(* virt-resize
* Copyright (C) 2010-2011 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*)
open Printf
module G = Guestfs
open Utils
(* Minimum surplus before we create an extra partition. *)
let min_extra_partition = 10L *^ 1024L *^ 1024L
(* Command line argument parsing. *)
let prog = Filename.basename Sys.executable_name
type align_first_t = [ `Never | `Always | `Auto ]
let infile, outfile, align_first, alignment, copy_boot_loader,
debug, debug_gc, deletes,
dryrun, expand, expand_content, extra_partition, format, ignores,
lv_expands, machine_readable, ntfsresize_force, output_format,
quiet, resizes, resizes_force, shrink =
let display_version () =
let g = new G.guestfs () in
let version = g#version () in
printf "virt-resize %Ld.%Ld.%Ld%s\n"
version.G.major version.G.minor version.G.release version.G.extra;
exit 0
in
let add xs s = xs := s :: !xs in
let align_first = ref "auto" in
let alignment = ref 128 in
let copy_boot_loader = ref true in
let debug = ref false in
let debug_gc = ref false in
let deletes = ref [] in
let dryrun = ref false in
let expand = ref "" in
let set_expand s =
if s = "" then error "%s: empty --expand option" prog
else if !expand <> "" then error "--expand option given twice"
else expand := s
in
let expand_content = ref true in
let extra_partition = ref true in
let format = ref "" in
let ignores = ref [] in
let lv_expands = ref [] in
let machine_readable = ref false in
let ntfsresize_force = ref false in
let output_format = ref "" in
let quiet = ref false in
let resizes = ref [] in
let resizes_force = ref [] in
let shrink = ref "" in
let set_shrink s =
if s = "" then error "empty --shrink option"
else if !shrink <> "" then error "--shrink option given twice"
else shrink := s
in
let argspec = Arg.align [
"--align-first", Arg.Set_string align_first, "never|always|auto Align first partition (default: auto)";
"--alignment", Arg.Set_int alignment, "sectors Set partition alignment (default: 128 sectors)";
"--no-copy-boot-loader", Arg.Clear copy_boot_loader, " Don't copy boot loader";
"-d", Arg.Set debug, " Enable debugging messages";
"--debug", Arg.Set debug, " -\"-";
"--debug-gc",Arg.Set debug_gc, " Debug GC and memory allocations";
"--delete", Arg.String (add deletes), "part Delete partition";
"--expand", Arg.String set_expand, "part Expand partition";
"--no-expand-content", Arg.Clear expand_content, " Don't expand content";
"--no-extra-partition", Arg.Clear extra_partition, " Don't create extra partition";
"--format", Arg.Set_string format, "format Format of input disk";
"--ignore", Arg.String (add ignores), "part Ignore partition";
"--lv-expand", Arg.String (add lv_expands), "lv Expand logical volume";
"--LV-expand", Arg.String (add lv_expands), "lv -\"-";
"--lvexpand", Arg.String (add lv_expands), "lv -\"-";
"--LVexpand", Arg.String (add lv_expands), "lv -\"-";
"--machine-readable", Arg.Set machine_readable, " Make output machine readable";
"-n", Arg.Set dryrun, " Don't perform changes";
"--dryrun", Arg.Set dryrun, " -\"-";
"--dry-run", Arg.Set dryrun, " -\"-";
"--ntfsresize-force", Arg.Set ntfsresize_force, " Force ntfsresize";
"--output-format", Arg.Set_string format, "format Format of output disk";
"-q", Arg.Set quiet, " Don't print the summary";
"--quiet", Arg.Set quiet, " -\"-";
"--resize", Arg.String (add resizes), "part=size Resize partition";
"--resize-force", Arg.String (add resizes_force), "part=size Forcefully resize partition";
"--shrink", Arg.String set_shrink, "part Shrink partition";
"-V", Arg.Unit display_version, " Display version and exit";
"--version", Arg.Unit display_version, " -\"-";
] in
let disks = ref [] in
let anon_fun s = disks := s :: !disks in
let usage_msg =
sprintf "\
%s: resize a virtual machine disk
A short summary of the options is given below. For detailed help please
read the man page virt-resize(1).
