1 (* Diskimage library for reading disk images.
2 (C) Copyright 2007-2008 Richard W.M. Jones, Red Hat Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 (* Use as the natural block size for disk images, but really we should
29 * use the 'blockdev -getbsz' command to find the real block size.
31 let disk_block_size = ~^512
33 class virtual device =
35 method virtual size : int63
36 method virtual name : string
37 method virtual blocksize : int63
38 method virtual map_block : int63 -> (device * int63) list
39 method virtual contiguous : Int63.t -> Int63.t
41 (* Block-based read. Inefficient so normally overridden in subclasses. *)
42 method read offset len =
43 if offset < ~^0 || len < ~^0 then
44 invalid_arg "device: read: negative offset or length";
46 let blocksize = self#blocksize in
48 (* Break the request into blocks.
49 * Find the first and last blocks of this request.
51 let first_blk = offset /^ blocksize in
52 let offset_in_first_blk = offset -^ first_blk *^ blocksize in
53 let last_blk = (offset +^ len -^ ~^1) /^ blocksize in
55 (* Buffer for the result. *)
56 let buf = Buffer.create (Int63.to_int len) in
58 let not_mapped_error () = invalid_arg "device: read: block not mapped" in
60 (* Copy the first block (partial). *)
61 (match self#map_block first_blk with
62 | [] -> not_mapped_error ()
65 min len (blocksize -^ offset_in_first_blk) in
66 let str = dev#read (base +^ offset_in_first_blk) len in
67 Buffer.add_string buf str
70 (* Copy the middle blocks. *)
72 if blk < last_blk then (
73 (match self#map_block blk with
74 | [] -> not_mapped_error ()
76 let str = dev#read ~^0 self#blocksize in
77 Buffer.add_string buf str
82 loop (Int63.succ first_blk);
84 (* Copy the last block (partial). *)
85 if first_blk < last_blk then (
86 match self#map_block last_blk with
87 | [] -> not_mapped_error ()
89 let len = (offset +^ len) -^ last_blk *^ blocksize in
90 let str = dev#read ~^0 len in
91 Buffer.add_string buf str
94 assert (Int63.to_int len = Buffer.length buf);
97 (* Helper method to read a chunk of data into a bitstring. *)
98 method read_bitstring offset len =
99 let str = self#read offset len in
100 (str, 0, String.length str lsl 3)
103 (* A concrete device which just direct-maps a file or /dev device. *)
104 class block_device filename blocksize =
105 let fd = openfile filename [ O_RDONLY ] 0 in
106 let size = Int63.of_int64 (LargeFile.fstat fd).LargeFile.st_size in
109 method read offset len =
110 let offset = Int63.to_int64 offset in
111 let len = Int63.to_int len in
112 ignore (LargeFile.lseek fd offset SEEK_SET);
113 let str = String.make len '\000' in
114 ignore (read fd str 0 len);
117 method name = filename
118 method blocksize = blocksize
119 method map_block _ = []
120 method contiguous offset =
122 method close () = close fd
125 (* A linear offset/size from an underlying device. *)
126 class offset_device name start size blocksize (dev : device) =
131 method read offset len =
132 if offset < ~^0 || len < ~^0 || offset +^ len > size then
134 sprintf "%s: tried to read outside device boundaries (%s/%s/%s)"
135 name (Int63.to_string offset) (Int63.to_string len)
136 (Int63.to_string size)
138 dev#read (start+^offset) len
139 method blocksize = blocksize
140 method map_block i = [dev, i *^ blocksize +^ start]
141 method contiguous offset =
145 (* A device with just a modified block size. *)
146 class blocksize_overlay new_blocksize (dev : device) =
149 method name = dev#name
150 method size = dev#size
151 method read = dev#read
152 method blocksize = new_blocksize
153 method map_block new_blk =
154 let orig_blk = new_blk *^ new_blocksize /^ dev#blocksize in
155 dev#map_block orig_blk
156 method contiguous offset = dev#size -^ offset
159 (* The null device. Any attempt to read generates an error. *)
160 let null_device : device =
163 method read _ _ = assert false
