This adds the systemd xen service / module files and integrates
support into the build system.
This goes in with AX_AVAILABLE_SYSTEMD() which will enable
systemd if development libraries have been found on your
build system. If you don't have systemd on target systems
for binaries built with systemd then the binary will not
work, you must explicitly disable systemd support if you
do not want to build systemd support.
When systemd libraries are present only systems that
have booted into systemd go through the systemd initialization,
otherwise the SysVinit is used.
These are originally based on the Fedora systemd files.
Changes made from Fedora's systemd files:
* split sockets into two files to claim different permissions
* Use /bin/sh -c exec to for a simple launcher implementation
* enables systemd socket activation for C xenstored and Ocaml
oxenstored
* use sd_notify(), so change the service to Type=notify, because of
this we remove the PIDFile specification as we don't care for it, and let
systemd do its magic for us, this also means we don't have to fork
so we use --no-fork with systemd
* defines a modules-load.d, its original source file will be shared
between systemd and old init systems
* simplify service files with ConditionVirtualization=xen which uses
the built in systemd virtualization backend detection, these
service files will not be available to start on systems that do not
boot with xen as a hypervisor
* use autoconf to replace @variable@ paths for us which piggy
backs on top of the latest autoconf changes to xen
* removes oxenstored service file in favor of a system variable which
controls which which xentored to use at run time, we avoid multiple
service files this way.
* simplifies startup to not require polling on the sockets
as initial socket management is handled by systemd, we just
take on the socket later once anything pokes at it, a simple nc -U
(as root) on any of the sockets files can activate the service for example.
Anything queued up will be sent to us once we start. Socket activation
should in theory also let us dynamically switch between xenstores but more
importantly we could upgrade xenstored while keeping all active
socket communication queued up, but in order to take advantage of
this we eventually would need to remove the requirement of not being
able to bring down the xenstored. Even though active sockets are
supported since most libxl communication doesn't triggger a check
on the unix socket first administrators are encouraged to enable
the xenstored.service to triggger an initialization of the xenstored
upon bring up. Some systems also never use unix sockets for
communication with the xenstored and as such active sockets will
not be used there.
* allow for xenstored configuration through *either* of these
configuration files:
- /etc/sysconfig/xenstored
- /etc/default/xenstored
The /etc/default/xenstored will let debian based systems do
the same, while SUSE/OpenSUSE/Fedora/RedHat can keep on chugging
with sysconfig. We leave these files all commented out by default
though given that for systemd we want to encourage not using them.
* ensures we create the run directory as most systems will likely
be using a tmpfs for run dirs for the pid files
* Some systems define the selinux context in the systemd Option for the
/var/lib/xenstored tmpfs:
Options=mode=755,context="system_u:object_r:xenstored_var_lib_t:s0"
For the upstream version we remove that and let systems specify the
context on their system /etc/default/xenstored or /etc/sysconfig/xenstored
$XENSTORED_MOUNT_CTX variable, with a default to none.
* takes advantage of the shared xendomains helper for the xendomains
service
* Add the new dom0 that gets kicked off for disk backend access into
its own systemd service associated to xen
We end up with these systemd files:
General requirements:
* proc-xen.mount
* var-lib-xenstored.mount
xenstored:
* xenstored.service
* xenstored.socket
* xenstored_ro.socket
* xenconsoled.service
* xen-qemu-dom0-disk-backend.service.in
Optional:
* xendomains.service
* xen-watchdog.service
As for integration with xen, we house keep all the systemd files
under a new directory tools/hotplug/Linux/systemd/ and will be targeted
by default when building on Linux systems if systemd development
libraries are present at build time.
The systemd files will be sanitized for meta @VARIABLES@ upon
configuration and installed upon the install target. Systems that
do not use systemd can still get systemd service unit files installed
if the build system enabled systemd support, this however does not
mandate a requirement of having systemd libraries present. Old init
scripts are always installed.
If you don't specify a prefix you will end up with the services
files under /usr/local/lib/systemd/system/ by default, and systemd
modules-load.d conf files under /usr/local/lib/modules-load.d/ which
systemd does look for (although it seems this is not documented).
