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9#include <linux/module.h>
10#include <linux/fs.h>
11#include <linux/buffer_head.h>
12#include <linux/time.h>
13#include "fat.h"
14
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21
22
23void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
24{
25 struct fat_mount_options *opts = &MSDOS_SB(sb)->options;
26 va_list args;
27 struct va_format vaf;
28
29 if (report) {
30 va_start(args, fmt);
31 vaf.fmt = fmt;
32 vaf.va = &args;
33 fat_msg(sb, KERN_ERR, "error, %pV", &vaf);
34 va_end(args);
35 }
36
37 if (opts->errors == FAT_ERRORS_PANIC)
38 panic("FAT-fs (%s): fs panic from previous error\n", sb->s_id);
39 else if (opts->errors == FAT_ERRORS_RO && !(sb->s_flags & MS_RDONLY)) {
40 sb->s_flags |= MS_RDONLY;
41 fat_msg(sb, KERN_ERR, "Filesystem has been set read-only");
42 }
43}
44EXPORT_SYMBOL_GPL(__fat_fs_error);
45
46
47
48
49
50void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...)
51{
52 struct va_format vaf;
53 va_list args;
54
55 va_start(args, fmt);
56 vaf.fmt = fmt;
57 vaf.va = &args;
58 printk("%sFAT-fs (%s): %pV\n", level, sb->s_id, &vaf);
59 va_end(args);
60}
61
62
63
64int fat_clusters_flush(struct super_block *sb)
65{
66 struct msdos_sb_info *sbi = MSDOS_SB(sb);
67 struct buffer_head *bh;
68 struct fat_boot_fsinfo *fsinfo;
69
70 if (sbi->fat_bits != 32)
71 return 0;
72
73 bh = sb_bread(sb, sbi->fsinfo_sector);
74 if (bh == NULL) {
75 fat_msg(sb, KERN_ERR, "bread failed in fat_clusters_flush");
76 return -EIO;
77 }
78
79 fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
80
81 if (!IS_FSINFO(fsinfo)) {
82 fat_msg(sb, KERN_ERR, "Invalid FSINFO signature: "
83 "0x%08x, 0x%08x (sector = %lu)",
84 le32_to_cpu(fsinfo->signature1),
85 le32_to_cpu(fsinfo->signature2),
86 sbi->fsinfo_sector);
87 } else {
88 if (sbi->free_clusters != -1)
89 fsinfo->free_clusters = cpu_to_le32(sbi->free_clusters);
90 if (sbi->prev_free != -1)
91 fsinfo->next_cluster = cpu_to_le32(sbi->prev_free);
92 mark_buffer_dirty(bh);
93 }
94 brelse(bh);
95
96 return 0;
97}
98
99
100
101
102
103int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
104{
105 struct super_block *sb = inode->i_sb;
106 struct msdos_sb_info *sbi = MSDOS_SB(sb);
107 int ret, new_fclus, last;
108
109
110
111
112
113 last = new_fclus = 0;
114 if (MSDOS_I(inode)->i_start) {
115 int fclus, dclus;
116
117 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
118 if (ret < 0)
119 return ret;
120 new_fclus = fclus + 1;
121 last = dclus;
122 }
123
124
125 if (last) {
126 struct fat_entry fatent;
127
128 fatent_init(&fatent);
129 ret = fat_ent_read(inode, &fatent, last);
130 if (ret >= 0) {
131 int wait = inode_needs_sync(inode);
132 ret = fat_ent_write(inode, &fatent, new_dclus, wait);
133 fatent_brelse(&fatent);
134 }
135 if (ret < 0)
136 return ret;
137
138
139
140
141
142 } else {
143 MSDOS_I(inode)->i_start = new_dclus;
144 MSDOS_I(inode)->i_logstart = new_dclus;
145
146
147
148
149 if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) {
150 ret = fat_sync_inode(inode);
151 if (ret)
152 return ret;
153 } else
154 mark_inode_dirty(inode);
155 }
156 if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
157 fat_fs_error(sb, "clusters badly computed (%d != %llu)",
158 new_fclus,
159 (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
160 fat_cache_inval_inode(inode);
161 }
162 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
163
164 return 0;
165}
166
167extern struct timezone sys_tz;
168
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177
178
179#define SECS_PER_MIN 60
180#define SECS_PER_HOUR (60 * 60)
181#define SECS_PER_DAY (SECS_PER_HOUR * 24)
182
183#define DAYS_DELTA (365 * 10 + 2)
184
185#define YEAR_2100 120
186#define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100)
187
188
189static time_t days_in_year[] = {
190
191 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
192};
193
194
195void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
196 __le16 __time, __le16 __date, u8 time_cs)
197{
198 u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
199 time_t second, day, leap_day, month, year;
200
201 year = date >> 9;
202 month = max(1, (date >> 5) & 0xf);
203 day = max(1, date & 0x1f) - 1;
204
205 leap_day = (year + 3) / 4;
206 if (year > YEAR_2100)
207 leap_day--;
208 if (IS_LEAP_YEAR(year) && month > 2)
209 leap_day++;
210
211 second = (time & 0x1f) << 1;
212 second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
213 second += (time >> 11) * SECS_PER_HOUR;
214 second += (year * 365 + leap_day
215 + days_in_year[month] + day
216 + DAYS_DELTA) * SECS_PER_DAY;
217
218 if (!sbi->options.tz_set)
219 second += sys_tz.tz_minuteswest * SECS_PER_MIN;
220 else
221 second -= sbi->options.time_offset * SECS_PER_MIN;
222
223 if (time_cs) {
224 ts->tv_sec = second + (time_cs / 100);
225 ts->tv_nsec = (time_cs % 100) * 10000000;
226 } else {
227 ts->tv_sec = second;
228 ts->tv_nsec = 0;
229 }
230}
231
232
233void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
234 __le16 *time, __le16 *date, u8 *time_cs)
235{
236 struct tm tm;
237 time_to_tm(ts->tv_sec,
238 (sbi->options.tz_set ? sbi->options.time_offset :
239 -sys_tz.tz_minuteswest) * SECS_PER_MIN, &tm);
240
241
242 if (tm.tm_year < 1980 - 1900) {
243 *time = 0;
244 *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
245 if (time_cs)
246 *time_cs = 0;
247 return;
248 }
249 if (tm.tm_year > 2107 - 1900) {
250 *time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
251 *date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
252 if (time_cs)
253 *time_cs = 199;
254 return;
255 }
256
257
258 tm.tm_year -= 80;
259
260 tm.tm_mon++;
261
262 tm.tm_sec >>= 1;
263
264 *time = cpu_to_le16(tm.tm_hour << 11 | tm.tm_min << 5 | tm.tm_sec);
265 *date = cpu_to_le16(tm.tm_year << 9 | tm.tm_mon << 5 | tm.tm_mday);
266 if (time_cs)
267 *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
268}
269EXPORT_SYMBOL_GPL(fat_time_unix2fat);
270
271int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
272{
273 int i, err = 0;
274
275 for (i = 0; i < nr_bhs; i++)
276 write_dirty_buffer(bhs[i], WRITE);
277
278 for (i = 0; i < nr_bhs; i++) {
279 wait_on_buffer(bhs[i]);
280 if (!err && !buffer_uptodate(bhs[i]))
281 err = -EIO;
282 }
283 return err;
284}
285