166 method blocksize = ~^1
167 method map_block _ = assert false
168 method contiguous _ = ~^0
172 m_name : string; (* Machine name. *)
173 m_disks : disk list; (* Machine disks. *)
175 (lv * filesystem) list; (* Machine LV filesystems. *)
178 d_name : string; (* Device name (eg "hda") *)
180 (* About the device itself. *)
181 d_dev : block_device; (* Disk device. *)
182 d_content : disk_content; (* What's on it. *)
185 [ `Unknown (* Not probed or unknown. *)
186 | `Partitions of partitions (* Contains partitions. *)
187 | `Filesystem of filesystem (* Contains a filesystem directly. *)
188 | `PhysicalVolume of pv (* Contains an LVM PV. *)
194 parts_cb : partitioner_callbacks; (* Partitioning scheme. *)
195 parts_dev : device; (* Partitions (whole) device. *)
196 parts : partition list (* Partitions. *)
199 part_status : partition_status; (* Bootable, etc. *)
200 part_type : int; (* Partition filesystem type. *)
201 part_dev : device; (* Partition device. *)
202 part_content : partition_content; (* What's on it. *)
204 and partition_status = Bootable | Nonbootable | Malformed | NullEntry
205 and partition_content =
206 [ `Unknown (* Not probed or unknown. *)
207 | `Filesystem of filesystem (* Filesystem. *)
208 | `PhysicalVolume of pv (* Contains an LVM PV. *)
211 (* Filesystems (also swap devices). *)
213 fs_cb : filesystem_callbacks; (* Filesystem. *)
214 fs_dev : device; (* Device containing the filesystem. *)
215 fs_blocksize : int63; (* Block size (bytes). *)
216 fs_blocks_total : int63; (* Total blocks. *)
217 fs_is_swap : bool; (* If swap, following not valid. *)
218 fs_blocks_reserved : int63; (* Blocks reserved for super-user. *)
219 fs_blocks_avail : int63; (* Blocks free (available). *)
220 fs_blocks_used : int63; (* Blocks in use. *)
221 fs_inodes_total : int63; (* Total inodes. *)
222 fs_inodes_reserved : int63; (* Inodes reserved for super-user. *)
223 fs_inodes_avail : int63; (* Inodes free (available). *)
224 fs_inodes_used : int63; (* Inodes in use. *)
227 (* Physical volumes. *)
229 pv_cb : lvm_callbacks; (* The LVM plug-in. *)
230 pv_dev : device; (* Device covering whole PV. *)
231 pv_uuid : string; (* UUID. *)
234 (* Logical volumes. *)
236 lv_dev : device; (* Logical volume device. *)
239 (* Tables of callbacks. *)
240 and partitioner_probe = device -> partitions
242 and partitioner_callbacks = {
243 parts_cb_name : string;
244 parts_cb_offset_is_free : partitions -> Int63.t -> bool;
247 and filesystem_probe = device -> filesystem
249 and filesystem_callbacks = {
251 fs_cb_printable_name : string;
252 fs_cb_offset_is_free : filesystem -> Int63.t -> bool;
255 and lvm_probe = device -> pv
257 and lvm_callbacks = {
258 lvm_cb_name : string;
259 lvm_cb_list_lvs : pv list -> lv list;
260 lvm_cb_offset_is_free : pv -> Int63.t -> bool;
263 let name_of_filesystem { fs_cb = { fs_cb_printable_name = name } } = name
265 (*----------------------------------------------------------------------*)
266 (* Helper functions. *)
268 (* Convert a UUID (containing '-' chars) to canonical form. *)
269 let canonical_uuid uuid =
270 let uuid' = String.make 32 ' ' in
272 for i = 0 to String.length uuid - 1 do
273 if !j >= 32 then invalid_arg "canonical_uuid";
275 if c <> '-' then ( uuid'.[!j] <- c; incr j )
277 if !j <> 32 then invalid_arg "canonical_uuid";
280 (* This version by Isaac Trotts. *)
281 let group_by ?(cmp = Pervasives.compare) ls =
284 (fun acc (day1, x1) ->
287 | (day2, ls2) :: acctl ->
289 then (day1, x1 :: ls2) :: acctl
290 else (day1, [x1]) :: acc)
294 let ls' = List.rev ls' in
295 List.map (fun (x, xs) -> x, List.rev xs) ls'
297 let rec uniq ?(cmp = Pervasives.compare) = function
300 | x :: y :: xs when cmp x y = 0 ->
305 let sort_uniq ?cmp xs =
306 let xs = ExtList.List.sort ?cmp xs in
307 let xs = uniq ?cmp xs in
311 if a < b then a :: range (a+1) b