"
prog in
Arg.parse argspec anon_fun usage_msg;
let debug = !debug in
if debug then (
eprintf "command line:";
List.iter (eprintf " %s") (Array.to_list Sys.argv);
prerr_newline ()
);
(* Dereference the rest of the args. *)
let alignment = !alignment in
let copy_boot_loader = !copy_boot_loader in
let debug_gc = !debug_gc in
let deletes = List.rev !deletes in
let dryrun = !dryrun in
let expand = match !expand with "" -> None | str -> Some str in
let expand_content = !expand_content in
let extra_partition = !extra_partition in
let format = match !format with "" -> None | str -> Some str in
let ignores = List.rev !ignores in
let lv_expands = List.rev !lv_expands in
let machine_readable = !machine_readable in
let ntfsresize_force = !ntfsresize_force in
let output_format = match !output_format with "" -> None | str -> Some str in
let quiet = !quiet in
let resizes = List.rev !resizes in
let resizes_force = List.rev !resizes_force in
let shrink = match !shrink with "" -> None | str -> Some str in
if alignment < 1 then
error "alignment cannot be < 1";
let alignment = Int64.of_int alignment in
let align_first =
match !align_first with
| "never" -> `Never
| "always" -> `Always
| "auto" -> `Auto
| _ ->
error "unknown --align-first option: use never|always|auto" in
(* No arguments and machine-readable mode? Print out some facts
* about what this binary supports. We only need to print out new
* things added since this option, or things which depend on features
* of the appliance.
*)
if !disks = [] && machine_readable then (
printf "virt-resize\n";
printf "ntfsresize-force\n";
printf "32bitok\n";
printf "128-sector-alignment\n";
printf "alignment\n";
printf "align-first\n";
let g = new G.guestfs () in
g#add_drive_opts "/dev/null";
g#launch ();
if feature_available g [| "ntfsprogs"; "ntfs3g" |] then
printf "ntfs\n";
if feature_available g [| "btrfs" |] then
printf "btrfs\n";
exit 0
);
(* Verify we got exactly 2 disks. *)
let infile, outfile =
match List.rev !disks with
| [infile; outfile] -> infile, outfile
| _ ->
error "usage is: %s [--options] indisk outdisk" prog in
infile, outfile, align_first, alignment, copy_boot_loader,
debug, debug_gc, deletes,
dryrun, expand, expand_content, extra_partition, format, ignores,
lv_expands, machine_readable, ntfsresize_force, output_format,
quiet, resizes, resizes_force, shrink
(* Default to true, since NTFS and btrfs support are usually available. *)
let ntfs_available = ref true
let btrfs_available = ref true
(* Add in and out disks to the handle and launch. *)
let connect_both_disks () =
let g = new G.guestfs () in
if debug then g#set_trace true;
g#add_drive_opts ?format ~readonly:true infile;
g#add_drive_opts ?format:output_format ~readonly:false outfile;
if not quiet then Progress.set_up_progress_bar ~machine_readable g;
g#launch ();
(* Set the filter to /dev/sda, in case there are any rogue
* PVs lying around on the target disk.
*)
g#lvm_set_filter [|"/dev/sda"|];
(* Update features available in the daemon. *)
ntfs_available := feature_available g [|"ntfsprogs"; "ntfs3g"|];
btrfs_available := feature_available g [|"btrfs"|];
g
let g =
if not quiet then
printf "Examining %s ...\n%!" infile;
let g = connect_both_disks () in
g
(* Get the size in bytes of each disk.
*
* Originally we computed this by looking at the same of the host file,
* but of course this failed for qcow2 images (RHBZ#633096). The right
* way to do it is with g#blockdev_getsize64.
*)
let sectsize, insize, outsize =
let sectsize = g#blockdev_getss "/dev/sdb" in
let insize = g#blockdev_getsize64 "/dev/sda" in
let outsize = g#blockdev_getsize64 "/dev/sdb" in
if debug then (
eprintf "%s size %Ld bytes\n" infile insize;
eprintf "%s size %Ld bytes\n" outfile outsize
);
sectsize, insize, outsize
let max_bootloader =
(* In reality the number of sectors containing boot loader data will be
* less than this (although Windows 7 defaults to putting the first
* partition on sector 2048, and has quite a large boot loader).
*
* However make this large enough to be sure that we have copied over
* the boot loader. We could also do this by looking for the sector
* offset of the first partition.
*
* It doesn't matter if we copy too much.
*)
4096 * 512
(* Check the disks are at least as big as the bootloader. *)
let () =
if insize < Int64.of_int max_bootloader then
error "%s: file is too small to be a disk image (%Ld bytes)"
infile insize;
if outsize < Int64.of_int max_bootloader then
error "%s: file is too small to be a disk image (%Ld bytes)"
outfile outsize
(* Get the source partition type. *)
type parttype = MBR | GPT (* Only these are supported by virt-resize. *)
let parttype, parttype_string =
let pt = g#part_get_parttype "/dev/sda" in
if debug then eprintf "partition table type: %s\n%!" pt;
match pt with
| "msdos" -> MBR, "msdos"
| "gpt" -> GPT, "gpt"
| _ ->
error "%s: unknown partition table type\nvirt-resize only supports MBR (DOS) and GPT partition tables." infile
(* Build a data structure describing the source disk's partition layout.
*
* NOTE: For MBR, only primary/extended partitions are tracked here.
* Logical partitions are contained within an extended partition, and
* we don't track them (they are just copied within the extended
* partition). For the same reason we cannot resize logical partitions.
