btrfs-progs: correct prompt of minimal num of devs for raid56

For btrfs,
Raid5 can't go below 2 devs, not 3;
Raid6 can't go below 3 devs, not 4.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/ioctl.h b/ioctl.h
index 402317f..9627e8d 100644 (file)
--- a/ioctl.h
+++ b/ioctl.h
@@ -480,9 +480,9 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code)
                case BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET:
                        return "unable to go below four devices on raid10";
                case BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET:
-                       return "unable to go below three devices on raid5";
+                       return "unable to go below two devices on raid5";
                case BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET:
-                       return "unable to go below four devices on raid6";
+                       return "unable to go below three devices on raid6";
                case BTRFS_ERROR_DEV_TGT_REPLACE:
                        return "unable to remove the dev_replace target dev";
                case BTRFS_ERROR_DEV_MISSING_NOT_FOUND: