The xenHypervisorInit method was called from two different
locations, during initial driver registration and also while
opening a Xen connection. The former can't report any useful
errors to the end user/app, so remove it. To ensure thread
safety use a VIR_ONCE_GLOBAL_INIT call to invoke
xenHypervisorInit from the xenHypervisorOpen method.
As per the comment, the Xen hypervisor driver is considered to
be mandatory when running privileged. When it fails to open,
we should thus return an error, not ignore it.
Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:
List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' | \
grep -e '\.[ch]$' -e '\.py$'
Found files were modified with this command:
sed -i -e \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'
Then checked for nonsense.
The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' | \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'
On 64-bit platforms, unsigned long and unsigned long long are
identical, so we don't have to worry about overflow checks.
On 32-bit platforms, anywhere we narrow unsigned long long back
to unsigned long, we have to worry about overflow; it's easier
to do this in one place by having most of the code use the same
or wider types, and only doing the narrowing at the last minute.
Therefore, the memory set commands remain unsigned long, and
the memory get command now centralizes the overflow check into
libvirt.c, so that drivers don't have to repeat the work.
This also fixes a bug where xen returned the wrong value on
failure (most APIs return -1 on failure, but getMaxMemory
must return 0 on failure).
* src/driver.h (virDrvDomainGetMaxMemory): Use long long.
* src/libvirt.c (virDomainGetMaxMemory): Raise overflow.
* src/test/test_driver.c (testGetMaxMemory): Fix driver.
* src/rpc/gendispatch.pl (name_to_ProcName): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetMaxMemory): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetMaxMemory): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xend_internal.h (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xm_internal.c (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xm_internal.h (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.c (xenStoreDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.h (xenStoreDomainGetMaxMemory): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainGetMaxMemory):
Likewise.
* src/esx/esx_driver.c (esxDomainGetMaxMemory): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetMaxMemory): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetMaxMemory): Likewise.
* src/lxc/lxc_driver.c (lxcDomainGetMaxMemory): Likewise.
* src/uml/uml_driver.c (umlDomainGetMaxMemory): Likewise.
Function xmlParseURI does not remove square brackets around IPv6
address when parsing. One of the solutions is making wrappers around
functions working with xmlURI*. This assures that uri->server will be
always properly assigned and it doesn't have to be changed when used
on some new place in the code.
For this purpose, functions virParseURI and virSaveURI were
added. These function are wrappers around xmlParseURI and xmlSaveUri
respectively.
Also there is one new syntax check function to prohibit these functions
anywhere else.
File changes:
- src/util/viruri.h -- declaration
- src/util/viruri.c -- definition
- src/libvirt_private.syms -- symbol export
- src/Makefile.am -- added source and header files
- cfg.mk -- added sc_prohibit_xmlURI
- all others -- ID name and include fixes
The auto-generated WWN comply with the new addressing schema of WWN:
<quote>
the first nibble is either hex 5 or 6 followed by a 3-byte vendor
identifier and 36 bits for a vendor-specified serial number.
</quote>
We choose hex 5 for the first nibble. And for the 3-bytes vendor ID,
we uses the OUI according to underlying hypervisor type, (invoking
virConnectGetType to get the virt type). e.g. If virConnectGetType
returns "QEMU", we use Qumranet's OUI (00:1A:4A), if returns
ESX|VMWARE, we use VMWARE's OUI (00:05:69). Currently it only
supports qemu|xen|libxl|xenapi|hyperv|esx|vmware drivers. The last
36 bits are auto-generated.
libvirt supports 4 different versions of the user-land XenD daemon. When
queried the daemon just returns its generation number, which is hard to
match to the version of the Xen tools.
Replace the magic generation numbers by named enum definitions to
improve code readability.
Signed-off-by: Philipp Hahn <hahn@univention.de>
Add a new API virDomainShutdownFlags and define:
VIR_DOMAIN_SHUTDOWN_DEFAULT = 0,
VIR_DOMAIN_SHUTDOWN_ACPI_POWER_BTN = (1 << 0),
VIR_DOMAIN_SHUTDOWN_GUEST_AGENT = (1 << 1),
Also define some flags for the reboot API
VIR_DOMAIN_REBOOT_DEFAULT = 0,
VIR_DOMAIN_REBOOT_ACPI_POWER_BTN = (1 << 0),
VIR_DOMAIN_REBOOT_GUEST_AGENT = (1 << 1),
Although these two APIs currently have the same flags, using
separate enums allows them to expand separately in the future.