*)
type partition = {
p_name : string; (* Device name, like /dev/sda1. *)
p_part : G.partition; (* SOURCE partition data from libguestfs. *)
p_bootable : bool; (* Is it bootable? *)
p_mbr_id : int option; (* MBR ID, if it has one. *)
p_type : partition_content; (* Content type and content size. *)
(* What we're going to do: *)
mutable p_operation : partition_operation;
p_target_partnum : int; (* TARGET partition number. *)
p_target_start : int64; (* TARGET partition start (sector num). *)
p_target_end : int64; (* TARGET partition end (sector num). *)
}
and partition_content =
| ContentUnknown (* undetermined *)
| ContentPV of int64 (* physical volume (size of PV) *)
| ContentFS of string * int64 (* mountable filesystem (FS type, FS size) *)
| ContentExtendedPartition (* MBR extended partition *)
and partition_operation =
| OpCopy (* copy it as-is, no resizing *)
| OpIgnore (* ignore it (create on target, but don't
copy any content) *)
| OpDelete (* delete it *)
| OpResize of int64 (* resize it to the new size *)
let rec debug_partition p =
eprintf "%s:\n" p.p_name;
eprintf "\tpartition data: %ld %Ld-%Ld (%Ld bytes)\n"
p.p_part.G.part_num p.p_part.G.part_start p.p_part.G.part_end
p.p_part.G.part_size;
eprintf "\tbootable: %b\n" p.p_bootable;
eprintf "\tpartition ID: %s\n"
(match p.p_mbr_id with None -> "(none)" | Some i -> sprintf "0x%x" i);
eprintf "\tcontent: %s\n" (string_of_partition_content p.p_type)
and string_of_partition_content = function
| ContentUnknown -> "unknown data"
| ContentPV sz -> sprintf "LVM PV (%Ld bytes)" sz
| ContentFS (fs, sz) -> sprintf "filesystem %s (%Ld bytes)" fs sz
| ContentExtendedPartition -> "extended partition"
and string_of_partition_content_no_size = function
| ContentUnknown -> "unknown data"
| ContentPV _ -> sprintf "LVM PV"
| ContentFS (fs, _) -> sprintf "filesystem %s" fs
| ContentExtendedPartition -> "extended partition"
let get_partition_content =
let pvs_full = Array.to_list (g#pvs_full ()) in
fun dev ->
try
let fs = g#vfs_type dev in
if fs = "unknown" then
ContentUnknown
else if fs = "LVM2_member" then (
let rec loop = function
| [] ->
error "%s: physical volume not returned by pvs_full"
dev
| pv :: _ when canonicalize pv.G.pv_name = dev ->
ContentPV pv.G.pv_size
| _ :: pvs -> loop pvs
in
loop pvs_full
)
else (
g#mount_ro dev "/";
let stat = g#statvfs "/" in
let size = stat.G.bsize *^ stat.G.blocks in
ContentFS (fs, size)
)
with
G.Error _ -> ContentUnknown
let is_extended_partition = function
| Some (0x05|0x0f) -> true
| _ -> false
let partitions : partition list =
let parts = Array.to_list (g#part_list "/dev/sda") in
if List.length parts = 0 then
error "the source disk has no partitions";
(* Filter out logical partitions. See note above. *)
let parts =
match parttype with
| GPT -> parts
| MBR ->
List.filter (function
| { G.part_num = part_num } when part_num >= 5_l -> false
| _ -> true
) parts in
let partitions =
List.map (
fun ({ G.part_num = part_num } as part) ->
let part_num = Int32.to_int part_num in
let name = sprintf "/dev/sda%d" part_num in
let bootable = g#part_get_bootable "/dev/sda" part_num in
let mbr_id =
try Some (g#part_get_mbr_id "/dev/sda" part_num)
with G.Error _ -> None in
let typ =
if is_extended_partition mbr_id then ContentExtendedPartition
else get_partition_content name in
{ p_name = name; p_part = part;
p_bootable = bootable; p_mbr_id = mbr_id; p_type = typ;
p_operation = OpCopy; p_target_partnum = 0;
p_target_start = 0L; p_target_end = 0L }
) parts in
if debug then (
eprintf "%d partitions found\n" (List.length partitions);
List.iter debug_partition partitions
);
(* Check content isn't larger than partitions. If it is then
* something has gone wrong and we shouldn't continue. Old
* virt-resize didn't do these checks.
*)
List.iter (
function
| { p_name = name; p_part = { G.part_size = size };
p_type = ContentPV pv_size }
when size < pv_size ->
error "%s: partition size %Ld < physical volume size %Ld"
name size pv_size
| { p_name = name; p_part = { G.part_size = size };
p_type = ContentFS (_, fs_size) }
when size < fs_size ->
error "%s: partition size %Ld < filesystem size %Ld"
name size fs_size
| _ -> ()
) partitions;
(* Check partitions don't overlap. *)
let rec loop end_of_prev = function
| [] -> ()
| { p_name = name; p_part = { G.part_start = part_start } } :: _
when end_of_prev > part_start ->
error "%s: this partition overlaps the previous one" name
| { p_part = { G.part_end = part_end } } :: parts -> loop part_end parts
in
loop 0L partitions;
partitions
(* Build a data structure describing LVs on the source disk.
