btrfs-progs: balance: add stripes filter

Add new balance filter 'stripes=<range>' to process only chunks that are
spread accross given number of chunks.

The range minimum and maximum are inclusive.

Signed-off-by: Gabríel Arthúr Pétursson <gabriel@system.is>
[ reworked a bit to use the range helpers, dropped the single value
  for stripes ]
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/ioctl.h b/ioctl.h
index e5cf3230..0df2444c 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -239,7 +239,9 @@ struct btrfs_balance_args {
 			__u32 limit_max;
 		};
 	};
-	__u64 unused[7];
+	__u32 stripes_min;
+	__u32 stripes_max;
+	__u64 unused[6];
 } __attribute__ ((__packed__));
 
 /* report balance progress to userspace */