7669e8f2012-10-04 17:14:45 -0700671 INIT_HLIST_NODE(&ei->i_dir_hash);
Christoph Lametera35afb82007-05-16 22:10:57 -0700672 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673}
674
675static int __init fat_init_inodecache(void)
676{
677 fat_inode_cachep = kmem_cache_create("fat_inode_cache",
678 sizeof(struct msdos_inode_info),
Paul Jacksonfffb60f2006-03-24 03:16:06 -0800679 0, (SLAB_RECLAIM_ACCOUNT|
680 SLAB_MEM_SPREAD),
Paul Mundt20c2df82007-07-20 10:11:58 +0900681 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 if (fat_inode_cachep == NULL)
683 return -ENOMEM;
684 return 0;
685}
686
687static void __exit fat_destroy_inodecache(void)
688{
Kirill A. Shutemov8c0a8532012-09-26 11:33:07 +1000689 /*
690 * Make sure all delayed rcu free inodes are flushed before we
691 * destroy cache.
692 */
693 rcu_barrier();
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -0700694 kmem_cache_destroy(fat_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695}
696
697static int fat_remount(struct super_block *sb, int *flags, char *data)
698{
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800699 int new_rdonly;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 struct msdos_sb_info *sbi = MSDOS_SB(sb);
701 *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800702
Theodore Ts'o02b99842014-03-13 10:14:33 -0400703 sync_filesystem(sb);
704
Oleksij Rempelb88a10582013-02-27 17:03:09 -0800705 /* make sure we update state on remount. */
706 new_rdonly = *flags & MS_RDONLY;
707 if (new_rdonly != (sb->s_flags & MS_RDONLY)) {
708 if (new_rdonly)
709 fat_set_state(sb, 0, 0);
710 else
711 fat_set_state(sb, 1, 1);
712 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 return 0;
714}
715
David Howells726c3342006-06-23 02:02:58 -0700716static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
Coly Liaac49b72009-04-02 16:59:35 -0700718 struct super_block *sb = dentry->d_sb;
719 struct msdos_sb_info *sbi = MSDOS_SB(sb);
720 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721
722 /* If the count of free cluster is still unknown, counts it here. */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -0700723 if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
David Howells726c3342006-06-23 02:02:58 -0700724 int err = fat_count_free_clusters(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 if (err)
726 return err;
727 }
728
David Howells726c3342006-06-23 02:02:58 -0700729 buf->f_type = dentry->d_sb->s_magic;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 buf->f_bsize = sbi->cluster_size;
731 buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
732 buf->f_bfree = sbi->free_clusters;
733 buf->f_bavail = sbi->free_clusters;
Coly Liaac49b72009-04-02 16:59:35 -0700734 buf->f_fsid.val[0] = (u32)id;
735 buf->f_fsid.val[1] = (u32)(id >> 32);
OGAWA Hirofumif68e5422011-04-12 21:08:39 +0900736 buf->f_namelen =
737 (sbi->options.isvfat ? FAT_LFN_LEN : 12) * NLS_MAX_CHARSET_SIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738
739 return 0;
740}
741
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100742static int __fat_write_inode(struct inode *inode, int wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743{
744 struct super_block *sb = inode->i_sb;
745 struct msdos_sb_info *sbi = MSDOS_SB(sb);
746 struct buffer_head *bh;
747 struct msdos_dir_entry *raw_entry;
748 loff_t i_pos;
Namjae Jeone22a4442013-04-29 16:21:10 -0700749 sector_t blocknr;
750 int err, offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800752 if (inode->i_ino == MSDOS_ROOT_INO)
753 return 0;
754
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755retry:
OGAWA Hirofumi9ca59f42008-11-06 12:53:57 -0800756 i_pos = fat_i_pos_read(sbi, inode);
757 if (!i_pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 return 0;
759
Namjae Jeone22a4442013-04-29 16:21:10 -0700760 fat_get_blknr_offset(sbi, i_pos, &blocknr, &offset);
761 bh = sb_bread(sb, blocknr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 if (!bh) {
Alexey Fisher869f58c2011-04-12 21:08:38 +0900763 fat_msg(sb, KERN_ERR, "unable to read inode block "
764 "for updating (i_pos %lld)", i_pos);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700765 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 }
767 spin_lock(&sbi->inode_hash_lock);
768 if (i_pos != MSDOS_I(inode)->i_pos) {
769 spin_unlock(&sbi->inode_hash_lock);
770 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 goto retry;
772 }
773
Namjae Jeone22a4442013-04-29 16:21:10 -0700774 raw_entry = &((struct msdos_dir_entry *) (bh->b_data))[offset];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 if (S_ISDIR(inode->i_mode))
776 raw_entry->size = 0;
777 else
778 raw_entry->size = cpu_to_le32(inode->i_size);
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -0800779 raw_entry->attr = fat_make_attrs(inode);
Steven J. Magnania943ed72012-07-30 14:42:13 -0700780 fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart);
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800781 fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
782 &raw_entry->date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 if (sbi->options.isvfat) {
Stephane Kardas62a36c42005-09-21 09:55:45 -0700784 __le16 atime;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800785 fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
786 &raw_entry->cdate, &raw_entry->ctime_cs);
787 fat_time_unix2fat(sbi, &inode->i_atime, &atime,
788 &raw_entry->adate, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 }
790 spin_unlock(&sbi->inode_hash_lock);
791 mark_buffer_dirty(bh);
Linus Torvalds5f22ca92008-08-20 08:31:19 -0700792 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 if (wait)
794 err = sync_dirty_buffer(bh);
795 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 return err;
797}
798
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100799static int fat_write_inode(struct inode *inode, struct writeback_control *wbc)
800{
Artem Bityutskiy78491182012-05-31 16:26:13 -0700801 int err;
802
803 if (inode->i_ino == MSDOS_FSINFO_INO) {
804 struct super_block *sb = inode->i_sb;
805
Marco Stornellie40b34c2012-10-06 12:40:03 +0200806 mutex_lock(&MSDOS_SB(sb)->s_lock);
Artem Bityutskiy78491182012-05-31 16:26:13 -0700807 err = fat_clusters_flush(sb);
Marco Stornellie40b34c2012-10-06 12:40:03 +0200808 mutex_unlock(&MSDOS_SB(sb)->s_lock);