* This is only used if the user gave the --lv-expand option.
*)
type logvol = {
lv_name : string;
lv_type : logvol_content;
mutable lv_operation : logvol_operation
}
(* ContentPV, ContentExtendedPartition cannot occur here *)
and logvol_content = partition_content
and logvol_operation =
| LVOpNone (* nothing *)
| LVOpExpand (* expand it *)
let debug_logvol lv =
eprintf "%s:\n" lv.lv_name;
eprintf "\tcontent: %s\n" (string_of_partition_content lv.lv_type)
let lvs =
let lvs = Array.to_list (g#lvs ()) in
let lvs = List.map (
fun name ->
let typ = get_partition_content name in
assert (
match typ with ContentPV _ | ContentExtendedPartition -> false
| _ -> true
);
{ lv_name = name; lv_type = typ; lv_operation = LVOpNone }
) lvs in
if debug then (
eprintf "%d logical volumes found\n" (List.length lvs);
List.iter debug_logvol lvs
);
lvs
(* These functions tell us if we know how to expand the content of
* a particular partition or LV, and what method to use.
*)
type expand_content_method =
| PVResize | Resize2fs | NTFSResize | BtrfsFilesystemResize
let string_of_expand_content_method = function
| PVResize -> "pvresize"
| Resize2fs -> "resize2fs"
| NTFSResize -> "ntfsresize"
| BtrfsFilesystemResize -> "btrfs-filesystem-resize"
let can_expand_content =
if expand_content then
function
| ContentUnknown -> false
| ContentPV _ -> true
| ContentFS (("ext2"|"ext3"|"ext4"), _) -> true
| ContentFS (("ntfs"), _) when !ntfs_available -> true
| ContentFS (("btrfs"), _) when !btrfs_available -> true
| ContentFS (_, _) -> false
| ContentExtendedPartition -> false
else
fun _ -> false
let expand_content_method =
if expand_content then
function
| ContentUnknown -> assert false
| ContentPV _ -> PVResize
| ContentFS (("ext2"|"ext3"|"ext4"), _) -> Resize2fs
| ContentFS (("ntfs"), _) when !ntfs_available -> NTFSResize
| ContentFS (("btrfs"), _) when !btrfs_available -> BtrfsFilesystemResize
| ContentFS (_, _) -> assert false
| ContentExtendedPartition -> assert false
else
fun _ -> assert false
(* Helper function to locate a partition given what the user might
* type on the command line. It also gives errors for partitions
* that the user has asked to be ignored or deleted.
*)
let find_partition =
let hash = Hashtbl.create 13 in
List.iter (fun ({ p_name = name } as p) -> Hashtbl.add hash name p)
partitions;
fun ~option name ->
let name =
if String.length name < 5 || String.sub name 0 5 <> "/dev/" then
"/dev/" ^ name
else
name in
let name = canonicalize name in
let partition =
try Hashtbl.find hash name
with Not_found ->
error "%s: partition not found in the source disk image (this error came from '%s' option on the command line). Try running this command: virt-filesystems --partitions --long -a %s"
name option infile in
if partition.p_operation = OpIgnore then
error "%s: partition already ignored, you cannot use it in '%s' option"
name option;
if partition.p_operation = OpDelete then
error "%s: partition already deleted, you cannot use it in '%s' option"
name option;
partition
(* Handle --ignore option. *)
let () =
List.iter (
fun dev ->
let p = find_partition ~option:"--ignore" dev in
p.p_operation <- OpIgnore
) ignores
(* Handle --delete option. *)
let () =
List.iter (
fun dev ->
let p = find_partition ~option:"--delete" dev in
p.p_operation <- OpDelete
) deletes
(* Helper function to mark a partition for resizing. It prevents the
* user from trying to mark the same partition twice. If the force
* flag is given, then we will allow the user to shrink the partition
* even if we think that would destroy the content.
*)
let mark_partition_for_resize ~option ?(force = false) p newsize =
let name = p.p_name in
let oldsize = p.p_part.G.part_size in
(match p.p_operation with
| OpResize _ ->
error "%s: this partition has already been marked for resizing"
name
| OpIgnore | OpDelete ->
(* This error should have been caught already by find_partition ... *)
error "%s: this partition has already been ignored or deleted"
name
| OpCopy -> ()
);
(* Only do something if the size will change. *)
if oldsize <> newsize then (
let bigger = newsize > oldsize in
if not bigger && not force then (
(* Check if this contains filesystem content, and how big that is
* and whether we will destroy any content by shrinking this.