Add stub impls of the new API for all existing drivers
pciTrySecondaryBusReset checks if there is active device on the
same bus, however, qemu driver doesn't maintain an effective
list for the inactive devices, and it passes meaningless argument
for parameter "inactiveDevs". e.g. (qemuPrepareHostdevPCIDevices)
if (!(pcidevs = qemuGetPciHostDeviceList(hostdevs, nhostdevs)))
return -1;
..skipped...
if (pciResetDevice(dev, driver->activePciHostdevs, pcidevs) < 0)
goto reattachdevs;
NB, the "pcidevs" used above are extracted from domain def, and
thus one won't be able to attach a device of which bus has other
device even detached from host (nodedev-detach). To see more
details of the problem:
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=773667
This patch is to resolve the problem by introducing an inactive
PCI device list (just like qemu_driver->activePciHostdevs), and
the whole logic is:
* Add the device to inactive list during nodedev-dettach
* Remove the device from inactive list during nodedev-reattach
* Remove the device from inactive list during attach-device
(for non-managed device)
* Add the device to inactive list after detach-device, only
if the device is not managed
With the above, we have a sufficient inactive PCI device list, and thus
we can use it for pciResetDevice. e.g.(qemuPrepareHostdevPCIDevices)
if (pciResetDevice(dev, driver->activePciHostdevs,
driver->inactivePciHostdevs) < 0)
goto reattachdevs;
The lifetime of the virDomainEventState object is tied to
the lifetime of the driver, which in stateless drivers is
tied to the lifetime of the virConnectPtr.
If we add & remove a timer when allocating/freeing the
virDomainEventState object, we can get a situation where
the timer still triggers once after virDomainEventState
has been freed. The timeout callback can't keep a ref
on the event state though, since that would be a circular
reference.
The trick is to only register the timer when a callback
is registered with the event state & remove the timer
when the callback is unregistered.
The demo for the bug is to run
while true ; do date ; ../tools/virsh -q -c test:///default 'shutdown test; undefine test; dominfo test' ; done
prior to this fix, it will frequently hang and / or
crash, or corrupt memory
Currently all drivers using domain events need to provide a callback
for handling a timer to dispatch events in a clean stack. There is
no technical reason for dispatch to go via driver specific code. It
could trivially be dispatched directly from the domain event code,
thus removing tedious boilerplate code from all drivers
Also fix the libxl & xen drivers to pass 'true' when creating the
virDomainEventState, since they run inside the daemon & thus always
expect events to be present.
* src/conf/domain_event.c, src/conf/domain_event.h: Internalize
dispatch of events from timer callback
* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
src/qemu/qemu_domain.c, src/qemu/qemu_driver.c,
src/remote/remote_driver.c, src/test/test_driver.c,
src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
src/xen/xen_driver.c: Remove all timer dispatch functions
When registering a callback for a particular event some callers
need to know how many callbacks already exist for that event.
While it is possible to ask for a count, this is not free from
race conditions when threaded. Thus the API for registering
callbacks should return the count of callbacks. Also rename
virDomainEventStateDeregisterAny to virDomainEventStateDeregisterID
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Return count of callbacks when
registering callbacks
* src/libxl/libxl_driver.c, src/libxl/libxl_driver.c,
src/qemu/qemu_driver.c, src/remote/remote_driver.c,
src/remote/remote_driver.c, src/uml/uml_driver.c,
src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Update
for change in APIs
The Xen & VBox drivers deal with callbacks & dispatching of
events directly. All the other drivers use a timer to dispatch
events from a clean stack state, rather than deep inside the
drivers. Convert Xen & VBox over to virDomainEventState so
that they match behaviour of other drivers
* src/conf/domain_event.c: Return count of remaining
callbacks when unregistering event callback
* src/vbox/vbox_tmpl.c, src/xen/xen_driver.c,
src/xen/xen_driver.h: Convert to virDomainEventState
Add the core functions that implement the functionality of the API.
Suspend is done by using an asynchronous mechanism so that we can return
the status to the caller before the host gets suspended. This asynchronous
operation is achieved by suspending the host in a separate thread of
execution. However, returning the status to the caller is only best-effort,
but not guaranteed.
To resume the host, an RTC alarm is set up (based on how long we want to
suspend) before suspending the host. When this alarm fires, the host
gets woken up.
