From: Richard W.M. Jones <"Richard W.M. Jones "> Date: Tue, 15 Apr 2008 14:27:06 +0000 (+0100) Subject: Read out the actual metadata. X-Git-Tag: 1.0.4~24^2~21 X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=b25ac692bd7107b56850de8fa25123791dfdf73e;p=virt-top.git Read out the actual metadata. --- diff --git a/virt-df/virt_df_lvm2.ml b/virt-df/virt_df_lvm2.ml index abc247e..afcab66 100644 --- a/virt-df/virt_df_lvm2.ml +++ b/virt-df/virt_df_lvm2.ml @@ -32,12 +32,13 @@ let sector_size64 = 512L (* Probe to see if it's an LVM2 PV. Look for the "LABELONE" label. *) let rec probe_pv lvm_plugin_id dev = try - let uuid, metadata_offset, metadata_length = read_pv_label dev in + let uuid, _ = read_pv_label dev in if debug then - eprintf "LVM2 detected UUID %s md offset 0x%lx len %ld\n%!" - uuid metadata_offset metadata_length; + eprintf "LVM2 detected PV UUID %s\n%!" uuid; { lvm_plugin_id = lvm_plugin_id; pv_uuid = uuid } - with _ -> raise Not_found + with exn -> + if debug then prerr_endline (Printexc.to_string exn); + raise Not_found and read_pv_label dev = (* Load the first 8 sectors. I found by experimentation that @@ -47,7 +48,7 @@ and read_pv_label dev = *) let bits = dev#read_bitstring 0L (9 * sector_size) in - Bitmatch.hexdump_bitstring stdout bits; + (*Bitmatch.hexdump_bitstring stdout bits;*) bitmatch bits with | sector0 : sector_size*8 : bitstring; (* sector 0 *) @@ -64,26 +65,36 @@ and read_pv_label dev = when Bitmatch.string_of_bitstring labelone = "LABELONE" && Bitmatch.string_of_bitstring lvm2_ver = "LVM2 001" -> let metadata_offset = metadata_offset +* 0x1000_l in + let metadata = read_metadata dev metadata_offset metadata_length in + (*prerr_endline metadata;*) + let uuid = Bitmatch.string_of_bitstring uuid in - (* Check the metadata offset & length look reasonable for this - * device. Otherwise maybe it's a newer or older header which - * we don't really understand properly. - *) - let () = - let size = - if dev#size <= Int64.of_int32 Int32.max_int then Int64.to_int32 dev#size - else Int32.max_int in - if metadata_offset < 0x1200_l || metadata_offset >= size - || metadata_length < 0_l || metadata_offset+*metadata_length >= size - then - invalid_arg "read_pv_label: bad metadata offset or length" in - - Bitmatch.string_of_bitstring uuid, metadata_offset, metadata_length - + uuid, metadata | _ -> - invalid_arg (sprintf "read_pv_label: %s: not an LVM2 physical volume" - dev#name) + invalid_arg + (sprintf "LVM2: read_pv_label: %s: not an LVM2 physical volume" dev#name) + +and read_metadata dev offset32 len32 = + if debug then + eprintf "metadata: offset 0x%lx len %ld bytes\n" offset32 len32; + + (* Check the offset and length are sensible. *) + let offset64 = + if offset32 <= Int32.max_int then Int64.of_int32 offset32 + else invalid_arg "LVM2: read_metadata: metadata offset too large" in + let len64 = + if len32 <= 2_147_483_647_l then Int64.of_int32 len32 + else invalid_arg "LVM2: read_metadata: metadata length too large" in + + if offset64 <= 0x1200L || offset64 >= dev#size + || len64 <= 0L || offset64 +^ len64 >= dev#size then + invalid_arg "LVM2: read_metadata: bad metadata offset or length"; + + (* If it is outside the disk boundaries, this will throw an exception, + * otherwise it will read and return the metadata string. + *) + dev#read offset64 (Int64.to_int len64) (* We are passed a list of devices which we previously identified * as PVs belonging to us. From these produce a list of all LVs