*)
match p.p_type with
| ContentUnknown ->
error "%s: This partition has unknown content which might be damaged by shrinking it. If you want to shrink this partition, you need to use the '--resize-force' option, but that could destroy any data on this partition. (This error came from '%s' option on the command line.)"
name option
| ContentPV size when size > newsize ->
error "%s: This partition has contains an LVM physical volume which will be damaged by shrinking it below %Ld bytes (user asked to shrink it to %Ld bytes). If you want to shrink this partition, you need to use the '--resize-force' option, but that could destroy any data on this partition. (This error came from '%s' option on the command line.)"
name size newsize option
| ContentPV _ -> ()
| ContentFS (fstype, size) when size > newsize ->
error "%s: This partition has contains a %s filesystem which will be damaged by shrinking it below %Ld bytes (user asked to shrink it to %Ld bytes). If you want to shrink this partition, you need to use the '--resize-force' option, but that could destroy any data on this partition. (This error came from '%s' option on the command line.)"
name fstype size newsize option
| ContentFS _ -> ()
| ContentExtendedPartition ->
error "%s: This extended partition contains logical partitions which might be damaged by shrinking it. If you want to shrink this partition, you need to use the '--resize-force' option, but that could destroy logical partitions within this partition. (This error came from '%s' option on the command line.)"
name option
);
p.p_operation <- OpResize newsize
)
(* Handle --resize and --resize-force options. *)
let () =
let do_resize ~option ?(force = false) arg =
(* Argument is "dev=size". *)
let dev, sizefield =
try
let i = String.index arg '=' in
let n = String.length arg - (i+1) in
if n == 0 then raise Not_found;
String.sub arg 0 i, String.sub arg (i+1) n
with Not_found ->
error "%s: missing size field in '%s' option" arg option in
let p = find_partition ~option dev in
(* Parse the size field. *)
let oldsize = p.p_part.G.part_size in
let newsize = parse_size oldsize sizefield in
if newsize <= 0L then
error "%s: new partition size is zero or negative" dev;
mark_partition_for_resize ~option ~force p newsize
in
List.iter (do_resize ~option:"--resize") resizes;
List.iter (do_resize ~option:"--resize-force" ~force:true) resizes_force
(* Helper function calculates the surplus space, given the total
* required so far for the current partition layout, compared to
* the size of the target disk. If the return value >= 0 then it's
* a surplus, if it is < 0 then it's a deficit.
*)
let calculate_surplus () =
(* We need some overhead for partitioning. Worst case would be for
* EFI partitioning + massive per-partition alignment.
*)
let nr_partitions = List.length partitions in
let overhead = (Int64.of_int sectsize) *^ (
2L *^ 64L +^ (* GPT start and end *)
(alignment *^ (Int64.of_int (nr_partitions + 1))) (* Maximum alignment *)
) +^
(Int64.of_int (max_bootloader - 64 * 512)) in (* Bootloader *)
let required = List.fold_left (
fun total p ->
let newsize =
match p.p_operation with
| OpCopy | OpIgnore -> p.p_part.G.part_size
| OpDelete -> 0L
| OpResize newsize -> newsize in
total +^ newsize
) 0L partitions in
outsize -^ (required +^ overhead)
(* Handle --expand and --shrink options. *)
let () =
if expand <> None && shrink <> None then
error "you cannot use options --expand and --shrink together";
if expand <> None || shrink <> None then (
let surplus = calculate_surplus () in
if debug then
eprintf "surplus before --expand or --shrink: %Ld\n" surplus;
(match expand with
| None -> ()
| Some dev ->
if surplus < 0L then
error "You cannot use --expand when there is no surplus space to expand into. You need to make the target disk larger by at least %s."
(human_size (Int64.neg surplus));
let option = "--expand" in
let p = find_partition ~option dev in
let oldsize = p.p_part.G.part_size in
mark_partition_for_resize ~option p (oldsize +^ surplus)
);
(match shrink with
| None -> ()
| Some dev ->
if surplus > 0L then
error "You cannot use --shrink when there is no deficit (see 'deficit' in the virt-resize(1) man page).";
let option = "--shrink" in
let p = find_partition ~option dev in
let oldsize = p.p_part.G.part_size in
mark_partition_for_resize ~option p (oldsize +^ surplus)
)
)
(* Calculate the final surplus.
* At this point, this number must be >= 0.
