First fallout of fd: migration - it looks like SELinux enforcing
_does_ require fd labeling (running uninstalled libvirtd from an
unconstrained shell had no problems, but once faked out by doing
chcon `stat -c %C /usr/sbin/libvirtd` daemon/libvirtd
run_init $PWD/daemon/libvirtd
to run it with the same context as an init script service, and with
SELinux enforcing, I got a rather confusing failure:
error: Failed to save domain fedora_12 to fed12.img
error: internal error unable to send TAP file handle: No file descriptor supplied via SCM_RIGHTS
This fixes the error message, then I need to figure out a subsequent
patch that does the fsetfilecon() necessary to keep things happy.
It also appears that libvirtd hangs on a failed fd transfer; I don't
know if that needs an independent fix.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextSendFileHandle):
Improve message, since TAP is no longer only client.
* src/Makefile.am src/libvirt_private.syms configure.ac: share and
reuse the sexpr routines from sexpr.h of the old xen driver
* src/libxl/libxl_driver.c: implements libxlDomainXMLFromNative and
libxlDomainXMLToNative
Hook the virtual cpu functions to their libxenlight counterparts
* src/libxl/libxl_driver.c: implements libxlDomainSetVcpus,
libxlDomainGetVcpus, libxlDomainSetVcpusFlags,
libxlDomainGetVcpusFlags and libxlDomainPinVcpu
* src/libxl/libxl_conf.h: add the necessary fields to the driver
private structure
* src/libxl/libxl_driver.c: add lifecycle event support and entry
points for event(de)register(any)
The daemon loops over the linked list of streams when a client
quits, closing any that the client hadn't already closed. Except
it didn't ever move to the next element in the list!
* daemon/stream.c: Fix loop over linked list of streams
The new commands vol-upload and vol-download, allow a local file
to be transferred to/from a storage volume.
* tools/virsh.c: Add vol-upload and vol-download commands
* tools/virsh.pod: Document new commands
New APIs are added allowing streaming of content to/from
storage volumes.
* include/libvirt/libvirt.h.in: Add virStorageVolUpload and
virStorageVolDownload APIs
* src/driver.h, src/libvirt.c, src/libvirt_public.syms: Stub
code for new APIs
* src/storage/storage_driver.c, src/esx/esx_storage_driver.c:
Add dummy entries in driver table for new APIs
The O_NONBLOCK flag doesn't work as desired on plain files
or block devices. Introduce an I/O helper program that does
the blocking I/O operations, communicating over a pipe that
can support O_NONBLOCK
* src/fdstream.c, src/fdstream.h: Add non-blocking I/O
on plain files/block devices
* src/Makefile.am, src/util/iohelper.c: I/O helper program
* src/qemu/qemu_driver.c, src/lxc/lxc_driver.c,
src/uml/uml_driver.c, src/xen/xen_driver.c: Update for
streams API change
The example C event loop code is a nasty hack and not compliant
with the require API semantics. Delete this, so that developers
don't mistakenly copy it. Instead call the new public event loop
APIs.
Update the python event loop example, so that it can optionally
use the public event APIs, as an alternative to the pure python
code. The pure python event code is a good working example, so
don't delete it.
Also make the python example use a read only connection to avoid
authentication prompts
* examples/domain-events/events-c/event-test.c: Replace event
loop code with use of public APIs
* examples/domain-events/events-python/event-test.py: Allow
optional use of new public event APIs
Spawn the compressor ourselves, instead of requiring the shell.
* src/qemu/qemu_migration.c (qemuMigrationToFile): Spawn
compression helper process when needed.
SELinux labeling and cgroup ACLs aren't required if we hand a
pre-opened fd to qemu. All the more reason to love fd: migration.
* src/qemu/qemu_migration.c (qemuMigrationToFile): Skip steps
that are irrelevant in fd migration.
This points out that core dumps (still) don't work for root-squash
NFS, since the fd is not opened correctly. This patch should not
introduce any functionality change, it is just a refactoring to
avoid duplicated code.
* src/qemu/qemu_migration.h (qemuMigrationToFile): New prototype.
* src/qemu/qemu_migration.c (qemuMigrationToFile): New function.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag, doCoreDump): Use
it.
Direct access to an open file is so much simpler than passing
everything through a pipe!
* src/qemu/qemu_driver.c (qemudOpenAsUID)
(qemudDomainSaveImageClose): Delete.
