[Libguestfs] [PATCH 3/3] resize: copy GPT partition flags

[Cédric Bosdonnat]

In some cases, the first stage bootloader needs the 'Legacy BIOS
bootable' flag to be set on the partition. This change copies all
flags (including this one) for each partition of the old disk to the
new one to avoid ending up with non-bootable disks.
---
 resize/resize.ml | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/resize/resize.ml b/resize/resize.ml
index 880fa98cb..4328d162e 100644
--- a/resize/resize.ml
+++ b/resize/resize.ml
@@ -50,6 +50,7 @@ type partition = {
   p_type : partition_content;    (* Content type and content size. *)
   p_label : string option;       (* Label/name. *)
   p_guid : string option;        (* Partition GUID (GPT only). *)
+  p_attributes : string option;  (* Partition attributes hex bit mask (GPT only). *)
 
   (* What we're going to do: *)
   mutable p_operation : partition_operation;
@@ -493,6 +494,12 @@ read the man page virt-resize(1).
           let label =
             try Some (g#part_get_name "/dev/sda" part_num)
             with G.Error _ -> None in
+          let attributes =
+            match parttype with
+            | MBR -> None
+            | GPT ->
+              try Some (g#part_get_gpt_attributes "/dev/sda" part_num)
+              with G.Error _ -> None in
           let guid =
             match parttype with
             | MBR -> None
@@ -502,7 +509,7 @@ read the man page virt-resize(1).
 
           { p_name = name; p_part = part;
             p_bootable = bootable; p_id = id; p_type = typ;
-            p_label = label; p_guid = guid;
+            p_label = label; p_guid = guid; p_attributes = attributes;
             p_operation = OpCopy; p_target_partnum = 0;
             p_target_start = 0L; p_target_end = 0L }
       ) parts in
@@ -1150,6 +1157,7 @@ read the man page virt-resize(1).
                      part_size = 0L };
           p_bootable = false; p_id = No_ID; p_type = ContentUnknown;
           p_label = None; p_guid = None;
+          p_attributes = None;
 
           (* Target information is meaningful. *)
           p_operation = OpIgnore;
@@ -1191,12 +1199,13 @@ read the man page virt-resize(1).
    * is changed from primary to extended.  Thus we need to set the
    * MBR ID before doing the copy so sfdisk doesn't corrupt things.
    *)
-  let set_partition_bootable_and_id p =
+  let set_partition_bootable_attributes_and_id p =
       if p.p_bootable then
         g#part_set_bootable "/dev/sdb" p.p_target_partnum true;
 
       Option.may (g#part_set_name "/dev/sdb" p.p_target_partnum) p.p_label;
       Option.may (g#part_set_gpt_guid "/dev/sdb" p.p_target_partnum) p.p_guid;
+      Option.may (g#part_set_gpt_attributes "/dev/sdb" p.p_target_partnum) p.p_attributes;
 
       match parttype, p.p_id with
       | GPT, GPT_Type gpt_type ->
@@ -1205,7 +1214,7 @@ read the man page virt-resize(1).
         g#part_set_mbr_id "/dev/sdb" p.p_target_partnum mbr_id
       | GPT, (No_ID|MBR_ID _) | MBR, (No_ID|GPT_Type _) -> ()
   in
-  List.iter set_partition_bootable_and_id partitions;
+  List.iter set_partition_bootable_attributes_and_id partitions;
 
   (* Copy over the data. *)
   let copy_partition p =
-- 
2.15.1