*)
let surplus =
let surplus = calculate_surplus () in
if surplus < 0L then (
let deficit = Int64.neg surplus in
error "There is a deficit of %Ld bytes (%s). You need to make the target disk larger by at least this amount or adjust your resizing requests."
deficit (human_size deficit)
);
surplus
(* Mark the --lv-expand LVs. *)
let () =
let hash = Hashtbl.create 13 in
List.iter (fun ({ lv_name = name } as lv) -> Hashtbl.add hash name lv) lvs;
List.iter (
fun name ->
let lv =
try Hashtbl.find hash name
with Not_found ->
error "%s: logical volume not found in the source disk image (this error came from '--lv-expand' option on the command line). Try running this command: virt-filesystems --logical-volumes --long -a %s"
name infile in
lv.lv_operation <- LVOpExpand
) lv_expands
(* Print a summary of what we will do. *)
let () =
flush stderr;
if not quiet then (
printf "**********\n\n";
printf "Summary of changes:\n\n";
List.iter (
fun ({ p_name = name; p_part = { G.part_size = oldsize }} as p) ->
let text =
match p.p_operation with
| OpCopy ->
sprintf "%s: This partition will be left alone." name
| OpIgnore ->
sprintf "%s: This partition will be created, but the contents will be ignored (ie. not copied to the target)." name
| OpDelete ->
sprintf "%s: This partition will be deleted." name
| OpResize newsize ->
sprintf "%s: This partition will be resized from %s to %s."
name (human_size oldsize) (human_size newsize) ^
if can_expand_content p.p_type then (
sprintf " The %s on %s will be expanded using the '%s' method."
(string_of_partition_content_no_size p.p_type)
name
(string_of_expand_content_method
(expand_content_method p.p_type))
) else "" in
wrap ~hanging:4 (text ^ "\n\n")
) partitions;
List.iter (
fun ({ lv_name = name } as lv) ->
match lv.lv_operation with
| LVOpNone -> ()
| LVOpExpand ->
let text =
sprintf "%s: This logical volume will be expanded to maximum size."
name ^
if can_expand_content lv.lv_type then (
sprintf " The %s on %s will be expanded using the '%s' method."
(string_of_partition_content_no_size lv.lv_type)
name
(string_of_expand_content_method
(expand_content_method lv.lv_type))
) else "" in
wrap ~hanging:4 (text ^ "\n\n")
) lvs;
if surplus > 0L then (
let text =
sprintf "There is a surplus of %s." (human_size surplus) ^
if extra_partition then (
if surplus >= min_extra_partition then
sprintf " An extra partition will be created for the surplus."
else
sprintf " The surplus space is not large enough for an extra partition to be created and so it will just be ignored."
) else
sprintf " The surplus space will be ignored. Run a partitioning program in the guest to partition this extra space if you want." in
wrap (text ^ "\n\n")
);
printf "**********\n";
flush stdout
);
if dryrun then exit 0
(* Create a partition table.
*
* We *must* do this before copying the bootloader across, and copying
* the bootloader must be careful not to disturb this partition table
* (RHBZ#633766). There are two reasons for this:
*
* (1) The 'parted' library is stupid and broken. In many ways. In
* this particular instance the stupid and broken bit is that it
* overwrites the whole boot sector when initializating a partition
* table. (Upstream don't consider this obvious problem to be a bug).
*
* (2) GPT has a backup partition table located at the end of the disk.
* It's non-movable, because the primary GPT contains fixed references
* to both the size of the disk and the backup partition table at the
* end. This would be a problem for any resize that didn't either
* carefully move the backup GPT (and rewrite those references) or
* recreate the whole partition table from scratch.
*)
let g =
(* Try hard to initialize the partition table. This might involve
* relaunching another handle.
*)
if not quiet then
printf "Setting up initial partition table on %s ...\n%!" outfile;
let last_error = ref "" in
let rec initialize_partition_table g attempts =
let ok =
try g#part_init "/dev/sdb" parttype_string; true
with G.Error error -> last_error := error; false in
if ok then g, true
else if attempts > 0 then (
g#zero "/dev/sdb";
g#sync ();
g#close ();
let g = connect_both_disks () in
initialize_partition_table g (attempts-1)
)
else g, false
in
let g, ok = initialize_partition_table g 5 in
if not ok then
error "Failed to initialize the partition table on the target disk. You need to wipe or recreate the target disk and then run virt-resize again.\n\nThe underlying error was: %s" !last_error;
g
(* Copy the bootloader across.
* Don't disturb the partition table that we just wrote.
* https://secure.wikimedia.org/wikipedia/en/wiki/Master_Boot_Record
* https://secure.wikimedia.org/wikipedia/en/wiki/GUID_Partition_Table
*)
let () =
if copy_boot_loader then (
let bootsect = g#pread_device "/dev/sda" 446 0L in
if String.length bootsect < 446 then
error "pread-device: short read";
ignore (g#pwrite_device "/dev/sdb" bootsect 0L);
let start =
if parttype <> GPT then 512L
else
(* XXX With 4K sectors does GPT just fit more entries in a
* sector, or does it always use 34 sectors?