Distributions are expected to provide their /usr/ prefix to end up in
the more generic location upon distribution install at
/usr/lib/systemd/system/ and /usr/lib/modules-load.d/ respectively.
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jan Rękorajski <baggins@pld-linux.org>
Cc: M A Young <m.a.young@durham.ac.uk>
Cc: Jacek Konieczny <jajcus@jajcus.net>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- ran autogen.sh ]
This adds systemd socket activation support for the Ocaml xenstored.
Ocaml lacks systemd library support so we provide our own C helpers
as is done with other functionality lacking on Ocaml.
Active sockets enables oxenstored to be loaded only if required by a system
onto which Xen is installed on. Socket activation is handled by
systemd, once a port for a service which claims a socket is used
systemd will start the required services for it, on demand. For more
details on socket activation refer to Lennart's socket-activation
post regarding this [0].
An important difference with socket activation is that systemd will set
FD_CLOEXEC for us on the socket before giving it to us, we'll sprinkly
the Unix.set_close_on_exec for LSB init next as a separate commit.
Right now this code adds a no-op for this functionality, leaving the
enablement to be done later once systemd is properly hooked into
the build system. The socket activation is ordered in aligment with
the socket activation order passed on to systemd.
[0] http://0pointer.de/blog/projects/socket-activation2.html
Cc: David Scott <dave.scott@eu.citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Vincent Hanquez <Vincent.Hanquez@eu.citrix.com>
Acked-by: Dave Scott <Dave.Scott@citrix.com>
Acked-by: Anil Madhavapeddy <anil@recoil.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
This will be used later for dynamic configuration paths on C code.
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
At a beginning of a transaction, the quotas from the global store
are duplicated and modified by the transaction. If during the
transaction, an action associated to no transaction is concurrently
executed, the quotas of the global store are updated, and then the
updates are lost when the transaction merges.
We fix this problem by keeping another copy of the quota at the
beginning of the transaction, and performing a 3-way merge between
the quotas from the transaction and the "original" copy of the quota
onto the quota of the global store.
Signed-off-by: Jerome Maloberti <jerome.maloberti@citrix.com>
Signed-off-by: Euan Harris <euan.harris@citrix.com>
Acked-by: David Scott <dave.scott@citrix.com>
If a domU has exhausted its quota we still want the toolstack in dom0 to
be able to create new nodes in places like
/local/domain/%d/control/shutdown
Without this patch, a domU which has exhausted its quota can only be
powered off, which is not as good as being able to request a clean
shutdown.
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Signed-off-by: Euan Harris <euan.harris@citrix.com>
Acked-by: David Scott <dave.scott@citrix.com>
Toolstacks may specify a VM generation ID using the u.hvm.ms_vm_genid
field in the libxl_domain_build_info structure, when creating a
domain.
The toolstack is responsible for providing the correct generation ID
according to the Microsoft specification (e.g., generating new random
ones with libxl_ms_vm_genid_generate() as appropriate when restoring).
Although the specification requires that a ACPI Notify event is raised
if the generation ID is changed, the generation ID is never changed
when the domain is in a state to receive such an event (it's either
newly created or suspended).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: David Scott <dave.scott@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
by using the flag and the new cpumap arguments introduced in
the parameters of the DOMCTL_{get,set}_vcpuaffinity hypercalls.
Now, both xc_vcpu_setaffinity() and xc_vcpu_getaffinity() have
a new flag parameter, to specify whether the user wants to
set/get hard affinity, soft affinity or both. They also have
two cpumap parameters instead of only one. This way, it is
possible to set/get both hard and soft affinity at the same
time (and, in case of set, each one to its own value).
In xc_vcpu_setaffinity(), the cpumaps are IN/OUT parameters,
as it is for the corresponding arguments of the
DOMCTL_set_vcpuaffinity hypercall. What Xen puts there is the
hard and soft effective affinity, that is what Xen will actually
use for scheduling.