Artem Bityutskiy78491182012-05-31 16:26:13 -0700809 } else
810 err = __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
811
812 return err;
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100813}
814
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815int fat_sync_inode(struct inode *inode)
816{
Christoph Hellwiga9185b42010-03-05 09:21:37 +0100817 return __fat_write_inode(inode, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818}
819
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -0800820EXPORT_SYMBOL_GPL(fat_sync_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821
Al Viro34c80b12011-12-08 21:32:45 -0500822static int fat_show_options(struct seq_file *m, struct dentry *root);
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800823static const struct super_operations fat_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 .alloc_inode = fat_alloc_inode,
825 .destroy_inode = fat_destroy_inode,
826 .write_inode = fat_write_inode,
Al Virodeee3ce2010-06-05 19:28:32 -0400827 .evict_inode = fat_evict_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 .put_super = fat_put_super,
829 .statfs = fat_statfs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 .remount_fs = fat_remount,
831
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 .show_options = fat_show_options,
833};
834
Al Viro34c80b12011-12-08 21:32:45 -0500835static int fat_show_options(struct seq_file *m, struct dentry *root)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836{
Al Viro34c80b12011-12-08 21:32:45 -0500837 struct msdos_sb_info *sbi = MSDOS_SB(root->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 struct fat_mount_options *opts = &sbi->options;
839 int isvfat = opts->isvfat;
840
Eric W. Biederman170782e2012-02-07 16:25:39 -0800841 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID))
842 seq_printf(m, ",uid=%u",
843 from_kuid_munged(&init_user_ns, opts->fs_uid));
844 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID))
845 seq_printf(m, ",gid=%u",
846 from_kgid_munged(&init_user_ns, opts->fs_gid));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 seq_printf(m, ",fmask=%04o", opts->fs_fmask);
848 seq_printf(m, ",dmask=%04o", opts->fs_dmask);
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700849 if (opts->allow_utime)
850 seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 if (sbi->nls_disk)
Dave Reisnerc6c20372012-12-17 16:03:01 -0800852 /* strip "cp" prefix from displayed option */
853 seq_printf(m, ",codepage=%s", &sbi->nls_disk->charset[2]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 if (isvfat) {
855 if (sbi->nls_io)
856 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
857
858 switch (opts->shortname) {
859 case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
860 seq_puts(m, ",shortname=win95");
861 break;
862 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
863 seq_puts(m, ",shortname=winnt");
864 break;
865 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
866 seq_puts(m, ",shortname=mixed");
867 break;
868 case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
Paul Wise95523472009-08-01 21:30:31 +0900869 seq_puts(m, ",shortname=lower");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 break;
871 default:
872 seq_puts(m, ",shortname=unknown");
873 break;
874 }
875 }
876 if (opts->name_check != 'n')
877 seq_printf(m, ",check=%c", opts->name_check);
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700878 if (opts->usefree)
879 seq_puts(m, ",usefree");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 if (opts->quiet)
881 seq_puts(m, ",quiet");
882 if (opts->showexec)
883 seq_puts(m, ",showexec");
884 if (opts->sys_immutable)
885 seq_puts(m, ",sys_immutable");
886 if (!isvfat) {
887 if (opts->dotsOK)
888 seq_puts(m, ",dotsOK=yes");
889 if (opts->nocase)
890 seq_puts(m, ",nocase");
891 } else {
892 if (opts->utf8)
893 seq_puts(m, ",utf8");
894 if (opts->unicode_xlate)
895 seq_puts(m, ",uni_xlate");
896 if (!opts->numtail)
897 seq_puts(m, ",nonumtail");
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800898 if (opts->rodir)
899 seq_puts(m, ",rodir");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900 }
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -0800901 if (opts->flush)
Miklos Szeredic1fca3b2008-02-08 04:21:42 -0800902 seq_puts(m, ",flush");
Jan Kara58156c82012-12-17 16:02:58 -0800903 if (opts->tz_set) {
904 if (opts->time_offset)
905 seq_printf(m, ",time_offset=%d", opts->time_offset);
906 else
907 seq_puts(m, ",tz=UTC");
908 }
Denis Karpov85c78592009-06-04 02:34:22 +0900909 if (opts->errors == FAT_ERRORS_CONT)
910 seq_puts(m, ",errors=continue");
911 else if (opts->errors == FAT_ERRORS_PANIC)
912 seq_puts(m, ",errors=panic");
913 else
914 seq_puts(m, ",errors=remount-ro");
Namjae Jeon2628b7a2013-04-29 16:21:08 -0700915 if (opts->nfs == FAT_NFS_NOSTALE_RO)
916 seq_puts(m, ",nfs=nostale_ro");
917 else if (opts->nfs)
918 seq_puts(m, ",nfs=stale_rw");
Christoph Hellwig681142f2009-11-21 20:28:52 +0900919 if (opts->discard)
920 seq_puts(m, ",discard");
Conrad Meyer190a8842014-06-06 14:36:37 -0700921 if (opts->dos1xfloppy)
922 seq_puts(m, ",dos1xfloppy");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923
924 return 0;
925}
926
927enum {
928 Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700929 Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage,
930 Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug,
931 Opt_immutable, Opt_dots, Opt_nodots,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
933 Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
934 Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
Geert Uytterhoevend7a83c02011-10-31 20:50:45 +0100935 Opt_obsolete, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont,
Jan Kara58156c82012-12-17 16:02:58 -0800936 Opt_err_panic, Opt_err_ro, Opt_discard, Opt_nfs, Opt_time_offset,
Conrad Meyer190a8842014-06-06 14:36:37 -0700937 Opt_nfs_stale_rw, Opt_nfs_nostale_ro, Opt_err, Opt_dos1xfloppy,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938};
939
Steven Whitehousea447c092008-10-13 10:46:57 +0100940static const match_table_t fat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941 {Opt_check_r, "check=relaxed"},
942 {Opt_check_s, "check=strict"},
943 {Opt_check_n, "check=normal"},
944 {Opt_check_r, "check=r"},
945 {Opt_check_s, "check=s"},
946 {Opt_check_n, "check=n"},