314 (*----------------------------------------------------------------------*)
317 let partitioners = ref []
318 let filesystems = ref []
321 let register_plugin ?partitioner ?filesystem ?lvm id =
322 (match partitioner with
324 | Some probe -> partitioners := !partitioners @ [id, probe]
326 (match filesystem with
328 | Some probe -> filesystems := !filesystems @ [id, probe]
332 | Some probe -> lvms := !lvms @ [id, probe]
335 (* Probe a device for partitions. Returns [Some parts] or [None]. *)
336 let probe_for_partitions dev =
337 if !debug then eprintf "probing for partitions on %s ...\n%!" dev#name;
338 let rec loop = function
340 | (_, probe) :: rest ->
342 with Not_found -> loop rest
344 let r = loop !partitioners in
347 | None -> eprintf "no partitions found on %s\n%!" dev#name
348 | Some { parts_cb = { parts_cb_name = name }; parts = parts } ->
349 eprintf "found %d %s partitions on %s\n"
350 (List.length parts) name dev#name
354 (* Probe a device for a filesystem. Returns [Some fs] or [None]. *)
355 let probe_for_filesystem dev =
356 if !debug then eprintf "probing for a filesystem on %s ...\n%!" dev#name;
357 let rec loop = function
359 | (_, probe) :: rest ->
361 with Not_found -> loop rest
363 let r = loop !filesystems in
366 | None -> eprintf "no filesystem found on %s\n%!" dev#name
368 eprintf "found a filesystem on %s:\n" dev#name;
369 eprintf "\t%s\n%!" fs.fs_cb.fs_cb_name
373 (* Probe a device for a PV. Returns [Some pv] or [None]. *)
374 let probe_for_pv dev =
375 if !debug then eprintf "probing if %s is a PV ...\n%!" dev#name;
376 let rec loop = function
378 | (_, probe) :: rest ->
380 with Not_found -> loop rest
382 let r = loop !lvms in
385 | None -> eprintf "no PV found on %s\n%!" dev#name
386 | Some { pv_cb = { lvm_cb_name = name } } ->
387 eprintf "%s contains a %s PV\n%!" dev#name name
391 (*----------------------------------------------------------------------*)
392 (* Create machine description. *)
393 let open_machine name disks =
394 let disks = List.map (
396 let dev = new block_device path disk_block_size (* XXX *) in
397 { d_name = name; d_dev = dev; d_content = `Unknown }
399 { m_name = name; m_disks = disks; m_lv_filesystems = [] }
401 let close_machine { m_disks = m_disks } =
402 (* Only close the disks, assume all other devices are derived from them. *)
403 List.iter (fun { d_dev = d_dev } -> d_dev#close ()) m_disks
405 (* Main scanning function for filesystems. *)
406 let scan_machine ({ m_disks = m_disks } as machine) =
407 let m_disks = List.map (
408 fun ({ d_dev = dev } as disk) ->
409 let dev = (dev :> device) in
410 (* See if it is partitioned first. *)
411 let parts = probe_for_partitions dev in
414 { disk with d_content = `Partitions parts }
416 (* Not partitioned. Does it contain a filesystem? *)
417 let fs = probe_for_filesystem dev in
420 { disk with d_content = `Filesystem fs }
422 (* Not partitioned, no filesystem, is it a PV? *)
423 let pv = probe_for_pv dev in
426 { disk with d_content = `PhysicalVolume pv }
428 disk (* Spare/unknown. *)
431 (* Now we have either detected partitions or a filesystem on each
432 * physical device (or perhaps neither). See what is on those
435 let m_disks = List.map (
437 | ({ d_dev = dev; d_content = `Partitions parts } as disk) ->
440 if p.part_status = Bootable || p.part_status = Nonbootable then (
441 let fs = probe_for_filesystem p.part_dev in
444 { p with part_content = `Filesystem fs }
447 let pv = probe_for_pv p.part_dev in
450 { p with part_content = `PhysicalVolume lvm_name }
452 p (* Spare/unknown. *)
455 let parts = { parts with parts = ps } in
456 { disk with d_content = `Partitions parts }
460 (* LVM filesystem detection
462 * Look for all disks/partitions which have been identified as PVs
463 * and pass those back to the respective LVM plugin for LV detection.
