1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4 */
5
6#include <linux/fs_context.h>
7#include <linux/fs_parser.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/time.h>
11#include <linux/mount.h>
12#include <linux/cred.h>
13#include <linux/statfs.h>
14#include <linux/seq_file.h>
15#include <linux/blkdev.h>
16#include <linux/fs_struct.h>
17#include <linux/iversion.h>
18#include <linux/nls.h>
19#include <linux/buffer_head.h>
20#include <linux/magic.h>
21
22#include "exfat_raw.h"
23#include "exfat_fs.h"
24
25static char exfat_default_iocharset[] = CONFIG_EXFAT_DEFAULT_IOCHARSET;
26static struct kmem_cache *exfat_inode_cachep;
27
28static void exfat_free_iocharset(struct exfat_sb_info *sbi)
29{
30	if (sbi->options.iocharset != exfat_default_iocharset)
31		kfree(sbi->options.iocharset);
32}
33
34static void exfat_put_super(struct super_block *sb)
35{
36	struct exfat_sb_info *sbi = EXFAT_SB(sb);
37
38	mutex_lock(&sbi->s_lock);
39	exfat_free_bitmap(sbi);
40	brelse(sbi->boot_bh);
41	mutex_unlock(&sbi->s_lock);
42}
43
44static int exfat_sync_fs(struct super_block *sb, int wait)
45{
46	struct exfat_sb_info *sbi = EXFAT_SB(sb);
47	int err = 0;
48
49	if (!wait)
50		return 0;
51
52	/* If there are some dirty buffers in the bdev inode */
53	mutex_lock(&sbi->s_lock);
54	sync_blockdev(sb->s_bdev);
55	if (exfat_clear_volume_dirty(sb))
56		err = -EIO;
57	mutex_unlock(&sbi->s_lock);
58	return err;
59}
60
61static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf)
62{
63	struct super_block *sb = dentry->d_sb;
64	struct exfat_sb_info *sbi = EXFAT_SB(sb);
65	unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev);
66
67	if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) {
68		mutex_lock(&sbi->s_lock);
69		if (exfat_count_used_clusters(sb, &sbi->used_clusters)) {
70			mutex_unlock(&sbi->s_lock);
71			return -EIO;
72		}
73		mutex_unlock(&sbi->s_lock);
74	}
75
76	buf->f_type = sb->s_magic;
77	buf->f_bsize = sbi->cluster_size;
78	buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */
79	buf->f_bfree = buf->f_blocks - sbi->used_clusters;
80	buf->f_bavail = buf->f_bfree;
81	buf->f_fsid = u64_to_fsid(id);
82	/* Unicode utf16 255 characters */
83	buf->f_namelen = EXFAT_MAX_FILE_LEN * NLS_MAX_CHARSET_SIZE;
84	return 0;
85}
86
87static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags)
88{
89	struct exfat_sb_info *sbi = EXFAT_SB(sb);
90	struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
91
92	/* retain persistent-flags */
93	new_flags |= sbi->vol_flags_persistent;
94
95	/* flags are not changed */
96	if (sbi->vol_flags == new_flags)
97		return 0;
98
99	sbi->vol_flags = new_flags;
100
101	/* skip updating volume dirty flag,
102	 * if this volume has been mounted with read-only
103	 */
104	if (sb_rdonly(sb))
105		return 0;
106
107	p_boot->vol_flags = cpu_to_le16(new_flags);
108
109	set_buffer_uptodate(sbi->boot_bh);
110	mark_buffer_dirty(sbi->boot_bh);
111
112	__sync_dirty_buffer(sbi->boot_bh, REQ_SYNC | REQ_FUA | REQ_PREFLUSH);
113
114	return 0;
115}
116
117int exfat_set_volume_dirty(struct super_block *sb)
118{
119	struct exfat_sb_info *sbi = EXFAT_SB(sb);
120
121	return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY);
122}
123
124int exfat_clear_volume_dirty(struct super_block *sb)
125{
126	struct exfat_sb_info *sbi = EXFAT_SB(sb);
127