947 {Opt_uid, "uid=%u"},
948 {Opt_gid, "gid=%u"},
949 {Opt_umask, "umask=%o"},
950 {Opt_dmask, "dmask=%o"},
951 {Opt_fmask, "fmask=%o"},
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -0700952 {Opt_allow_utime, "allow_utime=%o"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 {Opt_codepage, "codepage=%u"},
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -0700954 {Opt_usefree, "usefree"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 {Opt_nocase, "nocase"},
956 {Opt_quiet, "quiet"},
957 {Opt_showexec, "showexec"},
958 {Opt_debug, "debug"},
959 {Opt_immutable, "sys_immutable"},
Denis Karpov85c78592009-06-04 02:34:22 +0900960 {Opt_flush, "flush"},
961 {Opt_tz_utc, "tz=UTC"},
Jan Kara58156c82012-12-17 16:02:58 -0800962 {Opt_time_offset, "time_offset=%d"},
Denis Karpov85c78592009-06-04 02:34:22 +0900963 {Opt_err_cont, "errors=continue"},
964 {Opt_err_panic, "errors=panic"},
965 {Opt_err_ro, "errors=remount-ro"},
Christoph Hellwig681142f2009-11-21 20:28:52 +0900966 {Opt_discard, "discard"},
Namjae Jeon2628b7a2013-04-29 16:21:08 -0700967 {Opt_nfs_stale_rw, "nfs"},
968 {Opt_nfs_stale_rw, "nfs=stale_rw"},
969 {Opt_nfs_nostale_ro, "nfs=nostale_ro"},
Conrad Meyer190a8842014-06-06 14:36:37 -0700970 {Opt_dos1xfloppy, "dos1xfloppy"},
Geert Uytterhoevend7a83c02011-10-31 20:50:45 +0100971 {Opt_obsolete, "conv=binary"},
972 {Opt_obsolete, "conv=text"},
973 {Opt_obsolete, "conv=auto"},
974 {Opt_obsolete, "conv=b"},
975 {Opt_obsolete, "conv=t"},
976 {Opt_obsolete, "conv=a"},
977 {Opt_obsolete, "fat=%u"},
978 {Opt_obsolete, "blocksize=%u"},
979 {Opt_obsolete, "cvf_format=%20s"},
980 {Opt_obsolete, "cvf_options=%100s"},
981 {Opt_obsolete, "posix"},
Chris Masonae78bf92006-09-29 02:00:03 -0700982 {Opt_err, NULL},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983};
Steven Whitehousea447c092008-10-13 10:46:57 +0100984static const match_table_t msdos_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 {Opt_nodots, "nodots"},
986 {Opt_nodots, "dotsOK=no"},
987 {Opt_dots, "dots"},
988 {Opt_dots, "dotsOK=yes"},
989 {Opt_err, NULL}
990};
Steven Whitehousea447c092008-10-13 10:46:57 +0100991static const match_table_t vfat_tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 {Opt_charset, "iocharset=%s"},
993 {Opt_shortname_lower, "shortname=lower"},
994 {Opt_shortname_win95, "shortname=win95"},
995 {Opt_shortname_winnt, "shortname=winnt"},
996 {Opt_shortname_mixed, "shortname=mixed"},
997 {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
998 {Opt_utf8_no, "utf8=no"},
999 {Opt_utf8_no, "utf8=false"},
1000 {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
1001 {Opt_utf8_yes, "utf8=yes"},
1002 {Opt_utf8_yes, "utf8=true"},
1003 {Opt_utf8_yes, "utf8"},
1004 {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
1005 {Opt_uni_xl_no, "uni_xlate=no"},
1006 {Opt_uni_xl_no, "uni_xlate=false"},
1007 {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
1008 {Opt_uni_xl_yes, "uni_xlate=yes"},
1009 {Opt_uni_xl_yes, "uni_xlate=true"},
1010 {Opt_uni_xl_yes, "uni_xlate"},
1011 {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
1012 {Opt_nonumtail_no, "nonumtail=no"},
1013 {Opt_nonumtail_no, "nonumtail=false"},
1014 {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
1015 {Opt_nonumtail_yes, "nonumtail=yes"},
1016 {Opt_nonumtail_yes, "nonumtail=true"},
1017 {Opt_nonumtail_yes, "nonumtail"},
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001018 {Opt_rodir, "rodir"},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 {Opt_err, NULL}
1020};
1021
Alexey Fisher869f58c2011-04-12 21:08:38 +09001022static int parse_options(struct super_block *sb, char *options, int is_vfat,
1023 int silent, int *debug, struct fat_mount_options *opts)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024{
1025 char *p;
1026 substring_t args[MAX_OPT_ARGS];
1027 int option;
1028 char *iocharset;
1029
1030 opts->isvfat = is_vfat;
1031
David Howellsf0ce7ee2008-11-14 10:38:52 +11001032 opts->fs_uid = current_uid();
1033 opts->fs_gid = current_gid();
OGAWA Hirofumi3e107602009-06-20 21:50:07 +09001034 opts->fs_fmask = opts->fs_dmask = current_umask();
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001035 opts->allow_utime = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036 opts->codepage = fat_default_codepage;
1037 opts->iocharset = fat_default_iocharset;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001038 if (is_vfat) {
Paul Wise95523472009-08-01 21:30:31 +09001039 opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001040 opts->rodir = 0;
1041 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042 opts->shortname = 0;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001043 opts->rodir = 1;
1044 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 opts->name_check = 'n';
1046 opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
1047 opts->utf8 = opts->unicode_xlate = 0;
1048 opts->numtail = 1;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001049 opts->usefree = opts->nocase = 0;
Jan Kara58156c82012-12-17 16:02:58 -08001050 opts->tz_set = 0;
Steven J. Magnani7669e8f2012-10-04 17:14:45 -07001051 opts->nfs = 0;
Denis Karpov85c78592009-06-04 02:34:22 +09001052 opts->errors = FAT_ERRORS_RO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 *debug = 0;
1054
1055 if (!options)
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001056 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057
1058 while ((p = strsep(&options, ",")) != NULL) {
1059 int token;
1060 if (!*p)
1061 continue;
1062
1063 token = match_token(p, fat_tokens, args);
1064 if (token == Opt_err) {
1065 if (is_vfat)
1066 token = match_token(p, vfat_tokens, args);
1067 else
1068 token = match_token(p, msdos_tokens, args);
1069 }
1070 switch (token) {
1071 case Opt_check_s:
1072 opts->name_check = 's';
1073 break;
1074 case Opt_check_r:
1075 opts->name_check = 'r';
1076 break;
1077 case Opt_check_n:
1078 opts->name_check = 'n';
1079 break;
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001080 case Opt_usefree:
1081 opts->usefree = 1;
1082 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 case Opt_nocase:
1084 if (!is_vfat)
1085 opts->nocase = 1;
1086 else {
1087 /* for backward compatibility */
1088 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1089 | VFAT_SFN_CREATE_WIN95;
1090 }
1091 break;
1092 case Opt_quiet:
1093 opts->quiet = 1;
