X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=lib%2Fdiskimage_lvm2.ml;h=4432e90e845d4f3d2a19eac9d6c99c7594e7a9f3;hb=e1e5cfb926e886b8fc3126429d045b8ba305fe50;hp=ea127cb3972afbfb97507f2af98585fe20738342;hpb=382e1b9e7a33ad25389b1ed98aa4e854880491d9;p=virt-df.git

diff --git a/lib/diskimage_lvm2.ml b/lib/diskimage_lvm2.ml
index ea127cb..4432e90 100644
--- a/lib/diskimage_lvm2.ml
+++ b/lib/diskimage_lvm2.ml
@@ -64,22 +64,39 @@ object (self)
    *)
   method blocksize = extent_size
 
-  (* Map block (extent) i to the underlying device. *)
-  method mapblock i =
+  method private map i =
     if i < ~^0 || i >= size_in_extents then
       invalid_arg "linear_map_device: read outside device";
 
     let rec loop = function
       | [] ->
-	  []
+	  None
       | (start_extent, end_extent, dev, pvoffset) :: rest ->
-	  if start_extent <= i && i < end_extent then
-	    [dev, (pvoffset +^ i) *^ extent_size]
-	  else
+	  if start_extent <= i && i < end_extent then (
+	    let dev_offset = (pvoffset +^ i) *^ extent_size in
+	    Some (start_extent, end_extent, dev, dev_offset, pvoffset)
+	  ) else
 	    loop rest
     in
     loop segments
 
+  (* Map block (extent) i to the underlying device. *)
+  method map_block i =
+    match self#map i with
+    | Some (_, _, dev, dev_offset, _) -> [dev, dev_offset]
+    | None -> []
+
+  (* Continguous span. *)
+  method contiguous offset =
+    let offset_in_extents = offset /^ extent_size in
+
+    (* Get the segment that this offset lies in. *)
+    match self#map offset_in_extents with
+    | Some (_, end_extent, dev, dev_offset, _) ->
+	(* Contiguous bytes up to the end of this extent. *)
+	end_extent *^ extent_size -^ offset
+    | None -> ~^0
+
   (* NB. Use the superclass #read method. *)
 end