btrfs-progs: mkfs: Use the whole file or block device to mkfs for rootdir

For --rootdir, even for large existing file or block device, it will
always shrink the resulting filesystem.

The problem is, mkfs.btrfs will try to calculate the dir size, and use
it as @block_count to mkfs, which makes the filesystem shrunk.

Fix it by trying to get the original block device or file size as
@block_count, so mkfs.btrfs can use the full file/block device for
--rootdir option.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/utils.h b/utils.h
index 860c25d3..bd7484fd 100644
--- a/utils.h
+++ b/utils.h
@@ -123,6 +123,7 @@ char *__strncpy_null(char *dest, const char *src, size_t n);
 int is_block_device(const char *file);
 int is_mount_point(const char *file);
 int is_path_exist(const char *file);
+int is_reg_file(const char *path);
 int check_arg_type(const char *input);
 int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose);
 int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only);