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9#include <linux/module.h>
10#include <linux/fs.h>
11#include <linux/buffer_head.h>
12#include "fat.h"
13
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21
22void fat_fs_error(struct super_block *s, const char *fmt, ...)
23{
24 struct fat_mount_options *opts = &MSDOS_SB(s)->options;
25 va_list args;
26
27 printk(KERN_ERR "FAT: Filesystem error (dev %s)\n", s->s_id);
28
29 printk(KERN_ERR " ");
30 va_start(args, fmt);
31 vprintk(fmt, args);
32 va_end(args);
33 printk("\n");
34
35 if (opts->errors == FAT_ERRORS_PANIC)
36 panic(" FAT fs panic from previous error\n");
37 else if (opts->errors == FAT_ERRORS_RO && !(s->s_flags & MS_RDONLY)) {
38 s->s_flags |= MS_RDONLY;
39 printk(KERN_ERR " File system has been set read-only\n");
40 }
41}
42EXPORT_SYMBOL_GPL(fat_fs_error);
43
44
45
46int fat_clusters_flush(struct super_block *sb)
47{
48 struct msdos_sb_info *sbi = MSDOS_SB(sb);
49 struct buffer_head *bh;
50 struct fat_boot_fsinfo *fsinfo;
51
52 if (sbi->fat_bits != 32)
53 return 0;
54
55 bh = sb_bread(sb, sbi->fsinfo_sector);
56 if (bh == NULL) {
57 printk(KERN_ERR "FAT: bread failed in fat_clusters_flush\n");
58 return -EIO;
59 }
60
61 fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
62
63 if (!IS_FSINFO(fsinfo)) {
64 printk(KERN_ERR "FAT: Invalid FSINFO signature: "
65 "0x%08x, 0x%08x (sector = %lu)\n",
66 le32_to_cpu(fsinfo->signature1),
67 le32_to_cpu(fsinfo->signature2),
68 sbi->fsinfo_sector);
69 } else {
70 if (sbi->free_clusters != -1)
71 fsinfo->free_clusters = cpu_to_le32(sbi->free_clusters);
72 if (sbi->prev_free != -1)
73 fsinfo->next_cluster = cpu_to_le32(sbi->prev_free);
74 mark_buffer_dirty(bh);
75 }
76 brelse(bh);
77
78 return 0;
79}
80
81
82
83
84
85int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
86{
87 struct super_block *sb = inode->i_sb;
88 struct msdos_sb_info *sbi = MSDOS_SB(sb);
89 int ret, new_fclus, last;
90
91
92
93
94
95 last = new_fclus = 0;
96 if (MSDOS_I(inode)->i_start) {
97 int fclus, dclus;
98
99 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
100 if (ret < 0)
101 return ret;
102 new_fclus = fclus + 1;
103 last = dclus;
104 }
105
106
107 if (last) {
108 struct fat_entry fatent;
109
110 fatent_init(&fatent);
111 ret = fat_ent_read(inode, &fatent, last);
112 if (ret >= 0) {
113 int wait = inode_needs_sync(inode);
114 ret = fat_ent_write(inode, &fatent, new_dclus, wait);
115 fatent_brelse(&fatent);
116 }
117 if (ret < 0)
118 return ret;
119
120 } else {
121 MSDOS_I(inode)->i_start = new_dclus;
122 MSDOS_I(inode)->i_logstart = new_dclus;
123
124
125
126
127 if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) {
128 ret = fat_sync_inode(inode);
129 if (ret)
130 return ret;
131 } else
132 mark_inode_dirty(inode);
133 }
134 if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
135 fat_fs_error(sb, "clusters badly computed (%d != %llu)",
136 new_fclus,
137 (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
138 fat_cache_inval_inode(inode);
139 }
140 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
141
142 return 0;
143}
144
145extern struct timezone sys_tz;
146
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156
157#define SECS_PER_MIN 60
158#define SECS_PER_HOUR (60 * 60)
159#define SECS_PER_DAY (SECS_PER_HOUR * 24)
160#define UNIX_SECS_1980 315532800L
