Mention minimum size on devices that are considered too small

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

diff --git a/utils.c b/utils.c
index 8f49c7a..a87c5a8 100644 (file)
--- a/utils.c
+++ b/utils.c
@@ -531,7 +531,8 @@ int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret)
        zero_end = 1;
 
        if (block_count < 256 * 1024 * 1024) {
-               fprintf(stderr, "device %s is too small\n", file);
+               fprintf(stderr, "device %s is too small "
+                       "(must be at least 256 MB)\n", file);
                exit(1);
        }
        ret = zero_dev_start(fd);