128	return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY);
129}
130
131static int exfat_show_options(struct seq_file *m, struct dentry *root)
132{
133	struct super_block *sb = root->d_sb;
134	struct exfat_sb_info *sbi = EXFAT_SB(sb);
135	struct exfat_mount_options *opts = &sbi->options;
136
137	/* Show partition info */
138	if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID))
139		seq_printf(m, ",uid=%u",
140				from_kuid_munged(&init_user_ns, opts->fs_uid));
141	if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID))
142		seq_printf(m, ",gid=%u",
143				from_kgid_munged(&init_user_ns, opts->fs_gid));
144	seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask);
145	if (opts->allow_utime)
146		seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
147	if (opts->utf8)
148		seq_puts(m, ",iocharset=utf8");
149	else if (sbi->nls_io)
150		seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
151	if (opts->errors == EXFAT_ERRORS_CONT)
152		seq_puts(m, ",errors=continue");
153	else if (opts->errors == EXFAT_ERRORS_PANIC)
154		seq_puts(m, ",errors=panic");
155	else
156		seq_puts(m, ",errors=remount-ro");
157	if (opts->discard)
158		seq_puts(m, ",discard");
159	if (opts->keep_last_dots)
160		seq_puts(m, ",keep_last_dots");
161	if (opts->sys_tz)
162		seq_puts(m, ",sys_tz");
163	else if (opts->time_offset)
164		seq_printf(m, ",time_offset=%d", opts->time_offset);
165	if (opts->zero_size_dir)
166		seq_puts(m, ",zero_size_dir");
167	return 0;
168}
169
170static struct inode *exfat_alloc_inode(struct super_block *sb)
171{
172	struct exfat_inode_info *ei;
173
174	ei = alloc_inode_sb(sb, exfat_inode_cachep, GFP_NOFS);
175	if (!ei)
176		return NULL;
177
178	init_rwsem(&ei->truncate_lock);
179	return &ei->vfs_inode;
180}
181
182static void exfat_free_inode(struct inode *inode)
183{
184	kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode));
185}
186
187static const struct super_operations exfat_sops = {
188	.alloc_inode	= exfat_alloc_inode,
189	.free_inode	= exfat_free_inode,
190	.write_inode	= exfat_write_inode,
191	.evict_inode	= exfat_evict_inode,
192	.put_super	= exfat_put_super,
193	.sync_fs	= exfat_sync_fs,
194	.statfs		= exfat_statfs,
195	.show_options	= exfat_show_options,
196};
197
198enum {
199	Opt_uid,
200	Opt_gid,
201	Opt_umask,
202	Opt_dmask,
203	Opt_fmask,
204	Opt_allow_utime,
205	Opt_charset,
206	Opt_errors,
207	Opt_discard,
208	Opt_keep_last_dots,
209	Opt_sys_tz,
210	Opt_time_offset,
211	Opt_zero_size_dir,
212
213	/* Deprecated options */
214	Opt_utf8,
215	Opt_debug,
216	Opt_namecase,
217	Opt_codepage,
218};
219
220static const struct constant_table exfat_param_enums[] = {
221	{ "continue",		EXFAT_ERRORS_CONT },
222	{ "panic",		EXFAT_ERRORS_PANIC },
223	{ "remount-ro",		EXFAT_ERRORS_RO },
224	{}
225};
226
227static const struct fs_parameter_spec exfat_parameters[] = {
228	fsparam_u32("uid",			Opt_uid),
229	fsparam_u32("gid",			Opt_gid),
230	fsparam_u32oct("umask",			Opt_umask),
231	fsparam_u32oct("dmask",			Opt_dmask),
232	fsparam_u32oct("fmask",			Opt_fmask),
233	fsparam_u32oct("allow_utime",		Opt_allow_utime),
234	fsparam_string("iocharset",		Opt_charset),
235	fsparam_enum("errors",			Opt_errors, exfat_param_enums),
236	fsparam_flag("discard",			Opt_discard),
237	fsparam_flag("keep_last_dots",		Opt_keep_last_dots),
