fs/ntfs: use timespec64 directly for timestamp conversion

Now that the VFS has been converted from timespec to timespec64
timestamps, only the conversion to/from ntfs timestamps uses 32-bit
seconds.

This changes that last missing piece to get the ntfs implementation
y2038 safe on 32-bit architectures.

Link: http://lkml.kernel.org/r/20180718115017.742609-2-arnd@arndb.deSigned-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ntfs/inode.c

@@ -667,18 +667,18 @@ static int ntfs_read_locked_inode(struct inode *vi)
 	 * mtime is the last change of the data within the file. Not changed
 	 * when only metadata is changed, e.g. a rename doesn't affect mtime.
 	 */
-	vi->i_mtime = timespec_to_timespec64(ntfs2utc(si->last_data_change_time));
+	vi->i_mtime = ntfs2utc(si->last_data_change_time);
 	/*
 	 * ctime is the last change of the metadata of the file. This obviously
 	 * always changes, when mtime is changed. ctime can be changed on its
 	 * own, mtime is then not changed, e.g. when a file is renamed.
 	 */
-	vi->i_ctime = timespec_to_timespec64(ntfs2utc(si->last_mft_change_time));
+	vi->i_ctime = ntfs2utc(si->last_mft_change_time);
 	/*
 	 * Last access to the data within the file. Not changed during a rename
 	 * for example but changed whenever the file is written to.
 	 */
-	vi->i_atime = timespec_to_timespec64(ntfs2utc(si->last_access_time));
+	vi->i_atime = ntfs2utc(si->last_access_time);
 
 	/* Find the attribute list attribute if present. */
 	ntfs_attr_reinit_search_ctx(ctx);
@@ -2997,7 +2997,7 @@ int __ntfs_write_inode(struct inode *vi, int sync)
 	si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
 			le16_to_cpu(ctx->attr->data.resident.value_offset));
 	/* Update the access times if they have changed. */
-	nt = utc2ntfs(timespec64_to_timespec(vi->i_mtime));
+	nt = utc2ntfs(vi->i_mtime);
 	if (si->last_data_change_time != nt) {
 		ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
 				"new = 0x%llx", vi->i_ino, (long long)
@@ -3006,7 +3006,7 @@ int __ntfs_write_inode(struct inode *vi, int sync)
 		si->last_data_change_time = nt;
 		modified = true;
 	}
-	nt = utc2ntfs(timespec64_to_timespec(vi->i_ctime));
+	nt = utc2ntfs(vi->i_ctime);
 	if (si->last_mft_change_time != nt) {
 		ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
 				"new = 0x%llx", vi->i_ino, (long long)
@@ -3015,7 +3015,7 @@ int __ntfs_write_inode(struct inode *vi, int sync)
 		si->last_mft_change_time = nt;
 		modified = true;
 	}
-	nt = utc2ntfs(timespec64_to_timespec(vi->i_atime));
+	nt = utc2ntfs(vi->i_atime);
 	if (si->last_access_time != nt) {
 		ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
 				"new = 0x%llx", vi->i_ino,

fs/ntfs/time.h

@@ -36,16 +36,16 @@
  * Convert the Linux UTC time @ts to its corresponding NTFS time and return
  * that in little endian format.
  *
- * Linux stores time in a struct timespec consisting of a time_t (long at
- * present) tv_sec and a long tv_nsec where tv_sec is the number of 1-second
- * intervals since 1st January 1970, 00:00:00 UTC and tv_nsec is the number of
- * 1-nano-second intervals since the value of tv_sec.
+ * Linux stores time in a struct timespec64 consisting of a time64_t tv_sec
+ * and a long tv_nsec where tv_sec is the number of 1-second intervals since
+ * 1st January 1970, 00:00:00 UTC and tv_nsec is the number of 1-nano-second
+ * intervals since the value of tv_sec.
  *
  * NTFS uses Microsoft's standard time format which is stored in a s64 and is
  * measured as the number of 100-nano-second intervals since 1st January 1601,
  * 00:00:00 UTC.
  */
-static inline sle64 utc2ntfs(const struct timespec ts)
+static inline sle64 utc2ntfs(const struct timespec64 ts)
 {
 	/*
 	 * Convert the seconds to 100ns intervals, add the nano-seconds
@@ -63,7 +63,10 @@ static inline sle64 utc2ntfs(const struct timespec ts)
  */
 static inline sle64 get_current_ntfs_time(void)
 {
-	return utc2ntfs(current_kernel_time());
+	struct timespec64 ts;
+
+	ktime_get_coarse_real_ts64(&ts);
+	return utc2ntfs(ts);
 }
 
 /**
@@ -73,18 +76,18 @@ static inline sle64 get_current_ntfs_time(void)
  * Convert the little endian NTFS time @time to its corresponding Linux UTC
  * time and return that in cpu format.
  *
- * Linux stores time in a struct timespec consisting of a time_t (long at
- * present) tv_sec and a long tv_nsec where tv_sec is the number of 1-second
- * intervals since 1st January 1970, 00:00:00 UTC and tv_nsec is the number of
- * 1-nano-second intervals since the value of tv_sec.
+ * Linux stores time in a struct timespec64 consisting of a time64_t tv_sec
+ * and a long tv_nsec where tv_sec is the number of 1-second intervals since
+ * 1st January 1970, 00:00:00 UTC and tv_nsec is the number of 1-nano-second
+ * intervals since the value of tv_sec.
  *
  * NTFS uses Microsoft's standard time format which is stored in a s64 and is
  * measured as the number of 100 nano-second intervals since 1st January 1601,
  * 00:00:00 UTC.
  */
-static inline struct timespec ntfs2utc(const sle64 time)
+static inline struct timespec64 ntfs2utc(const sle64 time)
 {
-	struct timespec ts;
+	struct timespec64 ts;
 
 	/* Subtract the NTFS time offset. */
 	u64 t = (u64)(sle64_to_cpu(time) - NTFS_TIME_OFFSET);