fs: allow error returns from generic_update_time

Now that no caller looks at the updated flags, switch generic_update_time
to the same calling convention as the ->update_time method and return 0
or a negative errno.

This prepares for adding non-blocking timestamp updates that could return
-EAGAIN.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260108141934.2052404-3-hch@lst.de
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/gfs2/inode.c

@@ -2257,8 +2257,7 @@ static int gfs2_update_time(struct inode *inode, int flags)
 		if (error)
 			return error;
 	}
-	generic_update_time(inode, flags);
-	return 0;
+	return generic_update_time(inode, flags);
 }
 
 static const struct inode_operations gfs2_file_iops = {

fs/inode.c

@@ -2141,7 +2141,7 @@ EXPORT_SYMBOL(inode_update_timestamps);
  * or S_VERSION need to be updated we attempt to update all three of them. S_ATIME
  * updates can be handled done independently of the rest.
  *
- * Returns a S_* mask indicating which fields were updated.
+ * Returns a negative error value on error, else 0.
  */
 int generic_update_time(struct inode *inode, int flags)
 {
@@ -2153,7 +2153,7 @@ int generic_update_time(struct inode *inode, int flags)
 	if (updated & S_VERSION)
 		dirty_flags |= I_DIRTY_SYNC;
 	__mark_inode_dirty(inode, dirty_flags);
-	return updated;
+	return 0;
 }
 EXPORT_SYMBOL(generic_update_time);
 

fs/ubifs/file.c

@@ -1379,10 +1379,8 @@ int ubifs_update_time(struct inode *inode, int flags)
 			.dirtied_ino_d = ALIGN(ui->data_len, 8) };
 	int err, release;
 
-	if (!IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT)) {
-		generic_update_time(inode, flags);
-		return 0;
-	}
+	if (!IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT))
+		return generic_update_time(inode, flags);
 
 	err = ubifs_budget_space(c, &req);
 	if (err)

fs/xfs/xfs_iops.c

@@ -1197,10 +1197,8 @@ xfs_vn_update_time(
 
 	if (inode->i_sb->s_flags & SB_LAZYTIME) {
 		if (!((flags & S_VERSION) &&
-		      inode_maybe_inc_iversion(inode, false))) {
-			generic_update_time(inode, flags);
-			return 0;
-		}
+		      inode_maybe_inc_iversion(inode, false)))
+			return generic_update_time(inode, flags);
 
 		/* Capture the iversion update that just occurred */
 		log_flags |= XFS_ILOG_CORE;

include/linux/fs.h

@@ -2399,7 +2399,7 @@ extern void ihold(struct inode * inode);
 extern void iput(struct inode *);
 void iput_not_last(struct inode *);
 int inode_update_timestamps(struct inode *inode, int flags);
-int generic_update_time(struct inode *, int);
+int generic_update_time(struct inode *inode, int flags);
 
 /* /sys/fs */
 extern struct kobject *fs_kobj;