In-tree callers are also fixed to cope with the new interface.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The various cpuid functions are not available on ARM, so this
makes them raise an OCaml exception. Omitting the functions
completely results in a link failure in oxenstored due to the
missing symbols, so this is preferable to the much bigger patch
that would result from adding conditional compilation into the
OCaml interfaces.
With this patch, oxenstored can successfully start a domain on
Xen/ARM.
Signed-off-by: Anil Madhavapeddy <anil@recoil.org>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This allows the application to pass a token to libxl in the fd/timeout
registration callbacks, which it receives back in modification or
deregistration callbacks.
It turns out that this is essential for timeout handling, in order to
identify which timeout to change on a modify event.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
The original code works fine on 64-bit, but on 32-bit, the OCaml int (which is
1 bit smaller than the C int) is likely to overflow.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Ocaml has a heap lock which must be held whenever ocaml code is running. Ocaml
usually drops this lock when it enters a potentially blocking low-level
function, such as writing to a file. Libxl has its own lock, which it may
acquire when being called.
Things get interesting when libxl calls back into ocaml code. There is a risk
of ending up in a deadlock when a thread holds both locks at the same time,
then temporarily drop the ocaml lock, while another thread calls another libxl
function.
To avoid deadlocks, we drop the ocaml heap lock before entering libxl, and
reacquire it in callbacks to ocaml. This way, the ocaml heap lock is never held
together with the libxl lock, except in osevent registration callbacks, and
xentoollog callbacks. If we guarantee to not call any libxl functions inside
those callbacks, we can avoid deadlocks.
This patch handle the dropping and reacquiring of the ocaml heap lock by the
caml_enter_blocking_section and caml_leave_blocking_section functions, and
related macros. We are also careful to not call any functions that access the
ocaml heap while the ocaml heap lock is dropped. This often involves copying
ocaml values to C before dropping the ocaml lock.
The ao_how in aohow_val is now malloc'ed, just to make this function a little
easier to use.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Also:
* Reorganise toplevel OCaml functions into modules of Xenlight.
* Factor out the management of ao_how into the function aohow_val. The ao_how
is now malloc'ed, just to make this function a little easier to use.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Having bindings to the low-level functions libxl_osevent_register_hooks and
related, allows to run an event loop in OCaml; either one we write ourselves,
or one that is available elsewhere.
The Lwt cooperative threads library (http://ocsigen.org/lwt/), which is quite
popular these days, has an event loop that can be easily extended to poll any
additional fds that we get from libxl. Lwt provides a "lightweight" threading
model, which does not let you run any other (POSIX) threads in your
application, and therefore excludes an event loop implemented in the C
bindings.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Allow a domain updating existing xenstore keys even if it has already reached
its max entries limit
As updating existing key won't increase the number of entries belonging to a
domain, we should avoid checking the max entries limit prematurely. The patch
addresses this issue in the following functions: write/add, mkdir, setperms.
Signed-off-by: Zheng Li <zheng.li@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Libxl functions such as libxl_domain_create_new take large structs
of configuration parameters. Often, we would like to use the default
values for many of these parameters.
The struct and keyed-union types in libxl have init functions, which
fill in the defaults for a given type. This commit provides an OCaml
interface to obtain records of defaults by calling the relevant init
function.
These default records can be used as a base to construct your own
records, and to selectively override parameters where needed.
For example, a Domain_create_info record can now be created as follows:
Xenlight.Domain_create_info.({ default ctx () with
ty = Xenlight.DOMAIN_TYPE_PV;
name = Some vm_name;
uuid = vm_uuid;
})
For types with KeyedUnion fields, such as Domain_build_info, a record
with defaults is obtained by specifying the type key:
Xenlight.Domain_build_info.default ctx ~ty:Xenlight.DOMAIN_TYPE_HVM ()
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The libxl IDL is based on C type "char *", and therefore "strings" can
by NULL, or be an actual string. In ocaml, it is common to encode such
things as option types.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
In order to avoid newly created OCaml values from being GC'ed, they must be
registered as roots with the GC, before an iteration of the GC may happen. The
Val_* functions potentially allocate new values on the OCaml heap, and may
trigger an iteration of the OCaml GC.
