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authorJames Morris <jmorris@namei.org>2008-11-13 19:29:12 -0500
committerJames Morris <jmorris@namei.org>2008-11-13 19:29:12 -0500
commit2b828925652340277a889cbc11b2d0637f7cdaf7 (patch)
tree32fcb3d3e466fc419fad2d3717956a5b5ad3d35a /fs/fat/misc.c
parent3a3b7ce9336952ea7b9564d976d068a238976c9d (diff)
parent58e20d8d344b0ee083febb18c2b021d2427e56ca (diff)
Merge branch 'master' into next
Conflicts: security/keys/internal.h security/keys/process_keys.c security/keys/request_key.c Fixed conflicts above by using the non 'tsk' versions. Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'fs/fat/misc.c')
-rw-r--r--fs/fat/misc.c155
1 files changed, 111 insertions, 44 deletions
diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index 79fb98ad36d4..ac39ebcc1496 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -8,8 +8,8 @@
8 8
9#include <linux/module.h> 9#include <linux/module.h>
10#include <linux/fs.h> 10#include <linux/fs.h>
11#include <linux/msdos_fs.h>
12#include <linux/buffer_head.h> 11#include <linux/buffer_head.h>
12#include "fat.h"
13 13
14/* 14/*
15 * fat_fs_panic reports a severe file system problem and sets the file system 15 * fat_fs_panic reports a severe file system problem and sets the file system
@@ -124,8 +124,9 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
124 mark_inode_dirty(inode); 124 mark_inode_dirty(inode);
125 } 125 }
126 if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) { 126 if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
127 fat_fs_panic(sb, "clusters badly computed (%d != %lu)", 127 fat_fs_panic(sb, "clusters badly computed (%d != %llu)",
128 new_fclus, inode->i_blocks >> (sbi->cluster_bits - 9)); 128 new_fclus,
129 (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
129 fat_cache_inval_inode(inode); 130 fat_cache_inval_inode(inode);
130 } 131 }
131 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9); 132 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
@@ -135,65 +136,131 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
135 136
136extern struct timezone sys_tz; 137extern struct timezone sys_tz;
137 138
139/*
140 * The epoch of FAT timestamp is 1980.
141 * : bits : value
142 * date: 0 - 4: day (1 - 31)
143 * date: 5 - 8: month (1 - 12)
144 * date: 9 - 15: year (0 - 127) from 1980
145 * time: 0 - 4: sec (0 - 29) 2sec counts
146 * time: 5 - 10: min (0 - 59)
147 * time: 11 - 15: hour (0 - 23)
148 */
149#define SECS_PER_MIN 60
150#define SECS_PER_HOUR (60 * 60)
151#define SECS_PER_DAY (SECS_PER_HOUR * 24)
152#define UNIX_SECS_1980 315532800L
153#if BITS_PER_LONG == 64
154#define UNIX_SECS_2108 4354819200L
155#endif
156/* days between 1.1.70 and 1.1.80 (2 leap days) */
157#define DAYS_DELTA (365 * 10 + 2)
158/* 120 (2100 - 1980) isn't leap year */
159#define YEAR_2100 120
160#define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100)
161
138/* Linear day numbers of the respective 1sts in non-leap years. */ 162/* Linear day numbers of the respective 1sts in non-leap years. */
139static int day_n[] = { 163static time_t days_in_year[] = {
140 /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */ 164 /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */
141 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0, 0 165 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
142}; 166};
143 167
144/* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */ 168/* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */
145int date_dos2unix(unsigned short time, unsigned short date, int tz_utc) 169void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
170 __le16 __time, __le16 __date, u8 time_cs)
146{ 171{
147 int month, year, secs; 172 u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
173 time_t second, day, leap_day, month, year;
148 174
149 /* 175 year = date >> 9;
150 * first subtract and mask after that... Otherwise, if 176 month = max(1, (date >> 5) & 0xf);