*)
17408L in
let loader = g#pread_device "/dev/sda" max_bootloader start in
if String.length loader < max_bootloader then
error "pread-device: short read";
ignore (g#pwrite_device "/dev/sdb" loader start)
)
(* Are we going to align the first partition and fix the bootloader? *)
let align_first_partition_and_fix_bootloader =
(* Bootloaders that we know how to fix:
* - first partition is NTFS, and
* - first partition is bootable, and
* - only one partition (ie. not Win Vista and later), and
* - it's not already aligned to some small value (no point
* moving it around unnecessarily)
*)
let rec can_fix_boot_loader () =
match partitions with
| [ { p_part = { G.part_start = start };
p_type = ContentFS ("ntfs", _);
p_bootable = true;
p_operation = OpCopy | OpIgnore | OpResize _ } ]
when not_aligned_enough start -> true
| _ -> false
and not_aligned_enough start =
let alignment = alignment_of start in
alignment < 12 (* < 4K alignment *)
and alignment_of = function
| 0L -> 64
| n when n &^ 1L = 1L -> 0
| n -> 1 + alignment_of (n /^ 2L)
in
match align_first, can_fix_boot_loader () with
| `Never, _
| `Auto, false -> false
| `Always, _
| `Auto, true -> true
let () =
if debug then
eprintf "align_first_partition_and_fix_bootloader = %b\n%!"
align_first_partition_and_fix_bootloader
(* Repartition the target disk. *)
(* Calculate the location of the partitions on the target disk. This
* also removes from the list any partitions that will be deleted, so
* the final list just contains partitions that need to be created
* on the target.
*)
let partitions =
let sectsize = Int64.of_int sectsize in
(* Return 'i' rounded up to the next multiple of 'a'. *)
let roundup64 i a = let a = a -^ 1L in (i +^ a) &^ (~^ a) in
let rec loop partnum start = function
| p :: ps ->
(match p.p_operation with
| OpDelete -> loop partnum start ps (* skip p *)
| OpIgnore | OpCopy -> (* same size *)
(* Size in sectors. *)
let size = (p.p_part.G.part_size +^ sectsize -^ 1L) /^ sectsize in
(* Start of next partition + alignment. *)
let end_ = start +^ size in
let next = roundup64 end_ alignment in
{ p with p_target_start = start; p_target_end = end_ -^ 1L;
p_target_partnum = partnum } :: loop (partnum+1) next ps
| OpResize newsize -> (* resized partition *)
(* New size in sectors. *)
let size = (newsize +^ sectsize -^ 1L) /^ sectsize in
(* Start of next partition + alignment. *)
let next = start +^ size in
let next = roundup64 next alignment in
{ p with p_target_start = start; p_target_end = next -^ 1L;
p_target_partnum = partnum } :: loop (partnum+1) next ps
)
| [] ->
(* Create the surplus partition if there is room for it. *)
if extra_partition && surplus >= min_extra_partition then (
[ {
(* Since this partition has no source, this data is
* meaningless and not used since the operation is
* OpIgnore.
*)
p_name = "";
p_part = { G.part_num = 0l; part_start = 0L; part_end = 0L;
part_size = 0L };
p_bootable = false; p_mbr_id = None; p_type = ContentUnknown;
(* Target information is meaningful. *)
p_operation = OpIgnore;
p_target_partnum = partnum;
p_target_start = start; p_target_end = ~^ 64L
} ]
)
else
[]
in
(* Choose the alignment of the first partition based on the
* '--align-first' option. Old virt-resize used to always align this
* to 64 sectors, but this causes boot failures unless we are able to
* adjust the bootloader accordingly.
*)
let start =
if align_first_partition_and_fix_bootloader then
alignment
else
(* Preserve the existing start, but convert to sectors. *)
(List.hd partitions).p_part.G.part_start /^ sectsize in
loop 1 start partitions
(* Now partition the target disk. *)
let () =
List.iter (
fun p ->
g#part_add "/dev/sdb" "primary" p.p_target_start p.p_target_end
) partitions
(* Copy over the data. *)
let () =
List.iter (
fun p ->
match p.p_operation with
| OpCopy | OpResize _ ->
(* XXX Old code had 'when target_partnum > 0', but it appears
* to have served no purpose since the field could never be 0
* at this point.
*)
let oldsize = p.p_part.G.part_size in
let newsize =
match p.p_operation with OpResize s -> s | _ -> oldsize in
let copysize = if newsize < oldsize then newsize else oldsize in
let source = p.p_name in
let target = sprintf "/dev/sdb%d" p.p_target_partnum in
if not quiet then
printf "Copying %s ...\n%!" source;
(match p.p_type with
| ContentUnknown | ContentPV _ | ContentFS _ ->
g#copy_device_to_device ~size:copysize source target
| ContentExtendedPartition ->
(* You can't just copy an extended partition by name, eg.
* source = "/dev/sda2", because the device name only covers
* the first 1K of the partition. Instead, copy the
* source bytes from the parent disk (/dev/sda).