238	fsparam_flag("sys_tz",			Opt_sys_tz),
239	fsparam_s32("time_offset",		Opt_time_offset),
240	fsparam_flag("zero_size_dir",		Opt_zero_size_dir),
241	__fsparam(NULL, "utf8",			Opt_utf8, fs_param_deprecated,
242		  NULL),
243	__fsparam(NULL, "debug",		Opt_debug, fs_param_deprecated,
244		  NULL),
245	__fsparam(fs_param_is_u32, "namecase",	Opt_namecase,
246		  fs_param_deprecated, NULL),
247	__fsparam(fs_param_is_u32, "codepage",	Opt_codepage,
248		  fs_param_deprecated, NULL),
249	{}
250};
251
252static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param)
253{
254	struct exfat_sb_info *sbi = fc->s_fs_info;
255	struct exfat_mount_options *opts = &sbi->options;
256	struct fs_parse_result result;
257	int opt;
258
259	opt = fs_parse(fc, exfat_parameters, param, &result);
260	if (opt < 0)
261		return opt;
262
263	switch (opt) {
264	case Opt_uid:
265		opts->fs_uid = make_kuid(current_user_ns(), result.uint_32);
266		break;
267	case Opt_gid:
268		opts->fs_gid = make_kgid(current_user_ns(), result.uint_32);
269		break;
270	case Opt_umask:
271		opts->fs_fmask = result.uint_32;
272		opts->fs_dmask = result.uint_32;
273		break;
274	case Opt_dmask:
275		opts->fs_dmask = result.uint_32;
276		break;
277	case Opt_fmask:
278		opts->fs_fmask = result.uint_32;
279		break;
280	case Opt_allow_utime:
281		opts->allow_utime = result.uint_32 & 0022;
282		break;
283	case Opt_charset:
284		exfat_free_iocharset(sbi);
285		opts->iocharset = param->string;
286		param->string = NULL;
287		break;
288	case Opt_errors:
289		opts->errors = result.uint_32;
290		break;
291	case Opt_discard:
292		opts->discard = 1;
293		break;
294	case Opt_keep_last_dots:
295		opts->keep_last_dots = 1;
296		break;
297	case Opt_sys_tz:
298		opts->sys_tz = 1;
299		break;
300	case Opt_time_offset:
301		/*
302		 * Make the limit 24 just in case someone invents something
303		 * unusual.
304		 */
305		if (result.int_32 < -24 * 60 || result.int_32 > 24 * 60)
306			return -EINVAL;
307		opts->time_offset = result.int_32;
308		break;
309	case Opt_zero_size_dir:
310		opts->zero_size_dir = true;
311		break;
312	case Opt_utf8:
313	case Opt_debug:
314	case Opt_namecase:
315	case Opt_codepage:
316		break;
317	default:
318		return -EINVAL;
319	}
320
321	return 0;
322}
323
324static void exfat_hash_init(struct super_block *sb)
325{
326	struct exfat_sb_info *sbi = EXFAT_SB(sb);
327	int i;
328
329	spin_lock_init(&sbi->inode_hash_lock);
330	for (i = 0; i < EXFAT_HASH_SIZE; i++)
331		INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
332}
333
334static int exfat_read_root(struct inode *inode)
335{
336	struct super_block *sb = inode->i_sb;
337	struct exfat_sb_info *sbi = EXFAT_SB(sb);
338	struct exfat_inode_info *ei = EXFAT_I(inode);
339	struct exfat_chain cdir;
340	int num_subdirs, num_clu = 0;
341
342	exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
343	ei->entry = -1;
344	ei->start_clu = sbi->root_dir;
345	ei->flags = ALLOC_FAT_CHAIN;
346	ei->type = TYPE_DIR;
347	ei->version = 0;
348	ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
349	ei->hint_stat.eidx = 0;
350	ei->hint_stat.clu = sbi->root_dir;
351	ei->hint_femp.eidx = EXFAT_HINT_NONE;
352
353	exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
354	if (exfat_count_num_clusters(sb, &cdir, &num_clu))
355		return -EIO;
356	i_size_write(inode, num_clu << sbi->cluster_size_bits);