151 * date == 0, bad things happen 177 day = max(1, date & 0x1f) - 1;
152 */ 178
153 month = ((date >> 5) - 1) & 15; 179 leap_day = (year + 3) / 4;
154 year = date >> 9; 180 if (year > YEAR_2100) /* 2100 isn't leap year */
155 secs = (time & 31)*2+60*((time >> 5) & 63)+(time >> 11)*3600+86400* 181 leap_day--;
156 ((date & 31)-1+day_n[month]+(year/4)+year*365-((year & 3) == 0 && 182 if (IS_LEAP_YEAR(year) && month > 2)
157 month < 2 ? 1 : 0)+3653); 183 leap_day++;
158 /* days since 1.1.70 plus 80's leap day */ 184
159 if (!tz_utc) 185 second = (time & 0x1f) << 1;
160 secs += sys_tz.tz_minuteswest*60; 186 second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
161 return secs; 187 second += (time >> 11) * SECS_PER_HOUR;
188 second += (year * 365 + leap_day
189 + days_in_year[month] + day
190 + DAYS_DELTA) * SECS_PER_DAY;
191
192 if (!sbi->options.tz_utc)
193 second += sys_tz.tz_minuteswest * SECS_PER_MIN;
194
195 if (time_cs) {
196 ts->tv_sec = second + (time_cs / 100);
197 ts->tv_nsec = (time_cs % 100) * 10000000;
198 } else {
199 ts->tv_sec = second;
200 ts->tv_nsec = 0;
201 }
162} 202}
163 203
164/* Convert linear UNIX date to a MS-DOS time/date pair. */ 204/* Convert linear UNIX date to a FAT time/date pair. */
165void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, int tz_utc) 205void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
206 __le16 *time, __le16 *date, u8 *time_cs)
166{ 207{
167 int day, year, nl_day, month; 208 time_t second = ts->tv_sec;
209 time_t day, leap_day, month, year;
168 210
169 if (!tz_utc) 211 if (!sbi->options.tz_utc)
170 unix_date -= sys_tz.tz_minuteswest*60; 212 second -= sys_tz.tz_minuteswest * SECS_PER_MIN;
171 213
172 /* Jan 1 GMT 00:00:00 1980. But what about another time zone? */ 214 /* Jan 1 GMT 00:00:00 1980. But what about another time zone? */
173 if (unix_date < 315532800) 215 if (second < UNIX_SECS_1980) {
174 unix_date = 315532800; 216 *time = 0;
175 217 *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
176 *time = cpu_to_le16((unix_date % 60)/2+(((unix_date/60) % 60) << 5)+ 218 if (time_cs)
177 (((unix_date/3600) % 24) << 11)); 219 *time_cs = 0;
178 day = unix_date/86400-3652; 220 return;
179 year = day/365; 221 }
180 if ((year+3)/4+365*year > day) 222#if BITS_PER_LONG == 64
223 if (second >= UNIX_SECS_2108) {
224 *time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
225 *date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
226 if (time_cs)
227 *time_cs = 199;
228 return;
229 }
230#endif
231
232 day = second / SECS_PER_DAY - DAYS_DELTA;
233 year = day / 365;
234 leap_day = (year + 3) / 4;
235 if (year > YEAR_2100) /* 2100 isn't leap year */
236 leap_day--;
237 if (year * 365 + leap_day > day)
181 year--; 238 year--;
182 day -= (year+3)/4+365*year; 239 leap_day = (year + 3) / 4;
183 if (day == 59 && !(year & 3)) { 240 if (year > YEAR_2100) /* 2100 isn't leap year */
184 nl_day = day; 241 leap_day--;
242 day -= year * 365 + leap_day;
243
244 if (IS_LEAP_YEAR(year) && day == days_in_year[3]) {
185 month = 2; 245 month = 2;
186 } else { 246 } else {
187 nl_day = (year & 3) || day <= 59 ? day : day-1; 247 if (IS_LEAP_YEAR(year) && day > days_in_year[3])
188 for (month = 0; month < 12; month++) { 248 day--;
189 if (day_n[month] > nl_day) 249 for (month = 1; month < 12; month++) {
250 if (days_in_year[month + 1] > day)
190 break; 251 break;
191 } 252 }
192 } 253 }
193 *date = cpu_to_le16(nl_day-day_n[month-1]+1+(month << 5)+(year << 9)); 254 day -= days_in_year[month];
194}
195 255
196EXPORT_SYMBOL_GPL(fat_date_unix2dos); 256 *time = cpu_to_le16(((second / SECS_PER_HOUR) % 24) << 11
257 | ((second / SECS_PER_MIN) % 60) << 5
258 | (second % SECS_PER_MIN) >> 1);
259 *date = cpu_to_le16((year << 9) | (month << 5) | (day + 1));
260 if (time_cs)
261 *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
262}
263EXPORT_SYMBOL_GPL(fat_time_unix2fat);
197 264
198int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs) 265int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
199{ 266{