(qemudDomainSaveImageOpen): Rename...
(qemuDomainSaveImageOpen): ...and drop read_pid argument. Use
virFileOpenAs instead of qemudOpenAsUID.
(qemudDomainSaveImageStartVM, qemudDomainRestore)
(qemudDomainObjRestore): Rename...
(qemuDomainSaveImageStartVM, qemuDomainRestore)
(qemDomainObjRestore): ...and simplify accordingly.
(qemudDomainObjStart, qemuDriver): Update callers.
This patch intentionally doesn't change indentation, in order to
make it easier to review the real changes.
* src/util/util.h (VIR_FILE_OP_RETURN_FD, virFileOperationHook):
Delete.
(virFileOperation): Rename...
(virFileOpenAs): ...and reduce parameters.
* src/util/util.c (virFileOperationNoFork, virFileOperation):
Rename and simplify.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Adjust caller.
* src/storage/storage_backend.c (virStorageBackendCreateRaw):
Likewise.
* src/libvirt_private.syms: Reflect rename.
Currently, the hook function in virFileOperation is extremely limited:
it must be async-signal-safe, and cannot modify any memory in the
parent process. It is much handier to return a valid fd and operate
on it in the parent than to deal with hook restrictions.
* src/util/util.h (VIR_FILE_OP_RETURN_FD): New flag.
* src/util/util.c (virFileOperationNoFork, virFileOperation):
Honor new flag.
This allows direct saves (no compression, no root-squash NFS) to use
the more efficient fd: migration, which in turn avoids a race where
qemu exec: migration can sometimes fail because qemu does a generic
waitpid() that conflicts with the pclose() used by exec:. Further
patches will solve compression and root-squash NFS.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Use new function
when there is no compression.
Latent bug introduced in commit 2d6a581960 (Aug 2009), but not exposed
until commit 1859939a (Jan 2011). Basically, when virExec creates a
pipe, it always marks libvirt's side as cloexec. If libvirt then
wants to hand that pipe to another child process, things work great if
the fd is dup2()'d onto stdin or stdout (as with stdin: or exec:
migration), but if the pipe is instead used as-is (such as with fd:
migration) then qemu sees EBADF because the fd was closed at exec().
This is a minimal fix for the problem at hand; it is slightly racy,
but no more racy than the rest of libvirt fd handling, including the
case of uncompressed save images. A more invasive fix, but ultimately
safer at avoiding leaking unintended fds, would be to _always and
atomically_ open all fds as cloexec in libvirt (thanks to primitives
like open(O_CLOEXEC), pipe2(), accept4(), ...), then teach virExec to
clear that bit for all fds explicitly marked to be handed to the child
only after forking.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Clear cloexec
flag.
* tests/qemuxml2argvtest.c (testCompareXMLToArgvFiles): Tweak test.
* src/util/logging.c (virLogStartup, virLogSetBufferSize):
Over-allocate, so that a debugger can just print the circular
buffer. Suggested by Daniel Veillard.
* src/Makefile.am (remote_protocol-structs): Flatten tabs.
* src/remote_protocol-structs: Likewise. Also add a hint to emacs
to make it easier to keep spaces in the file.
Diego reported a bug where virsh tries to initialize a readline
history directory during 'make check' run as root, but fails
because /root was read-only.
It turns out that I could reproduce this as non-root, by using:
mv ~/.virsh{,.bak}
chmod a-w ~
make check -C tests TESTS=int-overflow
chmod u+w ~
mv ~/.virsh{.bak,}
* tests/int-overflow: Don't trigger interactive mode.
Reported by Diego Elio Pettenò.
Otherwise, if something like doStopVcpus fails after the first
restore, a second restore is attempted and throws a useless
warning.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Avoid second
restore of state label.
The Open Nebula driver has been unmaintained since it was first
introduced. The only commits have been for tree-wide cleanups.
It also has a major design flaw, in that it only knows about guests
that it has created itself, which makes it of very limited use.
Discussions wrt evolution of the VMWare ESX driver, concluded that
it should limit itself to single-node ESX operation and not try to
manage the multi-node architecture of VirtualCenter. Open Nebula
is a cluster like Virtual Center, not a single node system, so
the same reasoning applies.
The DeltaCloud project includes an Open Nebula driver and is a much
better fit architecturally, since it is explicitly targetting the
distributed multihost cluster scenario.
Thus this patch deletes the libvirt Open Nebula driver with the
recommendation that people use DeltaCloud for managing it instead.
