[patch] Patch that will apply to gentoo-sources-2.6.26 (or .25)

gentoo-sources-2.6.26-fat-utc-option.patch (text/plain), 7.59 KB, created by Joe Peterson (RETIRED) on 2008-07-29 18:43:35 UTC

New mount option ("tz=UTC") for FAT (vfat/msdos) filesystems allowing
timestamps to be in coordinated universal time (UTC) rather than
local time in applications where doing this is advantageous (like
digital cameras, etc.)

Signed-off-by: Joe Peterson <[e-mail]>
Acked-by: OGAWA Hirofumi <[e-mail]>
---

diff -puNr a/fs/fat/dir.c b/fs/fat/dir.c
--- a/fs/fat/dir.c	2008-06-25 08:53:35.676901351 -0600
+++ b/fs/fat/dir.c	2008-06-26 12:58:56.096272279 -0600
@@ -1082,7 +1082,7 @@ int fat_alloc_new_dir(struct inode *dir,
 		goto error_free;
 	}
 
-	fat_date_unix2dos(ts->tv_sec, &time, &date);
+	fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
 
 	de = (struct msdos_dir_entry *)bhs[0]->b_data;
 	/* filling the new directory slots ("." and ".." entries) */
diff -puNr a/fs/fat/inode.c b/fs/fat/inode.c
--- a/fs/fat/inode.c	2008-06-25 08:53:35.676901351 -0600
+++ b/fs/fat/inode.c	2008-06-26 14:57:07.087942764 -0600
@@ -382,17 +382,20 @@ static int fat_fill_inode(struct inode *
 	inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
 			   & ~((loff_t)sbi->cluster_size - 1)) >> 9;
 	inode->i_mtime.tv_sec =
-		date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date));
+		date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date),
+			      sbi->options.tz_utc);
 	inode->i_mtime.tv_nsec = 0;
 	if (sbi->options.isvfat) {
 		int secs = de->ctime_cs / 100;
 		int csecs = de->ctime_cs % 100;
 		inode->i_ctime.tv_sec  =
 			date_dos2unix(le16_to_cpu(de->ctime),
-				      le16_to_cpu(de->cdate)) + secs;
+				      le16_to_cpu(de->cdate),
+				      sbi->options.tz_utc) + secs;
 		inode->i_ctime.tv_nsec = csecs * 10000000;
 		inode->i_atime.tv_sec =
-			date_dos2unix(0, le16_to_cpu(de->adate));
+			date_dos2unix(0, le16_to_cpu(de->adate),
+				      sbi->options.tz_utc);
 		inode->i_atime.tv_nsec = 0;
 	} else
 		inode->i_ctime = inode->i_atime = inode->i_mtime;
@@ -592,11 +595,14 @@ retry:
 	raw_entry->attr = fat_attr(inode);
 	raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
 	raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
-	fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time, &raw_entry->date);
+	fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time,
+			  &raw_entry->date, sbi->options.tz_utc);
 	if (sbi->options.isvfat) {
 		__le16 atime;
-		fat_date_unix2dos(inode->i_ctime.tv_sec,&raw_entry->ctime,&raw_entry->cdate);
-		fat_date_unix2dos(inode->i_atime.tv_sec,&atime,&raw_entry->adate);
+		fat_date_unix2dos(inode->i_ctime.tv_sec, &raw_entry->ctime,
+				  &raw_entry->cdate, sbi->options.tz_utc);
+		fat_date_unix2dos(inode->i_atime.tv_sec, &atime,
+				  &raw_entry->adate, sbi->options.tz_utc);
 		raw_entry->ctime_cs = (inode->i_ctime.tv_sec & 1) * 100 +
 			inode->i_ctime.tv_nsec / 10000000;
 	}
@@ -836,6 +842,8 @@ static int fat_show_options(struct seq_f
 	}
 	if (sbi->options.flush)
 		seq_puts(m, ",flush");
+	if (opts->tz_utc)
+		seq_puts(m, ",tz=UTC");
 
 	return 0;
 }
@@ -848,7 +856,7 @@ enum {
 	Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
 	Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
 	Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
-	Opt_obsolate, Opt_flush, Opt_err,
+	Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_err,
 };
 
 static match_table_t fat_tokens = {
@@ -883,6 +891,7 @@ static match_table_t fat_tokens = {
 	{Opt_obsolate, "cvf_options=%100s"},
 	{Opt_obsolate, "posix"},
 	{Opt_flush, "flush"},
+	{Opt_tz_utc, "tz=UTC"},
 	{Opt_err, NULL},
 };
 static match_table_t msdos_tokens = {
@@ -947,6 +956,7 @@ static int parse_options(char *options, 
 	opts->utf8 = opts->unicode_xlate = 0;
 	opts->numtail = 1;
 	opts->usefree = opts->nocase = 0;
+	opts->tz_utc = 0;
 	*debug = 0;
 
 	if (!options)
@@ -1036,6 +1046,9 @@ static int parse_options(char *options, 
 		case Opt_flush:
 			opts->flush = 1;
 			break;
+		case Opt_tz_utc:
+			opts->tz_utc = 1;
+			break;
 