465 * (Note - a two-stage process because an LV can be spread over
466 * several PVs, so we have to detect all PVs belonging to a
469 * XXX To deal with RAID (ie. md devices) we will need to loop
470 * around here because RAID is like LVM except that they normally
471 * present as block devices which can be used by LVM.
473 (* First: LV detection.
474 * Find all physical volumes, can be disks or partitions.
476 let pvs_on_disks = List.filter_map (
478 | { d_content = `PhysicalVolume pv } -> Some pv
481 let pvs_on_partitions = List.map (
483 | { d_content = `Partitions { parts = parts } } ->
486 | { part_content = `PhysicalVolume pv } -> Some pv
491 let lvs = List.concat (pvs_on_disks :: pvs_on_partitions) in
493 (* Second: filesystem on LV detection.
494 * Group the LVs by LVM plug-in ID.
497 List.map (fun ({pv_cb = {lvm_cb_name = name}} as pv) -> name, pv) lvs in
498 let lvs = List.sort lvs in
499 let lvs = group_by lvs in
501 let lvs = List.map (fun (name, pvs) ->
502 let pv = List.hd pvs in
503 pv.pv_cb.lvm_cb_list_lvs pvs) lvs in
504 let lvs = List.concat lvs in
506 (* lvs is a list of potential LV devices. Now run them through the
507 * probes to see if any contain filesystems.
511 fun ({ lv_dev = dev } as lv) ->
512 match probe_for_filesystem dev with
513 | Some fs -> Some (lv, fs)
519 m_lv_filesystems = filesystems }
521 (*----------------------------------------------------------------------*)
523 (* We describe the ownership of each part of the disk using a
524 * segment tree. http://en.wikipedia.org/wiki/Segment_tree
526 * Note that each part can (and usually is) owned multiple times
527 * (eg. by a filesystem and by the partition that the filesystem
528 * lies inside). Also, the segment tree is effectively read-only.
529 * We build it up as a final step given the flat list of segments
530 * identified by the algorithm in 'iter_over_machine'.
533 (* General binary tree type. Data 'a is stored in the leaves and 'b
534 * is stored in the nodes.
536 type ('a,'b) binary_tree =
538 | Node of ('a,'b) binary_tree * 'b * ('a,'b) binary_tree
540 (* This prints out the binary tree in graphviz dot format. *)
541 let print_binary_tree leaf_printer node_printer tree =
542 (* Assign a unique, fixed label to each node. *)
545 let hash = Hashtbl.create 13 in
547 try Hashtbl.find hash node
549 let i = incr i; !i in
550 let label = "n" ^ string_of_int i in
551 Hashtbl.add hash node label;
554 (* Recursively generate the graphviz file. *)
555 let rec print = function
556 | (Leaf a as leaf) ->
557 eprintf " %s [shape=box, label=\"%s\"];\n"
558 (label leaf) (leaf_printer a)
559 | (Node (left,b,right) as node) ->
560 eprintf " %s [label=\"%s\"];\n"
561 (label node) (node_printer b);
562 eprintf " %s -> %s [tailport=sw];\n" (label node) (label left);
563 eprintf " %s -> %s [tailport=se];\n" (label node) (label right);
567 eprintf "/* Use 'dot -Tpng foo.dot > foo.png' to convert to a png file. */\n";
568 eprintf "digraph G {\n";
573 [ `Filesystem of filesystem
574 | `Partitions of partitions
575 | `PhysicalVolume of pv ]
577 (* A segment describes the owner of a range of disk addresses. *)
578 type segment = owner * int63 (* owner, owner offset *)
580 type interval = int63 * int63 (* start point, end point (bytes) *)
582 (* The special segment tree structure that we construct in create_ownership. *)
584 (interval * segment list, interval * segment list) binary_tree
587 (device * (* block_device (disk) *)
588 segment_tree) list (* segment tree for this disk *)
590 (* List of owned segments before we build the segment tree. *)
591 type ownership_list =
592 (device * (* block_device (disk) *)
593 (int63 * int63 * (* disk offset, size of segment *)
594 owner * int63 (* owner, owner offset *)
598 (* Ownership tables. *)
599 let create_ownership machine =
600 (* Iterate over all the things which can claim ownership of a
601 * disk block (filesystems, partitions, PVs).