357
358	num_subdirs = exfat_count_dir_entries(sb, &cdir);
359	if (num_subdirs < 0)
360		return -EIO;
361	set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR);
362
363	inode->i_uid = sbi->options.fs_uid;
364	inode->i_gid = sbi->options.fs_gid;
365	inode_inc_iversion(inode);
366	inode->i_generation = 0;
367	inode->i_mode = exfat_make_mode(sbi, EXFAT_ATTR_SUBDIR, 0777);
368	inode->i_op = &exfat_dir_inode_operations;
369	inode->i_fop = &exfat_dir_operations;
370
371	inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9;
372	ei->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff;
373	ei->i_size_aligned = i_size_read(inode);
374	ei->i_size_ondisk = i_size_read(inode);
375
376	exfat_save_attr(inode, EXFAT_ATTR_SUBDIR);
377	ei->i_crtime = simple_inode_init_ts(inode);
378	exfat_truncate_inode_atime(inode);
379	return 0;
380}
381
382static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect)
383{
384	struct exfat_sb_info *sbi = EXFAT_SB(sb);
385
386	if (!is_power_of_2(logical_sect)) {
387		exfat_err(sb, "bogus logical sector size %u", logical_sect);
388		return -EIO;
389	}
390
391	if (logical_sect < sb->s_blocksize) {
392		exfat_err(sb, "logical sector size too small for device (logical sector size = %u)",
393			  logical_sect);
394		return -EIO;
395	}
396
397	if (logical_sect > sb->s_blocksize) {
398		brelse(sbi->boot_bh);
399		sbi->boot_bh = NULL;
400
401		if (!sb_set_blocksize(sb, logical_sect)) {
402			exfat_err(sb, "unable to set blocksize %u",
403				  logical_sect);
404			return -EIO;
405		}
406		sbi->boot_bh = sb_bread(sb, 0);
407		if (!sbi->boot_bh) {
408			exfat_err(sb, "unable to read boot sector (logical sector size = %lu)",
409				  sb->s_blocksize);
410			return -EIO;
411		}
412	}
413	return 0;
414}
415
416static int exfat_read_boot_sector(struct super_block *sb)
417{
418	struct boot_sector *p_boot;
419	struct exfat_sb_info *sbi = EXFAT_SB(sb);
420
421	/* set block size to read super block */
422	sb_min_blocksize(sb, 512);
423
424	/* read boot sector */
425	sbi->boot_bh = sb_bread(sb, 0);
426	if (!sbi->boot_bh) {
427		exfat_err(sb, "unable to read boot sector");
428		return -EIO;
429	}
430	p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
431
432	/* check the validity of BOOT */
433	if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {
434		exfat_err(sb, "invalid boot record signature");
435		return -EINVAL;
436	}
437
438	if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) {
439		exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */
440		return -EINVAL;
441	}
442
443	/*
444	 * must_be_zero field must be filled with zero to prevent mounting
445	 * from FAT volume.
446	 */
447	if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero)))
448		return -EINVAL;
449
450	if (p_boot->num_fats != 1 && p_boot->num_fats != 2) {
451		exfat_err(sb, "bogus number of FAT structure");
452		return -EINVAL;
453	}
454
455	/*
456	 * sect_size_bits could be at least 9 and at most 12.
457	 */
458	if (p_boot->sect_size_bits < EXFAT_MIN_SECT_SIZE_BITS ||
459	    p_boot->sect_size_bits > EXFAT_MAX_SECT_SIZE_BITS) {
460		exfat_err(sb, "bogus sector size bits : %u",
461				p_boot->sect_size_bits);
462		return -EINVAL;
463	}
464
465	/*
466	 * sect_per_clus_bits could be at least 0 and at most 25 - sect_size_bits.