 		/* msdos specific */
 		case Opt_dots:
diff -puNr a/fs/fat/misc.c b/fs/fat/misc.c
--- a/fs/fat/misc.c	2008-06-25 08:53:35.676901351 -0600
+++ b/fs/fat/misc.c	2008-06-26 12:59:08.627376422 -0600
@@ -142,7 +142,7 @@ static int day_n[] = {
 };
 
 /* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */
-int date_dos2unix(unsigned short time, unsigned short date)
+int date_dos2unix(unsigned short time, unsigned short date, int tz_utc)
 {
 	int month, year, secs;
 
@@ -156,16 +156,18 @@ int date_dos2unix(unsigned short time, u
 	    ((date & 31)-1+day_n[month]+(year/4)+year*365-((year & 3) == 0 &&
 	    month < 2 ? 1 : 0)+3653);
 			/* days since 1.1.70 plus 80's leap day */
-	secs += sys_tz.tz_minuteswest*60;
+	if (!tz_utc)
+		secs += sys_tz.tz_minuteswest*60;
 	return secs;
 }
 
 /* Convert linear UNIX date to a MS-DOS time/date pair. */
-void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date)
+void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, int tz_utc)
 {
 	int day, year, nl_day, month;
 
-	unix_date -= sys_tz.tz_minuteswest*60;
+	if (!tz_utc)
+		unix_date -= sys_tz.tz_minuteswest*60;
 
 	/* Jan 1 GMT 00:00:00 1980. But what about another time zone? */
 	if (unix_date < 315532800)
diff -puNr a/fs/msdos/namei.c b/fs/msdos/namei.c
--- a/fs/msdos/namei.c	2008-06-25 08:53:35.696902410 -0600
+++ b/fs/msdos/namei.c	2008-06-26 12:58:42.255055811 -0600
@@ -243,6 +243,7 @@ static int msdos_add_entry(struct inode 
 			   int is_dir, int is_hid, int cluster,
 			   struct timespec *ts, struct fat_slot_info *sinfo)
 {
+	struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
 	struct msdos_dir_entry de;
 	__le16 time, date;
 	int err;
@@ -252,7 +253,7 @@ static int msdos_add_entry(struct inode 
 	if (is_hid)
 		de.attr |= ATTR_HIDDEN;
 	de.lcase = 0;
-	fat_date_unix2dos(ts->tv_sec, &time, &date);
+	fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
 	de.cdate = de.adate = 0;
 	de.ctime = 0;
 	de.ctime_cs = 0;
diff -puNr a/fs/vfat/namei.c b/fs/vfat/namei.c
--- a/fs/vfat/namei.c	2008-06-25 08:53:35.686902663 -0600
+++ b/fs/vfat/namei.c	2008-06-26 12:58:27.073724049 -0600
@@ -621,7 +621,7 @@ shortname:
 	memcpy(de->name, msdos_name, MSDOS_NAME);
 	de->attr = is_dir ? ATTR_DIR : ATTR_ARCH;
 	de->lcase = lcase;
-	fat_date_unix2dos(ts->tv_sec, &time, &date);
+	fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
 	de->time = de->ctime = time;
 	de->date = de->cdate = de->adate = date;
 	de->ctime_cs = 0;
diff -puNr a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h
--- a/include/linux/msdos_fs.h	2008-06-25 08:53:17.435303045 -0600
+++ b/include/linux/msdos_fs.h	2008-06-26 14:58:40.626135522 -0600
@@ -205,7 +205,8 @@ struct fat_mount_options {
 		 atari:1,         /* Use Atari GEMDOS variation of MS-DOS fs */
 		 flush:1,	  /* write things quickly */
 		 nocase:1,	  /* Does this need case conversion? 0=need case conversion*/
-		 usefree:1;	  /* Use free_clusters for FAT32 */
+		 usefree:1,	  /* Use free_clusters for FAT32 */
+		 tz_utc:1;	  /* Filesystem timestamps are in UTC */
 };
 
 #define FAT_HASH_BITS	8
@@ -428,8 +429,9 @@ extern int fat_flush_inodes(struct super
 extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
 extern void fat_clusters_flush(struct super_block *sb);
 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
-extern int date_dos2unix(unsigned short time, unsigned short date);
-extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date);
+extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc);
+extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date,
+			      int tz_utc);
 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
 
 int fat_cache_init(void);