1094 break;
1095 case Opt_showexec:
1096 opts->showexec = 1;
1097 break;
1098 case Opt_debug:
1099 *debug = 1;
1100 break;
1101 case Opt_immutable:
1102 opts->sys_immutable = 1;
1103 break;
1104 case Opt_uid:
1105 if (match_int(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001106 return -EINVAL;
Eric W. Biederman170782e2012-02-07 16:25:39 -08001107 opts->fs_uid = make_kuid(current_user_ns(), option);
1108 if (!uid_valid(opts->fs_uid))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001109 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 break;
1111 case Opt_gid:
1112 if (match_int(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001113 return -EINVAL;
Eric W. Biederman170782e2012-02-07 16:25:39 -08001114 opts->fs_gid = make_kgid(current_user_ns(), option);
1115 if (!gid_valid(opts->fs_gid))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001116 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 break;
1118 case Opt_umask:
1119 if (match_octal(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001120 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121 opts->fs_fmask = opts->fs_dmask = option;
1122 break;
1123 case Opt_dmask:
1124 if (match_octal(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001125 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 opts->fs_dmask = option;
1127 break;
1128 case Opt_fmask:
1129 if (match_octal(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001130 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 opts->fs_fmask = option;
1132 break;
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001133 case Opt_allow_utime:
1134 if (match_octal(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001135 return -EINVAL;
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001136 opts->allow_utime = option & (S_IWGRP | S_IWOTH);
1137 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138 case Opt_codepage:
1139 if (match_int(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001140 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 opts->codepage = option;
1142 break;
Chris Masonae78bf92006-09-29 02:00:03 -07001143 case Opt_flush:
1144 opts->flush = 1;
1145 break;
Jan Kara58156c82012-12-17 16:02:58 -08001146 case Opt_time_offset:
1147 if (match_int(&args[0], &option))
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001148 return -EINVAL;
Jan Kara58156c82012-12-17 16:02:58 -08001149 if (option < -12 * 60 || option > 12 * 60)
Jan Kara5b3d5ae2012-12-17 16:02:59 -08001150 return -EINVAL;
Jan Kara58156c82012-12-17 16:02:58 -08001151 opts->tz_set = 1;
1152 opts->time_offset = option;
1153 break;
Joe Petersonb271e062008-07-25 01:46:47 -07001154 case Opt_tz_utc:
Jan Kara58156c82012-12-17 16:02:58 -08001155 opts->tz_set = 1;
1156 opts->time_offset = 0;
Joe Petersonb271e062008-07-25 01:46:47 -07001157 break;
Denis Karpov85c78592009-06-04 02:34:22 +09001158 case Opt_err_cont:
1159 opts->errors = FAT_ERRORS_CONT;
1160 break;
1161 case Opt_err_panic:
1162 opts->errors = FAT_ERRORS_PANIC;
1163 break;
1164 case Opt_err_ro:
1165 opts->errors = FAT_ERRORS_RO;
1166 break;
Namjae Jeon2628b7a2013-04-29 16:21:08 -07001167 case Opt_nfs_stale_rw:
1168 opts->nfs = FAT_NFS_STALE_RW;
1169 break;
1170 case Opt_nfs_nostale_ro:
1171 opts->nfs = FAT_NFS_NOSTALE_RO;
1172 break;
Conrad Meyer190a8842014-06-06 14:36:37 -07001173 case Opt_dos1xfloppy:
1174 opts->dos1xfloppy = 1;
1175 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176
1177 /* msdos specific */
1178 case Opt_dots:
1179 opts->dotsOK = 1;
1180 break;
1181 case Opt_nodots:
1182 opts->dotsOK = 0;
1183 break;
1184
1185 /* vfat specific */
1186 case Opt_charset:
1187 if (opts->iocharset != fat_default_iocharset)
1188 kfree(opts->iocharset);
1189 iocharset = match_strdup(&args[0]);
1190 if (!iocharset)
1191 return -ENOMEM;
1192 opts->iocharset = iocharset;
1193 break;
1194 case Opt_shortname_lower:
1195 opts->shortname = VFAT_SFN_DISPLAY_LOWER
1196 | VFAT_SFN_CREATE_WIN95;
1197 break;
1198 case Opt_shortname_win95:
1199 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1200 | VFAT_SFN_CREATE_WIN95;
1201 break;
1202 case Opt_shortname_winnt:
1203 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1204 | VFAT_SFN_CREATE_WINNT;
1205 break;
1206 case Opt_shortname_mixed:
1207 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1208 | VFAT_SFN_CREATE_WIN95;
1209 break;
1210 case Opt_utf8_no: /* 0 or no or false */
1211 opts->utf8 = 0;
1212 break;
1213 case Opt_utf8_yes: /* empty or 1 or yes or true */
1214 opts->utf8 = 1;
1215 break;
1216 case Opt_uni_xl_no: /* 0 or no or false */
1217 opts->unicode_xlate = 0;
1218 break;
1219 case Opt_uni_xl_yes: /* empty or 1 or yes or true */
1220 opts->unicode_xlate = 1;
1221 break;
1222 case Opt_nonumtail_no: /* 0 or no or false */
1223 opts->numtail = 1; /* negated option */
1224 break;
1225 case Opt_nonumtail_yes: /* empty or 1 or yes or true */
1226 opts->numtail = 0; /* negated option */
1227 break;
OGAWA Hirofumidfc209c2008-11-06 12:53:55 -08001228 case Opt_rodir:
1229 opts->rodir = 1;
1230 break;
Christoph Hellwig681142f2009-11-21 20:28:52 +09001231 case Opt_discard:
1232 opts->discard = 1;
1233 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234
1235 /* obsolete mount options */
Geert Uytterhoevend7a83c02011-10-31 20:50:45 +01001236 case Opt_obsolete:
Alexey Fisher869f58c2011-04-12 21:08:38 +09001237 fat_msg(sb, KERN_INFO, "\"%s\" option is obsolete, "
1238 "not supported now", p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001239 break;
1240 /* unknown option */
1241 default:
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001242 if (!silent) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001243 fat_msg(sb, KERN_ERR,
1244 "Unrecognized mount option \"%s\" "
1245 "or missing value", p);
Christoph Hellwig41a34a42005-11-08 21:34:57 -08001246 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247 return -EINVAL;
1248 }
1249 }
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001250
1251out:
Alexey Dobriyan4de151d2006-03-22 00:13:35 +01001252 /* UTF-8 doesn't provide FAT semantics */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001253 if (!strcmp(opts->iocharset, "utf8")) {
Mihai Moldovan186b5372011-08-17 19:10:08 +09001254 fat_msg(sb, KERN_WARNING, "utf8 is not a recommended IO charset"
OGAWA Hirofumi8d44d972008-07-25 01:46:41 -07001255 " for FAT filesystems, filesystem will be "