467	 */
468	if (p_boot->sect_per_clus_bits > EXFAT_MAX_SECT_PER_CLUS_BITS(p_boot)) {
469		exfat_err(sb, "bogus sectors bits per cluster : %u",
470				p_boot->sect_per_clus_bits);
471		return -EINVAL;
472	}
473
474	sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits;
475	sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits;
476	sbi->cluster_size_bits = p_boot->sect_per_clus_bits +
477		p_boot->sect_size_bits;
478	sbi->cluster_size = 1 << sbi->cluster_size_bits;
479	sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length);
480	sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset);
481	sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset);
482	if (p_boot->num_fats == 2)
483		sbi->FAT2_start_sector += sbi->num_FAT_sectors;
484	sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset);
485	sbi->num_sectors = le64_to_cpu(p_boot->vol_length);
486	/* because the cluster index starts with 2 */
487	sbi->num_clusters = le32_to_cpu(p_boot->clu_count) +
488		EXFAT_RESERVED_CLUSTERS;
489
490	sbi->root_dir = le32_to_cpu(p_boot->root_cluster);
491	sbi->dentries_per_clu = 1 <<
492		(sbi->cluster_size_bits - DENTRY_SIZE_BITS);
493
494	sbi->vol_flags = le16_to_cpu(p_boot->vol_flags);
495	sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE);
496	sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
497	sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;
498
499	/* check consistencies */
500	if ((u64)sbi->num_FAT_sectors << p_boot->sect_size_bits <
501	    (u64)sbi->num_clusters * 4) {
502		exfat_err(sb, "bogus fat length");
503		return -EINVAL;
504	}
505
506	if (sbi->data_start_sector <
507	    (u64)sbi->FAT1_start_sector +
508	    (u64)sbi->num_FAT_sectors * p_boot->num_fats) {
509		exfat_err(sb, "bogus data start sector");
510		return -EINVAL;
511	}
512
513	if (sbi->vol_flags & VOLUME_DIRTY)
514		exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");
515	if (sbi->vol_flags & MEDIA_FAILURE)
516		exfat_warn(sb, "Medium has reported failures. Some data may be lost.");
517
518	/* exFAT file size is limited by a disk volume size */
519	sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) <<
520		sbi->cluster_size_bits;
521
522	/* check logical sector size */
523	if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits))
524		return -EIO;
525
526	return 0;
527}
528
529static int exfat_verify_boot_region(struct super_block *sb)
530{
531	struct buffer_head *bh = NULL;
532	u32 chksum = 0;
533	__le32 *p_sig, *p_chksum;
534	int sn, i;
535
536	/* read boot sector sub-regions */
537	for (sn = 0; sn < 11; sn++) {
538		bh = sb_bread(sb, sn);
539		if (!bh)
540			return -EIO;
541
542		if (sn != 0 && sn <= 8) {
543			/* extended boot sector sub-regions */
544			p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4];
545			if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE)
546				exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x",
547					   sn, le32_to_cpu(*p_sig));
548		}
549
550		chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize,
551			chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR);
552		brelse(bh);
553	}
554
555	/* boot checksum sub-regions */
556	bh = sb_bread(sb, sn);
557	if (!bh)
558		return -EIO;
559
560	for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) {
561		p_chksum = (__le32 *)&bh->b_data[i];
562		if (le32_to_cpu(*p_chksum) != chksum) {
563			exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)",
564				  le32_to_cpu(*p_chksum), chksum);
565			brelse(bh);
566			return -EINVAL;
567		}