161#if BITS_PER_LONG == 64
162#define UNIX_SECS_2108 4354819200L
163#endif
164
165#define DAYS_DELTA (365 * 10 + 2)
166
167#define YEAR_2100 120
168#define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100)
169
170
171static time_t days_in_year[] = {
172
173 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
174};
175
176
177void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
178 __le16 __time, __le16 __date, u8 time_cs)
179{
180 u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
181 time_t second, day, leap_day, month, year;
182
183 year = date >> 9;
184 month = max(1, (date >> 5) & 0xf);
185 day = max(1, date & 0x1f) - 1;
186
187 leap_day = (year + 3) / 4;
188 if (year > YEAR_2100)
189 leap_day--;
190 if (IS_LEAP_YEAR(year) && month > 2)
191 leap_day++;
192
193 second = (time & 0x1f) << 1;
194 second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
195 second += (time >> 11) * SECS_PER_HOUR;
196 second += (year * 365 + leap_day
197 + days_in_year[month] + day
198 + DAYS_DELTA) * SECS_PER_DAY;
199
200 if (!sbi->options.tz_utc)
201 second += sys_tz.tz_minuteswest * SECS_PER_MIN;
202
203 if (time_cs) {
204 ts->tv_sec = second + (time_cs / 100);
205 ts->tv_nsec = (time_cs % 100) * 10000000;
206 } else {
207 ts->tv_sec = second;
208 ts->tv_nsec = 0;
209 }
210}
211
212
213void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
214 __le16 *time, __le16 *date, u8 *time_cs)
215{
216 time_t second = ts->tv_sec;
217 time_t day, leap_day, month, year;
218
219 if (!sbi->options.tz_utc)
220 second -= sys_tz.tz_minuteswest * SECS_PER_MIN;
221
222
223 if (second < UNIX_SECS_1980) {
224 *time = 0;
225 *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
226 if (time_cs)
227 *time_cs = 0;
228 return;
229 }
230#if BITS_PER_LONG == 64
231 if (second >= UNIX_SECS_2108) {
232 *time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
233 *date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
234 if (time_cs)
235 *time_cs = 199;
236 return;
237 }
238#endif
239
240 day = second / SECS_PER_DAY - DAYS_DELTA;
241 year = day / 365;
242 leap_day = (year + 3) / 4;
243 if (year > YEAR_2100)
244 leap_day--;
245 if (year * 365 + leap_day > day)
246 year--;
247 leap_day = (year + 3) / 4;
248 if (year > YEAR_2100)
249 leap_day--;
250 day -= year * 365 + leap_day;
251
252 if (IS_LEAP_YEAR(year) && day == days_in_year[3]) {
253 month = 2;
254 } else {
255 if (IS_LEAP_YEAR(year) && day > days_in_year[3])
256 day--;
257 for (month = 1; month < 12; month++) {
258 if (days_in_year[month + 1] > day)
259 break;
260 }
261 }
262 day -= days_in_year[month];
263
264 *time = cpu_to_le16(((second / SECS_PER_HOUR) % 24) << 11
265 | ((second / SECS_PER_MIN) % 60) << 5
266 | (second % SECS_PER_MIN) >> 1);
267 *date = cpu_to_le16((year << 9) | (month << 5) | (day + 1));
268 if (time_cs)
269 *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
270}
271EXPORT_SYMBOL_GPL(fat_time_unix2fat);
272
273int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
274{
275 int i, err = 0;
276
277 ll_rw_block(SWRITE, nr_bhs, bhs);
278 for (i = 0; i < nr_bhs; i++) {
279 wait_on_buffer(bhs[i]);
280 if (buffer_eopnotsupp(bhs[i])) {
281 clear_buffer_eopnotsupp(bhs[i]);
282 err = -EOPNOTSUPP;
283 } else if (!err && !buffer_uptodate(bhs[i]))
284 err = -EIO;
285 }
286 return err;
287}
288
289