1 (** 'df' command for virtual domains. *)
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.
20 (** This module (Virt_df) contains functions and values which are
21 used throughout the plug-ins and main code.
24 val ( +* ) : int32 -> int32 -> int32
25 val ( -* ) : int32 -> int32 -> int32
26 val ( ** ) : int32 -> int32 -> int32
27 val ( /* ) : int32 -> int32 -> int32
28 val ( +^ ) : int64 -> int64 -> int64
29 val ( -^ ) : int64 -> int64 -> int64
30 val ( *^ ) : int64 -> int64 -> int64
31 val ( /^ ) : int64 -> int64 -> int64
32 (** int32 and int64 infix operators for convenience. *)
34 val debug : bool ref (** If true, emit debug info to stderr*)
35 val uri : string option ref (** Hypervisor/libvirt URI. *)
36 val inodes : bool ref (** Display inodes. *)
37 val human : bool ref (** Display human-readable. *)
38 val all : bool ref (** Show all or just active domains. *)
39 val test_files : string list ref (** In test mode (-t) list of files. *)
40 (** State of command line arguments. *)
43 {2 Domain/device model}
45 The "domain/device model" that we currently understand looks
51 \--- host partitions / disk image files
55 +--> guest partitions (eg. using MBR)
57 \-(1)->+--- filesystems (eg. ext3)
64 (1) Filesystems and PVs may also appear directly on guest
67 Partition schemes (eg. MBR) and filesystems register themselves
68 with this main module and they are queried first to get an idea
69 of the physical devices, partitions and filesystems potentially
70 available to the guest.
72 Volume management schemes (eg. LVM2) register themselves here
73 and are called later with "spare" physical devices and partitions
74 to see if they contain LVM data. If this results in additional
75 logical volumes then these are checked for filesystems.
77 Swap space is considered to be a dumb filesystem for the purposes
81 class virtual device :
83 method virtual name : string
84 method virtual read : int64 -> int -> string
85 method read_bitstring : int64 -> int -> string * int * int
86 method virtual size : int64
89 A virtual (or physical!) device, encapsulating any translation
90 that has to be done to access the device. eg. For partitions
91 there is a simple offset, but for LVM you may need complicated
94 We keep the underlying file descriptors open for the duration
95 of the program. There aren't likely to be many of them, and
96 the program is short-lived, and it's easier than trying to
97 track which device is using what fd. As a result, there is no
98 need for any close/deallocation function.
100 Note the very rare use of OOP in OCaml!
103 class block_device : string ->
106 method read : int64 -> int -> string
107 method read_bitstring : int64 -> int -> string * int * int
110 (** A concrete device which just direct-maps a file or /dev device. *)
112 class offset_device : string -> int64 -> int64 -> device ->
115 method read : int64 -> int -> string
116 method read_bitstring : int64 -> int -> string * int * int
119 (** A concrete device which maps a linear part of an underlying device.
121 [new offset_device name start size dev] creates a new
122 device which maps bytes from [start] to [start+size-1]
123 of the underlying device [dev] (ie. in this device they
124 appear as bytes [0] to [size-1]).
126 Useful for things like partitions.
129 val null_device : device
130 (** The null device. Any attempt to read generates an error. *)
133 dom_name : string; (** Domain name. *)
134 dom_id : int option; (** Domain ID (if running). *)
135 dom_disks : disk list; (** Domain disks. *)
137 (lv * filesystem) list; (** Domain LV filesystems. *)
140 d_type : string option; (** The <disk type=...> *)
141 d_device : string; (** The <disk device=...> (eg "disk") *)
142 d_source : string; (** The <source file=... or dev> *)
143 d_target : string; (** The <target dev=...> (eg "hda") *)
144 d_dev : device; (** Disk device. *)
145 d_content : disk_content; (** What's on it. *)
148 [ `Filesystem of filesystem (** Contains a direct filesystem. *)
149 | `Partitions of partitions (** Contains partitions. *)
150 | `PhysicalVolume of pv (** Contains an LVM PV. *)
151 | `Unknown (** Not probed or unknown. *)
154 parts_name : string; (** Name of partitioning scheme. *)
155 parts : partition list; (** Partitions. *)
158 part_status : partition_status; (** Bootable, etc. *)
159 part_type : int; (** Partition filesystem type. *)
160 part_dev : device; (** Partition device. *)
161 part_content : partition_content; (** What's on it. *)
163 and partition_status = Bootable | Nonbootable | Malformed | NullEntry
164 and partition_content =
165 [ `Filesystem of filesystem (** Filesystem. *)
166 | `PhysicalVolume of pv (** Contains an LVM PV. *)
167 | `Unknown (** Not probed or unknown. *)
170 fs_name : string; (** Name of filesystem. *)
171 fs_block_size : int64; (** Block size (bytes). *)
172 fs_blocks_total : int64; (** Total blocks. *)
173 fs_is_swap : bool; (** If swap, following not valid. *)
174 fs_blocks_reserved : int64; (** Blocks reserved for super-user. *)
175 fs_blocks_avail : int64; (** Blocks free (available). *)
176 fs_blocks_used : int64; (** Blocks in use. *)
177 fs_inodes_total : int64; (** Total inodes. *)
178 fs_inodes_reserved : int64; (** Inodes reserved for super-user. *)
179 fs_inodes_avail : int64; (** Inodes free (available). *)
180 fs_inodes_used : int64; (** Inodes in use. *)
183 lvm_plugin_id : lvm_plugin_id; (** The LVM plug-in which detected
185 pv_uuid : string; (** UUID. *)
188 lv_dev : device; (** Logical volume device. *)
193 val string_of_partition : partition -> string
194 val string_of_filesystem : filesystem -> string
195 (** Convert a partition or filesystem struct to a string (for debugging). *)
197 val canonical_uuid : string -> string
198 (** Convert a UUID which may contain '-' characters to canonical form. *)
200 (** {2 Plug-in registration functions} *)
202 val partition_type_register : string -> (device -> partitions) -> unit
203 (** Register a partition probing plug-in. *)
205 val probe_for_partitions : device -> partitions option
206 (** Do a partition probe on a device. Returns [Some partitions] or [None]. *)
208 val filesystem_type_register : string -> (device -> filesystem) -> unit
209 (** Register a filesystem probing plug-in. *)
211 val probe_for_filesystem : device -> filesystem option
212 (** Do a filesystem probe on a device. Returns [Some filesystem] or [None]. *)
214 val lvm_type_register :
215 string -> (lvm_plugin_id -> device -> pv) -> (device list -> lv list) -> unit
216 (** [lvm_type_register lvm_name probe_fn list_lvs_fn]
217 registers a new LVM type. [probe_fn] is a function which
218 should probe a device to find out if it contains a PV.
219 [list_lvs_fn] is a function which should take a list of
220 devices (PVs) and construct a list of LV devices.
223 val probe_for_pv : device -> pv option
224 (** Do a PV probe on a device. Returns [Some pv] or [None]. *)
226 val list_lvs : lvm_plugin_id -> device list -> lv list
227 (** Construct LV devices from a list of PVs. *)
229 (** {2 Utility functions} *)
231 val group_by : ?cmp:('a -> 'a -> int) -> ('a * 'b) list -> ('a * 'b list) list
232 (** Group a sorted list of pairs by the first element of the pair. *)
234 val range : int -> int -> int list
235 (** [range a b] returns the list of integers [a <= i < b].
236 If [a >= b] then the empty list is returned.