Mihai Moldovan186b5372011-08-17 19:10:08 +09001256 "case sensitive!");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 }
1258
OGAWA Hirofumi1ae43f82008-04-28 02:16:26 -07001259 /* If user doesn't specify allow_utime, it's initialized from dmask. */
1260 if (opts->allow_utime == (unsigned short)-1)
1261 opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 if (opts->unicode_xlate)
1263 opts->utf8 = 0;
Namjae Jeonea3983a2013-04-29 16:21:11 -07001264 if (opts->nfs == FAT_NFS_NOSTALE_RO) {
Namjae Jeon2628b7a2013-04-29 16:21:08 -07001265 sb->s_flags |= MS_RDONLY;
Namjae Jeonea3983a2013-04-29 16:21:11 -07001266 sb->s_export_op = &fat_export_ops_nostale;
1267 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268
1269 return 0;
1270}
1271
1272static int fat_read_root(struct inode *inode)
1273{
Alexander Kuleshova40a7d92015-04-16 12:47:21 -07001274 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275 int error;
1276
Namjae Jeonea3983a2013-04-29 16:21:11 -07001277 MSDOS_I(inode)->i_pos = MSDOS_ROOT_INO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278 inode->i_uid = sbi->options.fs_uid;
1279 inode->i_gid = sbi->options.fs_gid;
1280 inode->i_version++;
1281 inode->i_generation = 0;
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001282 inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283 inode->i_op = sbi->dir_ops;
1284 inode->i_fop = &fat_dir_operations;
1285 if (sbi->fat_bits == 32) {
1286 MSDOS_I(inode)->i_start = sbi->root_cluster;
1287 error = fat_calc_dir_size(inode);
1288 if (error < 0)
1289 return error;
1290 } else {
1291 MSDOS_I(inode)->i_start = 0;
1292 inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
1293 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
1295 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
1296 MSDOS_I(inode)->i_logstart = 0;
1297 MSDOS_I(inode)->mmu_private = inode->i_size;
1298
OGAWA Hirofumi9c0aa1b2008-11-06 12:53:54 -08001299 fat_save_attrs(inode, ATTR_DIR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
1301 inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
Miklos Szeredibfe86842011-10-28 14:13:29 +02001302 set_nlink(inode, fat_subdirs(inode)+2);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303
1304 return 0;
1305}
1306
OGAWA Hirofumi7b92d032013-05-24 15:55:08 -07001307static unsigned long calc_fat_clusters(struct super_block *sb)
1308{
1309 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1310
1311 /* Divide first to avoid overflow */
1312 if (sbi->fat_bits != 12) {
1313 unsigned long ent_per_sec = sb->s_blocksize * 8 / sbi->fat_bits;
1314 return ent_per_sec * sbi->fat_length;
1315 }
1316
1317 return sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
1318}
1319
Conrad Meyer190a8842014-06-06 14:36:37 -07001320static bool fat_bpb_is_zero(struct fat_boot_sector *b)
1321{
1322 if (get_unaligned_le16(&b->sector_size))
1323 return false;
1324 if (b->sec_per_clus)
1325 return false;
1326 if (b->reserved)
1327 return false;
1328 if (b->fats)
1329 return false;
1330 if (get_unaligned_le16(&b->dir_entries))
1331 return false;
1332 if (get_unaligned_le16(&b->sectors))
1333 return false;
1334 if (b->media)
1335 return false;
1336 if (b->fat_length)
1337 return false;
1338 if (b->secs_track)
1339 return false;
1340 if (b->heads)
1341 return false;
1342 return true;
1343}
1344
1345static int fat_read_bpb(struct super_block *sb, struct fat_boot_sector *b,
1346 int silent, struct fat_bios_param_block *bpb)
1347{
1348 int error = -EINVAL;
1349
1350 /* Read in BPB ... */
1351 memset(bpb, 0, sizeof(*bpb));
1352 bpb->fat_sector_size = get_unaligned_le16(&b->sector_size);
1353 bpb->fat_sec_per_clus = b->sec_per_clus;
1354 bpb->fat_reserved = le16_to_cpu(b->reserved);
1355 bpb->fat_fats = b->fats;
1356 bpb->fat_dir_entries = get_unaligned_le16(&b->dir_entries);
1357 bpb->fat_sectors = get_unaligned_le16(&b->sectors);
1358 bpb->fat_fat_length = le16_to_cpu(b->fat_length);
1359 bpb->fat_total_sect = le32_to_cpu(b->total_sect);
1360
1361 bpb->fat16_state = b->fat16.state;
1362 bpb->fat16_vol_id = get_unaligned_le32(b->fat16.vol_id);
1363
1364 bpb->fat32_length = le32_to_cpu(b->fat32.length);
1365 bpb->fat32_root_cluster = le32_to_cpu(b->fat32.root_cluster);
1366 bpb->fat32_info_sector = le16_to_cpu(b->fat32.info_sector);
1367 bpb->fat32_state = b->fat32.state;
1368 bpb->fat32_vol_id = get_unaligned_le32(b->fat32.vol_id);
1369
1370 /* Validate this looks like a FAT filesystem BPB */
1371 if (!bpb->fat_reserved) {
1372 if (!silent)
1373 fat_msg(sb, KERN_ERR,
1374 "bogus number of reserved sectors");
1375 goto out;
1376 }
1377 if (!bpb->fat_fats) {
1378 if (!silent)
1379 fat_msg(sb, KERN_ERR, "bogus number of FAT structure");
1380 goto out;
1381 }
1382
1383 /*
1384 * Earlier we checked here that b->secs_track and b->head are nonzero,
1385 * but it turns out valid FAT filesystems can have zero there.
1386 */
1387
1388 if (!fat_valid_media(b->media)) {
1389 if (!silent)
1390 fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)",
1391 (unsigned)b->media);
1392 goto out;
1393 }
1394
1395 if (!is_power_of_2(bpb->fat_sector_size)
1396 || (bpb->fat_sector_size < 512)
1397 || (bpb->fat_sector_size > 4096)) {
1398 if (!silent)
1399 fat_msg(sb, KERN_ERR, "bogus logical sector size %u",
1400 (unsigned)bpb->fat_sector_size);
1401 goto out;
1402 }
1403
1404 if (!is_power_of_2(bpb->fat_sec_per_clus)) {
1405 if (!silent)
1406 fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u",
1407 (unsigned)bpb->fat_sec_per_clus);
1408 goto out;
1409 }
1410
1411 error = 0;
1412
1413out:
1414 return error;
1415}
1416
1417static int fat_read_static_bpb(struct super_block *sb,
1418 struct fat_boot_sector *b, int silent,
1419 struct fat_bios_param_block *bpb)
1420{
1421 static const char *notdos1x = "This doesn't look like a DOS 1.x volume";
1422
1423 struct fat_floppy_defaults *fdefaults = NULL;
1424 int error = -EINVAL;
1425 sector_t bd_sects;
1426 unsigned i;
1427
1428 bd_sects = i_size_read(sb->s_bdev->bd_inode) / SECTOR_SIZE;
1429
1430 /* 16-bit DOS 1.x reliably wrote bootstrap short-jmp code */
1431 if (b->ignored[0] != 0xeb || b->ignored[2] != 0x90) {
1432 if (!silent)
1433 fat_msg(sb, KERN_ERR,
1434 "%s; no bootstrapping code", notdos1x);
1435 goto out;
1436 }
1437
1438 /*
1439 * If any value in this region is non-zero, it isn't archaic
1440 * DOS.