The way to register a value with the GC is to assign it to a variable declared
with a CAMLparam or CAMLlocal macro, which put the value into a struct that
can be reached from a GC root.
This leads to slightly weird looking C code, but avoids hard to find segfaults.
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Since the context has a logger we can get rid of the logger built into these
bindings and use the xentoollog bindings instead.
The gc is of limited use when most things are freed with libxl_FOO_dispose,
so get rid of that too.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Rather than allocating a new context for every libxl call begin to
switch to a model where a context is allocated by the caller and may
then be used for multiple calls down into the library.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
These bindings allow ocaml code to receive log message via xentoollog
but do not support injecting messages into xentoollog from ocaml.
Receiving log messages from libx{c,l} and forwarding them to ocaml is
the use case which is needed by the following patches.
Add a simple noddy test case (tools/ocaml/test).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
[ ijc -- dropped the xtl test harness, it failed to link ]
* bitmaps
* string_list
* key_value_list
* cpuid_policy_list (left "empty" for now)
None of these are used yet, so no change to the generated code.
Bitmap_val requires a ctx, so leave it as an abort for now.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
A KeyedUnion consists of two fields in the containing struct. First an
enum field ("e") used as a descriminator and second a union ("u")
containing potentially anonymous structs associated with each enum
value.
We map the anonymous structs to structs named after the descriminator
field ("e") and the specific enum values. We then declare an ocaml
variant type name e__union mapping each enum value to its associated
struct.
So given IDL:
foo = Enumeration("foo", [
(0, "BAR"),
(1, "BAZ"),
])
s = Struct("s", [
("u", KeyedUnion(none, foo, "blargle", [
("bar", Struct(...xxx...)),
("baz", Struct(...yyy...)),
])),
])
We generate C:
enum foo { BAR, BAZ };
struct s {
enum foo blargle;
union {
struct { ...xxx... } bar;
struct { ...yyy... } baz;
} u;
}
and map this to ocaml
type foo = BAR | BAZ;
module S = struct
type blargle_bar = ...xxx...;
type blargle_baz = ...yyy...;
type blargle__union = Bar of blargle_bar | Baz of blargle_baz;
type t =
{
blargle : blargle__union;
}
end
These type names are OK because they are already within the namespace
associated with the struct "s".
If the struct associated with bar is empty then we don't bother with
blargle_bar of "of blargle_bar".
No actually change in the generated code since we don't generate any
KeyedUnions yet.
The actual implementation was inspired by
http://www.linux-nantes.org/~fmonnier/ocaml/ocaml-wrapping-c.php#ref_constvrnt
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
This fixes the issue for both C and ocaml xenstored, however only the ocaml
xenstored is vulnerable in its default configuration.
Adding a new error appears to be safe, since bit libxenstore and the Linux
driver at least treat an unknown error code as EINVAL.
This is XSA-72 / CVE-2013-4416.
Original ocaml patch by Jerome Maloberti <jerome.maloberti@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Not sure how it got there...
Coverity-ID: 1056196
This is CVE-2013-4370 / XSA-69
Signed-off-by: Matthew Daley <mattjd@gmail.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
add check logic when read from IO ring, and if error happens,
then mark the reading connection as "bad", Unless vm reboot,
oxenstored will not handle message from this connection any more.
xs_ring_stubs.c: add a more strict check on ring reading
connection.ml, domain.ml: add getter and setter for bad flag
process.ml: if exception raised when reading from domain's ring,
mark this domain as "bad"
xenstored.ml: if a domain is marked as "bad", do not handle it.
Signed-off-by: John Liu <john.liuqiming@huawei.com>
Acked-by: David Scott <dave.scott@eu.citrix.com>
Luis R. Rodriguez
Jerome Maloberti
Vincent Bernardoff
David Vrabel
Dario Faggioli
Don Slutz
Anil Madhavapeddy
Rob Hoes
Zheng Li
Ian Jackson
Matthew Daley
=John Liu