603 let rec iter_over_machine
604 ({m_disks = disks; m_lv_filesystems = lv_filesystems} as machine) =
606 (* No segments to begin with. *)
607 let ownership = [] in
609 (* Iterate over disks. *)
614 | { d_content = (`Filesystem fs as owner) } ->
615 iter_over_filesystem machine ownership fs owner
616 | { d_content = (`Partitions parts as owner) } ->
617 iter_over_partitions machine ownership parts owner
618 | { d_content = (`PhysicalVolume pv as owner) } ->
619 iter_over_pv machine ownership pv owner
620 | { d_content = `Unknown } -> ownership
623 (* Iterate over LV filesystems. *)
626 fun ownership (lv, fs) ->
627 let owner = `Filesystem fs in
628 iter_over_filesystem machine ownership fs owner
629 ) ownership lv_filesystems in
633 (* Iterate over the blocks in a single filesystem. *)
634 and iter_over_filesystem machine ownership {fs_dev = dev} owner =
635 iter_over_device machine ownership dev owner
637 (* Iterate over the blocks in a set of partitions, then
638 * iterate over the contents of the partitions.
640 and iter_over_partitions machine ownership
641 {parts = parts; parts_dev = parts_dev} owner =
642 let ownership = iter_over_device machine ownership parts_dev owner in
648 | { part_content = (`Filesystem fs as owner) } ->
649 iter_over_filesystem machine ownership fs owner
650 | { part_content = (`PhysicalVolume pv as owner) } ->
651 iter_over_pv machine ownership pv owner
652 | { part_content = `Unknown } -> ownership
657 (* Iterate over the blocks in a PV. *)
658 and iter_over_pv machine ownership {pv_dev = dev} owner =
659 iter_over_device machine ownership dev owner
661 (* Iterate over the blocks in a device, assigning ownership to 'owner'
663 * In reality (1): There can be several owners for each block, so we
664 * incrementally add ownership to the ownership_list (which eventually
665 * will be turned into a segment tree).
666 * In reality (2): Iterating over blocks would take ages and result
667 * in a very inefficient ownership representation. Instead we look
668 * at minimum contiguous extents.
670 and iter_over_device { m_disks = disks } ownership dev owner =
671 let size = dev#size in
672 let disks = List.map (fun {d_dev = dev} -> (dev :> device)) disks in
674 let rec loop ownership offset =
675 if offset < size then (
676 let devs, extent = get_next_extent disks dev offset in
678 eprintf "warning: no device found under %s\n"
679 (string_of_owner owner);
682 fun ownership (disk, disk_offset) ->
683 let elem = disk, (disk_offset, extent, owner, offset) in
686 loop ownership (offset +^ extent)
692 (* Return the length of the next contiguous region in the device starting
693 * at the given byte offset. Also return the underlying block device(s)
696 and get_next_extent disks (dev : device) offset =
697 let this_extent = dev#contiguous offset in
699 (* If this disk is a block_device (a member of the 'disks' list)
700 * then we've hit the bottom layer of devices, so just return it.