1441 */
1442 if (!fat_bpb_is_zero(b)) {
1443 if (!silent)
1444 fat_msg(sb, KERN_ERR,
1445 "%s; DOS 2.x BPB is non-zero", notdos1x);
1446 goto out;
1447 }
1448
1449 for (i = 0; i < ARRAY_SIZE(floppy_defaults); i++) {
1450 if (floppy_defaults[i].nr_sectors == bd_sects) {
1451 fdefaults = &floppy_defaults[i];
1452 break;
1453 }
1454 }
1455
1456 if (fdefaults == NULL) {
1457 if (!silent)
1458 fat_msg(sb, KERN_WARNING,
1459 "This looks like a DOS 1.x volume, but isn't a recognized floppy size (%llu sectors)",
1460 (u64)bd_sects);
1461 goto out;
1462 }
1463
1464 if (!silent)
1465 fat_msg(sb, KERN_INFO,
1466 "This looks like a DOS 1.x volume; assuming default BPB values");
1467
1468 memset(bpb, 0, sizeof(*bpb));
1469 bpb->fat_sector_size = SECTOR_SIZE;
1470 bpb->fat_sec_per_clus = fdefaults->sec_per_clus;
1471 bpb->fat_reserved = 1;
1472 bpb->fat_fats = 2;
1473 bpb->fat_dir_entries = fdefaults->dir_entries;
1474 bpb->fat_sectors = fdefaults->nr_sectors;
1475 bpb->fat_fat_length = fdefaults->fat_length;
1476
1477 error = 0;
1478
1479out:
1480 return error;
1481}
1482
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483/*
1484 * Read the super block of an MS-DOS FS.
1485 */
OGAWA Hirofumi384f5c92011-04-12 21:08:37 +09001486int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
Al Viro3d239852010-12-18 10:44:00 -05001487 void (*setup)(struct super_block *))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001488{
Al Virob5224122009-06-07 13:44:36 -04001489 struct inode *root_inode = NULL, *fat_inode = NULL;
Artem Bityutskiy020ac5b2012-05-31 16:26:12 -07001490 struct inode *fsinfo_inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491 struct buffer_head *bh;
Conrad Meyer190a8842014-06-06 14:36:37 -07001492 struct fat_bios_param_block bpb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001493 struct msdos_sb_info *sbi;
1494 u16 logical_sector_size;
1495 u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
1496 int debug;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 long error;
1498 char buf[50];
1499
Linus Torvalds8f593422008-05-19 19:53:01 -07001500 /*
1501 * GFP_KERNEL is ok here, because while we do hold the
1502 * supeblock lock, memory pressure can't call back into
1503 * the filesystem, since we're only just about to mount
1504 * it and have no inodes etc active!
1505 */
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -07001506 sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507 if (!sbi)
1508 return -ENOMEM;
1509 sb->s_fs_info = sbi;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001510
1511 sb->s_flags |= MS_NODIRATIME;
1512 sb->s_magic = MSDOS_SUPER_MAGIC;
1513 sb->s_op = &fat_sops;
1514 sb->s_export_op = &fat_export_ops;
Namjae Jeon8fceb4e2013-04-29 16:21:12 -07001515 mutex_init(&sbi->nfs_build_inode_lock);
OGAWA Hirofumiaaa04b42010-05-24 14:33:12 -07001516 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
1517 DEFAULT_RATELIMIT_BURST);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518
Alexey Fisher869f58c2011-04-12 21:08:38 +09001519 error = parse_options(sb, data, isvfat, silent, &debug, &sbi->options);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 if (error)
1521 goto out_fail;
1522
Al Viro3d239852010-12-18 10:44:00 -05001523 setup(sb); /* flavour-specific stuff that needs options */
1524
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525 error = -EIO;
1526 sb_min_blocksize(sb, 512);
1527 bh = sb_bread(sb, 0);
1528 if (bh == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001529 fat_msg(sb, KERN_ERR, "unable to read boot sector");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530 goto out_fail;
1531 }
1532
Conrad Meyer190a8842014-06-06 14:36:37 -07001533 error = fat_read_bpb(sb, (struct fat_boot_sector *)bh->b_data, silent,
1534 &bpb);
1535 if (error == -EINVAL && sbi->options.dos1xfloppy)
1536 error = fat_read_static_bpb(sb,
1537 (struct fat_boot_sector *)bh->b_data, silent, &bpb);
1538 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539
Conrad Meyer190a8842014-06-06 14:36:37 -07001540 if (error == -EINVAL)
1541 goto out_invalid;
1542 else if (error)
1543 goto out_fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544
Conrad Meyer190a8842014-06-06 14:36:37 -07001545 logical_sector_size = bpb.fat_sector_size;
1546 sbi->sec_per_clus = bpb.fat_sec_per_clus;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001547
Conrad Meyer190a8842014-06-06 14:36:37 -07001548 error = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549 if (logical_sector_size < sb->s_blocksize) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001550 fat_msg(sb, KERN_ERR, "logical sector size too small for device"
1551 " (logical sector size = %u)", logical_sector_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001552 goto out_fail;
1553 }
Conrad Meyer190a8842014-06-06 14:36:37 -07001554
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 if (logical_sector_size > sb->s_blocksize) {
Conrad Meyer190a8842014-06-06 14:36:37 -07001556 struct buffer_head *bh_resize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557
1558 if (!sb_set_blocksize(sb, logical_sector_size)) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001559 fat_msg(sb, KERN_ERR, "unable to set blocksize %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560 logical_sector_size);
1561 goto out_fail;
1562 }
Conrad Meyer190a8842014-06-06 14:36:37 -07001563
1564 /* Verify that the larger boot sector is fully readable */
1565 bh_resize = sb_bread(sb, 0);
1566 if (bh_resize == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001567 fat_msg(sb, KERN_ERR, "unable to read boot sector"
1568 " (logical sector size = %lu)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 sb->s_blocksize);
1570 goto out_fail;
1571 }
Conrad Meyer190a8842014-06-06 14:36:37 -07001572 brelse(bh_resize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 }
1574
Marco Stornellie40b34c2012-10-06 12:40:03 +02001575 mutex_init(&sbi->s_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576 sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
1577 sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
