md-bitmap: use %pD to print the file name in md_bitmap_file_kick

Don't bother allocating an extra buffer in the I/O failure handler and
instead use the printk built-in format to print the last 4 path name
components.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230615064840.629492-4-hch@lst.de

drivers/md/md-bitmap.c

@@ -870,21 +870,13 @@ static void md_bitmap_file_unmap(struct bitmap_storage *store)
  */
 static void md_bitmap_file_kick(struct bitmap *bitmap)
 {
-	char *path, *ptr = NULL;
-
 	if (!test_and_set_bit(BITMAP_STALE, &bitmap->flags)) {
 		md_bitmap_update_sb(bitmap);
 
 		if (bitmap->storage.file) {
-			path = kmalloc(PAGE_SIZE, GFP_KERNEL);
-			if (path)
-				ptr = file_path(bitmap->storage.file,
-					     path, PAGE_SIZE);
-
-			pr_warn("%s: kicking failed bitmap file %s from array!\n",
-				bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
+			pr_warn("%s: kicking failed bitmap file %pD4 from array!\n",
+				bmname(bitmap), bitmap->storage.file);
 
-			kfree(path);
 		} else
 			pr_warn("%s: disabling internal bitmap due to errors\n",
 				bmname(bitmap));