702 if List.memq dev disks then
703 [dev, offset], this_extent
705 let blocksize = dev#blocksize in
706 let block = offset /^ blocksize in
707 let offset_in_block = offset -^ block *^ blocksize in
709 (* Map from this block to the devices one layer down. *)
710 let devs = dev#map_block block in
712 (* Get the real device offsets, adding the offset from start of block. *)
715 (fun (dev, dev_offset) -> dev, dev_offset +^ offset_in_block)
720 (fun (dev, dev_offset) ->
721 get_next_extent disks dev dev_offset)
724 (* Work out the minimum contiguous extent from this offset. *)
726 let extents = List.map snd devs in
727 let devs = List.concat (List.map fst devs) in
728 let extent = List.fold_left min this_extent extents in
734 and string_of_owner = function
735 | `Filesystem {fs_cb = {fs_cb_name = name}; fs_dev = fs_dev} ->
736 sprintf "%s(%s)" fs_dev#name name
737 | `PhysicalVolume { pv_uuid = pv_uuid } ->
739 | `Partitions { parts_cb = {parts_cb_name = name} } ->
743 (* Build the list of segments. *)
744 let ownership : ownership_list = iter_over_machine machine in
746 (* Group the segments together by disk. *)
748 let ownership = List.sort ownership in
749 group_by ownership in
751 (* If debugging, print the segments that we found. *)
754 fun (disk, segments) ->
755 eprintf "ownership segment list of %s %s:\n" machine.m_name disk#name;
757 fun (disk_offset, size, owner, owner_offset) ->
758 let blocksize = disk#blocksize in
759 let disk_offset_in_blocks, disk_offset_in_block =
760 disk_offset /^ blocksize, disk_offset %^ blocksize in
761 let size_in_blocks, size_in_block =
762 size /^ blocksize, size %^ blocksize in
764 eprintf " %s[%s:%s] %s[%s:%s] %s@%s\n"
765 (Int63.to_string disk_offset)
766 (Int63.to_string disk_offset_in_blocks)
767 (Int63.to_string disk_offset_in_block)
768 (Int63.to_string size)
769 (Int63.to_string size_in_blocks)
770 (Int63.to_string size_in_block)
771 (string_of_owner owner)
772 (Int63.to_string owner_offset)
777 (* Build the segment tree from the ownership list (of segments).
778 * For an explanation of this process see:
779 * http://en.wikipedia.org/wiki/Segment_tree
783 fun (disk, segments) ->
784 (* Construct the list of distinct endpoints. *)
787 (fun (start, size, _, _) -> [start; start +^ size])
789 let eps = sort_uniq (List.concat eps) in
791 (* Construct the elementary intervals. *)
793 let elints, lastpoint =
795 fun (elints, prevpoint) point ->
796 ((point, point) :: (prevpoint, point) :: elints), point
797 ) ([], Int63.min_int) eps in
798 let elints = (lastpoint, Int63.max_int) :: elints in
802 eprintf "elementary intervals for %s (%d in total):\n"
803 disk#name (List.length elints);
805 fun (startpoint, endpoint) ->
807 (Int63.to_string startpoint) (Int63.to_string endpoint)
811 (* Construct the binary tree of elementary intervals. *)
813 (* Each elementary interval becomes a leaf. *)
814 let elints = List.map (fun elint -> Leaf elint) elints in
815 (* Recursively build this into a binary tree. *)
816 let rec make_layer = function
819 (* Turn pairs of leaves at the bottom level into nodes. *)
820 | (Leaf _ as a) :: (Leaf _ as b) :: xs ->
821 let xs = make_layer xs in
822 Node (a, (), b) :: xs
823 (* Turn pairs of nodes at higher levels into nodes. *)
824 | (Node _ as left) :: ((Node _|Leaf _) as right) :: xs ->
825 let xs = make_layer xs in
826 Node (left, (), right) :: xs
827 | Leaf _ :: _ -> assert false (* never happens??? (I think) *)
829 let rec loop = function
832 | xs -> loop (make_layer xs)
837 let leaf_printer (startpoint, endpoint) =
839 (Int63.to_string startpoint) (Int63.to_string endpoint)
841 let node_printer () = "" in
842 print_binary_tree leaf_printer node_printer tree
845 (* Insert the segments into the tree one by one. *)
847 (* For each node/leaf in the tree, add its interval and an
848 * empty list which will be used to store the segments.