Conrad Meyer190a8842014-06-06 14:36:37 -07001578 sbi->fats = bpb.fat_fats;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579 sbi->fat_bits = 0; /* Don't know yet */
Conrad Meyer190a8842014-06-06 14:36:37 -07001580 sbi->fat_start = bpb.fat_reserved;
1581 sbi->fat_length = bpb.fat_fat_length;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001582 sbi->root_cluster = 0;
1583 sbi->free_clusters = -1; /* Don't know yet */
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001584 sbi->free_clus_valid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585 sbi->prev_free = FAT_START_ENT;
Namjae Jeon710d4402011-08-17 19:10:09 +09001586 sb->s_maxbytes = 0xffffffff;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587
Conrad Meyer190a8842014-06-06 14:36:37 -07001588 if (!sbi->fat_length && bpb.fat32_length) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589 struct fat_boot_fsinfo *fsinfo;
1590 struct buffer_head *fsinfo_bh;
1591
1592 /* Must be FAT32 */
1593 sbi->fat_bits = 32;
Conrad Meyer190a8842014-06-06 14:36:37 -07001594 sbi->fat_length = bpb.fat32_length;
1595 sbi->root_cluster = bpb.fat32_root_cluster;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001596
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 /* MC - if info_sector is 0, don't multiply by 0 */
Conrad Meyer190a8842014-06-06 14:36:37 -07001598 sbi->fsinfo_sector = bpb.fat32_info_sector;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599 if (sbi->fsinfo_sector == 0)
1600 sbi->fsinfo_sector = 1;
1601
1602 fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
1603 if (fsinfo_bh == NULL) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001604 fat_msg(sb, KERN_ERR, "bread failed, FSINFO block"
1605 " (sector = %lu)", sbi->fsinfo_sector);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001606 goto out_fail;
1607 }
1608
1609 fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
1610 if (!IS_FSINFO(fsinfo)) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001611 fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: "
1612 "0x%08x, 0x%08x (sector = %lu)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613 le32_to_cpu(fsinfo->signature1),
1614 le32_to_cpu(fsinfo->signature2),
1615 sbi->fsinfo_sector);
1616 } else {
OGAWA Hirofumi28ec0392007-05-08 00:31:01 -07001617 if (sbi->options.usefree)
OGAWA Hirofumi606e4232008-04-28 02:16:27 -07001618 sbi->free_clus_valid = 1;
1619 sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
1621 }
1622
1623 brelse(fsinfo_bh);
1624 }
1625
Mike Lockwood6e5b93e2013-07-08 16:00:46 -07001626 /* interpret volume ID as a little endian 32 bit integer */
1627 if (sbi->fat_bits == 32)
Conrad Meyer190a8842014-06-06 14:36:37 -07001628 sbi->vol_id = bpb.fat32_vol_id;
Mike Lockwood6e5b93e2013-07-08 16:00:46 -07001629 else /* fat 16 or 12 */
Conrad Meyer190a8842014-06-06 14:36:37 -07001630 sbi->vol_id = bpb.fat16_vol_id;
Mike Lockwood6e5b93e2013-07-08 16:00:46 -07001631
Linus Torvalds1da177e2005-04-16 15:20:36 -07001632 sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
1633 sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
1634
1635 sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
Conrad Meyer190a8842014-06-06 14:36:37 -07001636 sbi->dir_entries = bpb.fat_dir_entries;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637 if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
1638 if (!silent)
Ravishankar Nc39540c2012-12-20 15:05:46 -08001639 fat_msg(sb, KERN_ERR, "bogus directory-entries per block"
Alexey Fisher869f58c2011-04-12 21:08:38 +09001640 " (%u)", sbi->dir_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 goto out_invalid;
1642 }
1643
1644 rootdir_sectors = sbi->dir_entries
1645 * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
1646 sbi->data_start = sbi->dir_start + rootdir_sectors;
Conrad Meyer190a8842014-06-06 14:36:37 -07001647 total_sectors = bpb.fat_sectors;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648 if (total_sectors == 0)
Conrad Meyer190a8842014-06-06 14:36:37 -07001649 total_sectors = bpb.fat_total_sect;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001650
1651 total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
1652
1653 if (sbi->fat_bits != 32)
1654 sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
1655
Oleksij Rempelb88a10582013-02-27 17:03:09 -08001656 /* some OSes set FAT_STATE_DIRTY and clean it on unmount. */
1657 if (sbi->fat_bits == 32)
Conrad Meyer190a8842014-06-06 14:36:37 -07001658 sbi->dirty = bpb.fat32_state & FAT_STATE_DIRTY;
Oleksij Rempelb88a10582013-02-27 17:03:09 -08001659 else /* fat 16 or 12 */
Conrad Meyer190a8842014-06-06 14:36:37 -07001660 sbi->dirty = bpb.fat16_state & FAT_STATE_DIRTY;
Oleksij Rempelb88a10582013-02-27 17:03:09 -08001661
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662 /* check that FAT table does not overflow */
OGAWA Hirofumi7b92d032013-05-24 15:55:08 -07001663 fat_clusters = calc_fat_clusters(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
1665 if (total_clusters > MAX_FAT(sb)) {
1666 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001667 fat_msg(sb, KERN_ERR, "count of clusters too big (%u)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001668 total_clusters);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 goto out_invalid;
1670 }
1671
1672 sbi->max_cluster = total_clusters + FAT_START_ENT;
1673 /* check the free_clusters, it's not necessarily correct */
1674 if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
1675 sbi->free_clusters = -1;
1676 /* check the prev_free, it's not necessarily correct */
1677 sbi->prev_free %= sbi->max_cluster;
1678 if (sbi->prev_free < FAT_START_ENT)
1679 sbi->prev_free = FAT_START_ENT;
1680
Linus Torvalds1da177e2005-04-16 15:20:36 -07001681 /* set up enough so that it can read an inode */
1682 fat_hash_init(sb);
Steven J. Magnani7669e8f2012-10-04 17:14:45 -07001683 dir_hash_init(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684 fat_ent_access_init(sb);
1685
1686 /*
1687 * The low byte of FAT's first entry must have same value with
1688 * media-field. But in real world, too many devices is
1689 * writing wrong value. So, removed that validity check.
