fat: introduce mark_fsinfo_dirty helper

A preparation patch which introduces a 'mark_fsinfo_dirty()' helper
function which just sets the 's_dirt' flag to 1 so far. I'll add more
code to this helper later, so I do not mark it as 'inline'.

Signed-off-by: Artem Bityutskiy <[e-mail]>
Cc: OGAWA Hirofumi <[e-mail]>
Cc: Al Viro <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/fat/fatent.c

···
 	}
 }
 
+static void mark_fsinfo_dirty(struct super_block *sb)
+{
+	sb->s_dirt = 1;
+}
+
 static inline int fat_ent_update_ptr(struct super_block *sb,
 				     struct fat_entry *fatent,
 				     int offset, sector_t blocknr)
···
 				sbi->prev_free = entry;
 				if (sbi->free_clusters != -1)
 					sbi->free_clusters--;
-				sb->s_dirt = 1;
+				mark_fsinfo_dirty(sb);
 
 				cluster[idx_clus] = entry;
 				idx_clus++;
···
 	/* Couldn't allocate the free entries */
 	sbi->free_clusters = 0;
 	sbi->free_clus_valid = 1;
-	sb->s_dirt = 1;
+	mark_fsinfo_dirty(sb);
 	err = -ENOSPC;
 
 out:
···
 		ops->ent_put(&fatent, FAT_ENT_FREE);
 		if (sbi->free_clusters != -1) {
 			sbi->free_clusters++;
-			sb->s_dirt = 1;
+			mark_fsinfo_dirty(sb);
 		}
 
 		if (nr_bhs + fatent.nr_bhs > MAX_BUF_PER_PAGE) {
···
 	}
 	sbi->free_clusters = free;
 	sbi->free_clus_valid = 1;
-	sb->s_dirt = 1;
+	mark_fsinfo_dirty(sb);
 	fatent_brelse(&fatent);
 out:
 	unlock_fat(sbi);