* configure.ac: Remove probe for xmlrpc & --with-one arg
* daemon/Makefile.am, daemon/libvirtd.c, src/Makefile.am: Remove
ONE driver build
* src/opennebula/one_client.c, src/opennebula/one_client.h,
src/opennebula/one_conf.c, src/opennebula/one_conf.h,
src/opennebula/one_driver.c, src/opennebula/one_driver.c: Delete
files
* autobuild.sh, libvirt.spec.in, mingw32-libvirt.spec.in: Remove
build rules for Open Nebula
* docs/drivers.html.in, docs/sitemap.html.in: Remove reference
to OpenNebula
* docs/drvone.html.in: Delete file
Some things to note in this patch:
- we do extend libvirt scope beyond purely managing domains, there is
already a number of blocks which are here as helpr functions to
manage the resources on the host.
- we are expanding in the direction of libvirt being sufficient to do
most of the management on the Host (but within the limits of the need
for virtualization, e.g. managing users on the host is out of scope)
- we don't require anymore APIs to be supported by multiple
hypervisors to get in, it's already the case in practice, but we
should still make sure the semantic of those APIs are clear. We
added quite a bit for QEmu, but for example I saw on IRC that VBox
could emulate a network unplug/replug on a domain interface, and
that would be a good addition even if a priori no other hypervisor
supports it.
- Make clear that all libvirt APIs are available remotely, which is
key to use libvirt for building management tools.
- link the goal page from the project main page
As for libvirt project directions, I think it just reflects the natural
evolution in the last couple of years. We are less hypervisor agnostic
and extending in the Host management. Clearly there is interest in
making sure libvirt is complete in term of features for the hypervisors
supported, especially the ones like KVM or LXC which don't really have
integrated management library.
* docs/goals.html.in: update the goals page
* docs/index.html.in: link it from the top page
Add missing open curly brace between function declaration of non-linux
variant of qemudDomainInterfaceStats() and its body.
Signed-off-by: Philipp Hahn <hahn@univention.de>
Commit f44bfb7 was supposed to make sure no additional libvirt API (esp.
*Free) is called before remoteDispatchConnError() is called on error.
However, the patch missed two instances.
Sometimes, an asynchronous helper is started (such as a compressor
or iohelper program), but a later error means that we want to
abort that child. Make this easier.
Note that since daemons and virCommandRunAsync can't mix, the only
time virCommandFree can reap a process is if someone did
virCommandRunAsync for a non-daemon and didn't stash the pid.
* src/util/command.h (virCommandAbort): New prototype.
* src/util/command.c (_virCommand): Add new field.
(virCommandRunAsync, virCommandWait): Track whether pid was used.
(virCommandFree): Reap child if caller did not request pid.
(virCommandAbort): New function.
* src/libvirt_private.syms (command.h): Export it.
* tests/commandtest.c (test19): New test.
It doesn't make sense to run a daemon without synchronously
waiting for the child process to reply whether the daemon has
been kicked off and pidfile written yet.
* src/util/command.c (VIR_EXEC_RUN_SYNC): New constant.
(virCommandRun): Set temporary flag.
(virCommandRunAsync): Use it to prevent async runs of intermediate
child when spawning asynchronous daemon grandchild.
Child processes don't always reach _exit(); if they die from a
signal, then any messages should still be accurate. Most users
either expect a 0 status (thankfully, if status==0, then
WIFEXITED(status) is true and WEXITSTATUS(status)==0 for all
known platforms) or were filtering on WIFEXITED before printing
a status, but a few were missing this check. Additionally,
nwfilter_ebiptables_driver was making an assumption that works
on Linux (where WEXITSTATUS shifts and WTERMSIG just masks)
but fails on other platforms (where WEXITSTATUS just masks and
WTERMSIG shifts).
* src/util/command.h (virCommandTranslateStatus): New helper.
* src/libvirt_private.syms (command.h): Export it.
* src/util/command.c (virCommandTranslateStatus): New function.
(virCommandWait): Use it to also diagnose status from signals.
* src/security/security_apparmor.c (load_profile): Likewise.
* src/storage/storage_backend.c
(virStorageBackendQEMUImgBackingFormat): Likewise.
* src/util/util.c (virExecDaemonize, virRunWithHook)
(virFileOperation, virDirCreate): Likewise.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c (ebiptablesExecCLI):
Likewise.
Eric Blake