850 let rec interval_tree = function
851 | Leaf elint -> Leaf (elint, [])
852 | Node (left, (), right) ->
853 let left = interval_tree left in
854 let right = interval_tree right in
855 let (leftstart, _) = interval_of_node left in
856 let (_, rightend) = interval_of_node right in
857 let interval = leftstart, rightend in
858 Node (left, (interval, []), right)
859 and interval_of_node = function
860 | Leaf (elint, _) -> elint
861 | Node (_, (interval, _), _) -> interval
864 let tree = interval_tree tree in
865 (* This should always be true: *)
866 assert (interval_of_node tree = (Int63.min_int, Int63.max_int));
868 (* "Contained in" operator.
869 * 'a <-< b' iff 'a' is a subinterval of 'b'.
871 * |<----------- b ----------->|
873 let (<-<) (a1, a2) (b1, b2) = b1 <= a1 && a2 <= b2 in
875 (* "Intersects" operator.
876 * 'a /\ b' iff intervals 'a' and 'b' overlap, eg:
878 * |<----------- b ----------->|
880 let ( /\ ) (a1, a2) (b1, b2) = a2 > b1 || b2 > a1 in
882 let rec insert_segment tree segment =
883 let start, size, owner, owner_offset = segment in
884 let seginterval = start, start +^ size in
885 let seg = owner, owner_offset in
888 (* Test if we should insert into this leaf or node: *)
889 | Leaf (interval, segs) when interval <-< seginterval ->
890 Leaf (interval, seg :: segs)
891 | Node (left, (interval, segs), right)
892 when interval <-< seginterval ->
893 Node (left, (interval, seg :: segs), right)
895 | (Leaf _) as leaf -> leaf
897 (* Else, should we insert into left or right subtrees? *)
898 | Node (left, i, right) ->
900 if seginterval /\ interval_of_node left then
901 insert_segment left segment
905 if seginterval /\ interval_of_node right then
906 insert_segment right segment
909 Node (left, i, right)
911 let tree = List.fold_left insert_segment tree segments in
915 let printer ((sp, ep), segments) =
916 sprintf "[%s-%s] " (Int63.to_string sp) (Int63.to_string ep) ^
918 (List.map (fun (owner,_) -> string_of_owner owner)
921 print_binary_tree printer printer tree
926 (* Return the ownership structure. *)
929 let get_owners_lookup machine ownership (disk : block_device) =
930 (* Get the correct tree. *)
931 let tree = List.assoc (disk :> device) ownership in
934 (* Warning: This 'hot' code was carefully optimized based on
935 * feedback from 'gprof'. Avoid fiddling with it.
937 let rec query = function
938 | Leaf (_, segments) -> segments
940 (* Try to avoid expensive '@' operator if node segments is empty: *)
941 | Node ((Leaf ((_, leftend), _) | Node (_, ((_, leftend), _), _) as left),
945 if offset < leftend then query left else query right in
948 (* ... or a singleton: *)
949 | Node ((Leaf ((_, leftend), _) | Node (_, ((_, leftend), _), _) as left),
953 if offset < leftend then query left else query right in
954 segment :: subsegments
956 (* Normal recursive case: *)
957 | Node ((Leaf ((_, leftend), _) | Node (_, ((_, leftend), _), _) as left),
961 if offset < leftend then query left else query right in
962 segments @ subsegments
964 let owners = query tree in
967 fun (owner, owner_offset) -> (owner, offset -^ owner_offset)
970 (* Find out if a disk offset is free.
971 * Current algorithm just checks that at least one owner says
972 * it is free. We could be smarter about this.
974 let offset_is_free owners =
977 | `Filesystem fs, offset ->
978 fs.fs_cb.fs_cb_offset_is_free fs offset
979 | `Partitions parts, offset ->
980 parts.parts_cb.parts_cb_offset_is_free parts offset
981 | `PhysicalVolume pv, offset ->
982 pv.pv_cb.lvm_cb_offset_is_free pv offset