568	}
569	brelse(bh);
570	return 0;
571}
572
573/* mount the file system volume */
574static int __exfat_fill_super(struct super_block *sb)
575{
576	int ret;
577	struct exfat_sb_info *sbi = EXFAT_SB(sb);
578
579	ret = exfat_read_boot_sector(sb);
580	if (ret) {
581		exfat_err(sb, "failed to read boot sector");
582		goto free_bh;
583	}
584
585	ret = exfat_verify_boot_region(sb);
586	if (ret) {
587		exfat_err(sb, "invalid boot region");
588		goto free_bh;
589	}
590
591	ret = exfat_create_upcase_table(sb);
592	if (ret) {
593		exfat_err(sb, "failed to load upcase table");
594		goto free_bh;
595	}
596
597	ret = exfat_load_bitmap(sb);
598	if (ret) {
599		exfat_err(sb, "failed to load alloc-bitmap");
600		goto free_bh;
601	}
602
603	ret = exfat_count_used_clusters(sb, &sbi->used_clusters);
604	if (ret) {
605		exfat_err(sb, "failed to scan clusters");
606		goto free_alloc_bitmap;
607	}
608
609	return 0;
610
611free_alloc_bitmap:
612	exfat_free_bitmap(sbi);
613free_bh:
614	brelse(sbi->boot_bh);
615	return ret;
616}
617
618static int exfat_fill_super(struct super_block *sb, struct fs_context *fc)
619{
620	struct exfat_sb_info *sbi = sb->s_fs_info;
621	struct exfat_mount_options *opts = &sbi->options;
622	struct inode *root_inode;
623	int err;
624
625	if (opts->allow_utime == (unsigned short)-1)
626		opts->allow_utime = ~opts->fs_dmask & 0022;
627
628	if (opts->discard && !bdev_max_discard_sectors(sb->s_bdev)) {
629		exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard");
630		opts->discard = 0;
631	}
632
633	sb->s_flags |= SB_NODIRATIME;
634	sb->s_magic = EXFAT_SUPER_MAGIC;
635	sb->s_op = &exfat_sops;
636
637	sb->s_time_gran = 10 * NSEC_PER_MSEC;
638	sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS;
639	sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS;
640
641	err = __exfat_fill_super(sb);
642	if (err) {
643		exfat_err(sb, "failed to recognize exfat type");
644		goto check_nls_io;
645	}
646
647	/* set up enough so that it can read an inode */
648	exfat_hash_init(sb);
649
650	if (!strcmp(sbi->options.iocharset, "utf8"))
651		opts->utf8 = 1;
652	else {
653		sbi->nls_io = load_nls(sbi->options.iocharset);
654		if (!sbi->nls_io) {
655			exfat_err(sb, "IO charset %s not found",
656				  sbi->options.iocharset);
657			err = -EINVAL;
658			goto free_table;
659		}
660	}
661
662	if (sbi->options.utf8)
663		sb->s_d_op = &exfat_utf8_dentry_ops;
664	else
665		sb->s_d_op = &exfat_dentry_ops;
666
667	root_inode = new_inode(sb);
668	if (!root_inode) {
669		exfat_err(sb, "failed to allocate root inode");
670		err = -ENOMEM;
671		goto free_table;
672	}
673
674	root_inode->i_ino = EXFAT_ROOT_INO;
675	inode_set_iversion(root_inode, 1);
676	err = exfat_read_root(root_inode);
677	if (err) {
678		exfat_err(sb, "failed to initialize root inode");
679		goto put_inode;
680	}
681
682	exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos);
683	insert_inode_hash(root_inode);
684
685	sb->s_root = d_make_root(root_inode);
686	if (!sb->s_root) {
687		exfat_err(sb, "failed to get the root dentry");
688		err = -ENOMEM;
689		goto free_table;
690	}
691
692	return 0;
693
694put_inode:
695	iput(root_inode);
696	sb->s_root = NULL;
697
698free_table:
699	exfat_free_bitmap(sbi);
700	brelse(sbi->boot_bh);
701
702check_nls_io:
703	return err;
704}
705
706static int exfat_get_tree(struct fs_context *fc)
707{
708	return get_tree_bdev(fc, exfat_fill_super);
709}
710
711static void exfat_free_sbi(struct exfat_sb_info *sbi)
712{
713	exfat_free_iocharset(sbi);
714	kfree(sbi);
715}
716