*)
let srcoffset = p.p_part.G.part_start in
g#copy_device_to_device ~srcoffset ~size:copysize "/dev/sda" target
)
| _ -> ()
) partitions
(* Set bootable and MBR IDs. Do this *after* copying over the data,
* so that we can magically change the primary partition to an extended
* partition if necessary.
*)
let () =
List.iter (
fun p ->
if p.p_bootable then
g#part_set_bootable "/dev/sdb" p.p_target_partnum true;
(match p.p_mbr_id with
| None -> ()
| Some mbr_id ->
g#part_set_mbr_id "/dev/sdb" p.p_target_partnum mbr_id
);
) partitions
(* Fix the bootloader if we aligned the first partition. *)
let () =
if align_first_partition_and_fix_bootloader then (
(* See can_fix_boot_loader above. *)
match partitions with
| { p_type = ContentFS ("ntfs", _); p_bootable = true;
p_target_partnum = partnum; p_target_start = start } :: _ ->
(* If the first partition is NTFS and bootable, set the "Number of
* Hidden Sectors" field in the NTFS Boot Record so that the
* filesystem is still bootable.
*)
(* Should always be /dev/sdb1? *)
let target = sprintf "/dev/sdb%d" partnum in
(* Sanity check: it contains the NTFS magic. *)
let magic = g#pread_device target 8 3L in
if magic <> "NTFS " then
eprintf "warning: first partition is NTFS but does not contain NTFS boot loader magic\n%!"
else (
if not quiet then
printf "Fixing first NTFS partition boot record ...\n%!";
if debug then (
let old_hidden = int_of_le32 (g#pread_device target 4 0x1c_L) in
eprintf "old hidden sectors value: 0x%Lx\n%!" old_hidden
);
let new_hidden = le32_of_int start in
ignore (g#pwrite_device target new_hidden 0x1c_L)
)
| _ -> ()
)
(* After copying the data over we must shut down and restart the
* appliance in order to expand the content. The reason for this may
* not be obvious, but it's because otherwise we'll have duplicate VGs
* (the old VG(s) and the new VG(s)) which breaks LVM.
*
* The restart is only required if we're going to expand something.
*)
let to_be_expanded =
List.exists (
function
| ({ p_operation = OpResize _ } as p) -> can_expand_content p.p_type
| _ -> false
) partitions
|| List.exists (
function
| ({ lv_operation = LVOpExpand } as lv) -> can_expand_content lv.lv_type
| _ -> false
) lvs
let g =
if to_be_expanded then (
g#umount_all ();
g#sync ();
g#close ();
let g = new G.guestfs () in
if debug then g#set_trace true;
g#add_drive_opts ?format:output_format ~readonly:false outfile;
if not quiet then Progress.set_up_progress_bar ~machine_readable g;
g#launch ();
g (* Return new handle. *)
)
else g (* Return existing handle. *)
let () =
if to_be_expanded then (
(* Helper function to expand partition or LV content. *)
let do_expand_content target = function
| PVResize -> g#pvresize target
| Resize2fs ->
g#e2fsck_f target;
g#resize2fs target
| NTFSResize -> g#ntfsresize_opts ~force:ntfsresize_force target
| BtrfsFilesystemResize ->
(* Complicated ... Btrfs forces us to mount the filesystem
* in order to resize it.
*)
assert (Array.length (g#mounts ()) = 0);
g#mount_options "" target "/";
g#btrfs_filesystem_resize "/";
g#umount "/"
in
(* Expand partition content as required. *)
List.iter (
function
| ({ p_operation = OpResize _ } as p) when can_expand_content p.p_type ->
let source = p.p_name in
let target = sprintf "/dev/sda%d" p.p_target_partnum in
let meth = expand_content_method p.p_type in
if not quiet then
printf "Expanding %s%s using the '%s' method ...\n%!"
source
(if source <> target then sprintf " (now %s)" target else "")
(string_of_expand_content_method meth);
do_expand_content target meth
| _ -> ()
) partitions;
(* Expand logical volume content as required. *)
List.iter (
function
| ({ lv_operation = LVOpExpand } as lv) when can_expand_content lv.lv_type ->
let name = lv.lv_name in
let meth = expand_content_method lv.lv_type in
if not quiet then
printf "Expanding %s using the '%s' method ...\n%!"
name
(string_of_expand_content_method meth);
(* First expand the LV itself to maximum size. *)
g#lvresize_free name 100;
(* Then expand the content in the LV. *)
do_expand_content name meth
| _ -> ()
) lvs
)
(* Finished. Unmount disks and exit. *)
let () =
g#umount_all ();
g#sync ();
g#close ();
if not quiet then (
print_newline ();
wrap "Resize operation completed with no errors. Before deleting the old disk, carefully check that the resized disk boots and works correctly.\n";
);
if debug_gc then
Gc.compact ();
exit 0