1690 *
1691 * if (FAT_FIRST_ENT(sb, media) != first)
1692 */
1693
1694 error = -EINVAL;
1695 sprintf(buf, "cp%d", sbi->options.codepage);
1696 sbi->nls_disk = load_nls(buf);
1697 if (!sbi->nls_disk) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001698 fat_msg(sb, KERN_ERR, "codepage %s not found", buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001699 goto out_fail;
1700 }
1701
1702 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1703 if (sbi->options.isvfat) {
1704 sbi->nls_io = load_nls(sbi->options.iocharset);
1705 if (!sbi->nls_io) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001706 fat_msg(sb, KERN_ERR, "IO charset %s not found",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001707 sbi->options.iocharset);
1708 goto out_fail;
1709 }
1710 }
1711
1712 error = -ENOMEM;
Al Virob5224122009-06-07 13:44:36 -04001713 fat_inode = new_inode(sb);
1714 if (!fat_inode)
1715 goto out_fail;
1716 MSDOS_I(fat_inode)->i_pos = 0;
1717 sbi->fat_inode = fat_inode;
Artem Bityutskiy020ac5b2012-05-31 16:26:12 -07001718
1719 fsinfo_inode = new_inode(sb);
1720 if (!fsinfo_inode)
1721 goto out_fail;
1722 fsinfo_inode->i_ino = MSDOS_FSINFO_INO;
1723 sbi->fsinfo_inode = fsinfo_inode;
1724 insert_inode_hash(fsinfo_inode);
1725
Linus Torvalds1da177e2005-04-16 15:20:36 -07001726 root_inode = new_inode(sb);
1727 if (!root_inode)
1728 goto out_fail;
1729 root_inode->i_ino = MSDOS_ROOT_INO;
1730 root_inode->i_version = 1;
1731 error = fat_read_root(root_inode);
Al Viro1688f862012-02-12 22:06:33 -05001732 if (error < 0) {
1733 iput(root_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734 goto out_fail;
Al Viro1688f862012-02-12 22:06:33 -05001735 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001736 error = -ENOMEM;
1737 insert_inode_hash(root_inode);
Steven J. Magnani7669e8f2012-10-04 17:14:45 -07001738 fat_attach(root_inode, 0);
Al Viro1688f862012-02-12 22:06:33 -05001739 sb->s_root = d_make_root(root_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740 if (!sb->s_root) {
Alexey Fisher869f58c2011-04-12 21:08:38 +09001741 fat_msg(sb, KERN_ERR, "get root inode failed");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742 goto out_fail;
1743 }
1744
Namjae Jeonf5621462012-12-17 16:02:56 -08001745 if (sbi->options.discard) {
1746 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1747 if (!blk_queue_discard(q))
1748 fat_msg(sb, KERN_WARNING,
1749 "mounting with \"discard\" option, but "
1750 "the device does not support discard");
1751 }
1752
Oleksij Rempelb88a10582013-02-27 17:03:09 -08001753 fat_set_state(sb, 1, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 return 0;
1755
1756out_invalid:
1757 error = -EINVAL;
1758 if (!silent)
Alexey Fisher869f58c2011-04-12 21:08:38 +09001759 fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001760
1761out_fail:
Artem Bityutskiy020ac5b2012-05-31 16:26:12 -07001762 if (fsinfo_inode)
1763 iput(fsinfo_inode);
Al Virob5224122009-06-07 13:44:36 -04001764 if (fat_inode)
1765 iput(fat_inode);
OGAWA Hirofumi1bdb6f92010-03-16 05:48:09 +09001766 unload_nls(sbi->nls_io);
1767 unload_nls(sbi->nls_disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001768 if (sbi->options.iocharset != fat_default_iocharset)
1769 kfree(sbi->options.iocharset);
1770 sb->s_fs_info = NULL;
1771 kfree(sbi);
1772 return error;
1773}
1774
OGAWA Hirofumi7c709d02006-01-08 01:02:10 -08001775EXPORT_SYMBOL_GPL(fat_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001776
Chris Masonae78bf92006-09-29 02:00:03 -07001777/*
1778 * helper function for fat_flush_inodes. This writes both the inode
1779 * and the file data blocks, waiting for in flight data blocks before
1780 * the start of the call. It does not wait for any io started
1781 * during the call
1782 */
1783static int writeback_inode(struct inode *inode)
1784{
1785
1786 int ret;
Namjae Jeon14864652012-10-04 17:15:04 -07001787
1788 /* if we used wait=1, sync_inode_metadata waits for the io for the
1789 * inode to finish. So wait=0 is sent down to sync_inode_metadata
Chris Masonae78bf92006-09-29 02:00:03 -07001790 * and filemap_fdatawrite is used for the data blocks
1791 */
Namjae Jeon14864652012-10-04 17:15:04 -07001792 ret = sync_inode_metadata(inode, 0);
Chris Masonae78bf92006-09-29 02:00:03 -07001793 if (!ret)
Namjae Jeon14864652012-10-04 17:15:04 -07001794 ret = filemap_fdatawrite(inode->i_mapping);
Chris Masonae78bf92006-09-29 02:00:03 -07001795 return ret;
1796}
1797
1798/*
1799 * write data and metadata corresponding to i1 and i2. The io is
1800 * started but we do not wait for any of it to finish.
1801 *
1802 * filemap_flush is used for the block device, so if there is a dirty
1803 * page for a block already in flight, we will not wait and start the
1804 * io over again
1805 */
1806int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
1807{
1808 int ret = 0;
1809 if (!MSDOS_SB(sb)->options.flush)
1810 return 0;
1811 if (i1)
1812 ret = writeback_inode(i1);
1813 if (!ret && i2)
1814 ret = writeback_inode(i2);
Eric Sesterhenn97e860d2006-10-11 01:21:59 -07001815 if (!ret) {
Chris Masonae78bf92006-09-29 02:00:03 -07001816 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
1817 ret = filemap_flush(mapping);
1818 }
1819 return ret;
1820}
1821EXPORT_SYMBOL_GPL(fat_flush_inodes);
1822
Linus Torvalds1da177e2005-04-16 15:20:36 -07001823static int __init init_fat_fs(void)
1824{
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001825 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001826
Pekka J Enberg532a39a2005-06-30 02:59:01 -07001827 err = fat_cache_init();
1828 if (err)
1829 return err;
1830
1831 err = fat_init_inodecache();
1832 if (err)
1833 goto failed;
1834
1835 return 0;
1836
1837failed:
1838 fat_cache_destroy();
1839 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001840}
1841
1842static void __exit exit_fat_fs(void)
1843{
1844 fat_cache_destroy();
1845 fat_destroy_inodecache();
1846}
1847
1848module_init(init_fat_fs)
1849module_exit(exit_fat_fs)
1850
1851MODULE_LICENSE("GPL");