717static void exfat_free(struct fs_context *fc)
718{
719	struct exfat_sb_info *sbi = fc->s_fs_info;
720
721	if (sbi)
722		exfat_free_sbi(sbi);
723}
724
725static int exfat_reconfigure(struct fs_context *fc)
726{
727	fc->sb_flags |= SB_NODIRATIME;
728
729	/* volume flag will be updated in exfat_sync_fs */
730	sync_filesystem(fc->root->d_sb);
731	return 0;
732}
733
734static const struct fs_context_operations exfat_context_ops = {
735	.parse_param	= exfat_parse_param,
736	.get_tree	= exfat_get_tree,
737	.free		= exfat_free,
738	.reconfigure	= exfat_reconfigure,
739};
740
741static int exfat_init_fs_context(struct fs_context *fc)
742{
743	struct exfat_sb_info *sbi;
744
745	sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL);
746	if (!sbi)
747		return -ENOMEM;
748
749	mutex_init(&sbi->s_lock);
750	mutex_init(&sbi->bitmap_lock);
751	ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
752			DEFAULT_RATELIMIT_BURST);
753
754	sbi->options.fs_uid = current_uid();
755	sbi->options.fs_gid = current_gid();
756	sbi->options.fs_fmask = current->fs->umask;
757	sbi->options.fs_dmask = current->fs->umask;
758	sbi->options.allow_utime = -1;
759	sbi->options.iocharset = exfat_default_iocharset;
760	sbi->options.errors = EXFAT_ERRORS_RO;
761
762	fc->s_fs_info = sbi;
763	fc->ops = &exfat_context_ops;
764	return 0;
765}
766
767static void delayed_free(struct rcu_head *p)
768{
769	struct exfat_sb_info *sbi = container_of(p, struct exfat_sb_info, rcu);
770
771	unload_nls(sbi->nls_io);
772	exfat_free_upcase_table(sbi);
773	exfat_free_sbi(sbi);
774}
775
776static void exfat_kill_sb(struct super_block *sb)
777{
778	struct exfat_sb_info *sbi = sb->s_fs_info;
779
780	kill_block_super(sb);
781	if (sbi)
782		call_rcu(&sbi->rcu, delayed_free);
783}
784
785static struct file_system_type exfat_fs_type = {
786	.owner			= THIS_MODULE,
787	.name			= "exfat",
788	.init_fs_context	= exfat_init_fs_context,
789	.parameters		= exfat_parameters,
790	.kill_sb		= exfat_kill_sb,
791	.fs_flags		= FS_REQUIRES_DEV,
792};
793
794static void exfat_inode_init_once(void *foo)
795{
796	struct exfat_inode_info *ei = (struct exfat_inode_info *)foo;
797
798	spin_lock_init(&ei->cache_lru_lock);
799	ei->nr_caches = 0;
800	ei->cache_valid_id = EXFAT_CACHE_VALID + 1;
801	INIT_LIST_HEAD(&ei->cache_lru);
802	INIT_HLIST_NODE(&ei->i_hash_fat);
803	inode_init_once(&ei->vfs_inode);
804}
805
806static int __init init_exfat_fs(void)
807{
808	int err;
809
810	err = exfat_cache_init();
811	if (err)
812		return err;
813
814	exfat_inode_cachep = kmem_cache_create("exfat_inode_cache",
815			sizeof(struct exfat_inode_info),
816			0, SLAB_RECLAIM_ACCOUNT,
817			exfat_inode_init_once);
818	if (!exfat_inode_cachep) {
819		err = -ENOMEM;
820		goto shutdown_cache;
821	}
822
823	err = register_filesystem(&exfat_fs_type);
824	if (err)
825		goto destroy_cache;
826
827	return 0;
828
829destroy_cache:
830	kmem_cache_destroy(exfat_inode_cachep);
831shutdown_cache:
832	exfat_cache_shutdown();
833	return err;
834}
835
836static void __exit exit_exfat_fs(void)
837{
838	/*
839	 * Make sure all delayed rcu free inodes are flushed before we
840	 * destroy cache.
841	 */
842	rcu_barrier();
843	kmem_cache_destroy(exfat_inode_cachep);
844	unregister_filesystem(&exfat_fs_type);
845	exfat_cache_shutdown();
846}
847
848module_init(init_exfat_fs);
849module_exit(exit_exfat_fs);
850
851MODULE_ALIAS_FS("exfat");
852MODULE_LICENSE("GPL");
853MODULE_DESCRIPTION("exFAT filesystem support");
854MODULE_AUTHOR("Samsung Electronics Co., Ltd.");
855