Suspend-to-RAM operation on a host running Linux can take upto more than 20
seconds, depending on the load of the system. (Freezing of tasks, an operation
preceding any suspend operation, is given up after a 20 second timeout).
And Suspend-to-Disk can take even more time, considering the time required
for compaction, creating the memory image and writing it to disk etc.
So, we do not allow the user to specify a suspend duration of less than 60
seconds, to be on the safer side, since we don't want to prematurely declare
failure when we only had to wait for some more time.
While Xen only has a single paravirt console, UML, and
QEMU both support multiple paravirt consoles. The LXC
driver can also be trivially made to support multiple
consoles. This patch extends the XML to allow multiple
<console> elements in the XML. It also makes the UML
and QEMU drivers support this config.
* src/conf/domain_conf.c, src/conf/domain_conf.h: Allow
multiple <console> devices
* src/lxc/lxc_driver.c, src/xen/xen_driver.c,
src/xenxs/xen_sxpr.c, src/xenxs/xen_xm.c: Update for
internal API changes
* src/security/security_selinux.c, src/security/virt-aa-helper.c:
Only label consoles that aren't a copy of the serial device
* src/qemu/qemu_command.c, src/qemu/qemu_driver.c,
src/qemu/qemu_process.c, src/uml/uml_conf.c,
src/uml/uml_driver.c: Support multiple console devices
* tests/qemuxml2xmltest.c, tests/qemuxml2argvtest.c: Extra
tests for multiple virtio consoles. Set QEMU_CAPS_CHARDEV
for all console /channel tests
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-auto.args,
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
tests/qemuxml2argvdata/qemuxml2argv-console-virtio.args: Update
for correct chardev syntax
* tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.args,
tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.xml: New
test file
This adds support for a libvirt client configuration file
either /etc/libvirt/libvirt.conf for privileged clients,
or $HOME/.libvirt/libvirt.conf for unprivileged clients.
It allows one parameter
uri_aliases = [
"hail=qemu+ssh://root@hail.cloud.example.com/system",
"sleet=qemu+ssh://root@sleet.cloud.example.com/system",
]
Any call to virConnectOpen with a non-NULL URI will first
attempt to match against the uri_aliases list. An application
can disable this by using VIR_CONNECT_NO_ALIASES
* docs/uri.html.in: Document URI aliases
* include/libvirt/libvirt.h.in: Add VIR_CONNECT_NO_ALIASES
* libvirt.spec.in, mingw32-libvirt.spec.in: Add /etc/libvirt/libvirt.conf
* src/Makefile.am: Install default config file
* src/libvirt.c: Add support for URI aliases
* src/remote/remote_driver.c: Don't try to handle URIs
with no scheme and which clearly are not paths
* src/util/conf.c: Don't raise error on virConfFree(NULL)
* src/xen/xen_driver.c: Don't raise error on URIs
with no scheme
virInitialize() → xenRegister() → xenhypervisorInit() determines the
version of the Hypervisor. This breaks xencapstest when building as root
on a dom0 system, since xenHypervisorBuildCapabilities() adds the "hap"
and "viridian" features based on the detected version.
Add an optional parameter to xenhypervisorInit() to disable automatic
detection of the Hypervisor version. The passed in arguments are used
instead.
Signed-off-by: Philipp Hahn <hahn@univention.de>
Revert 6a1f5f568f. Now that libvirt_iohelper takes fds by
inheritance rather than by open() (commit 1eb66479), there is
no longer a race where the parent can unlink() a file prior to
the iohelper open()ing the same file. From there, it makes
more sense to have the callers both create and unlink, rather
than the caller create and the stream unlink, since the latter
was only needed when iohelper had to do the unlink.
* src/fdstream.h (virFDStreamOpenFile, virFDStreamCreateFile):
Callers are responsible for deletion.
* src/fdstream.c (virFDStreamOpenFileInternal): Don't leak created
file on failure.
(virFDStreamOpenFile, virFDStreamCreateFile): Drop parameter.
* src/lxc/lxc_driver.c (lxcDomainOpenConsole): Update callers.
* src/qemu/qemu_driver.c (qemuDomainScreenshot)
(qemuDomainOpenConsole): Likewise.
* src/storage/storage_driver.c (storageVolumeDownload)
(storageVolumeUpload): Likewise.
* src/uml/uml_driver.c (umlDomainOpenConsole): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainScreenshot): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainOpenConsole): Likewise.
No need to use a for loop if we know there is exactly one client.
Found by:
for f in $(sed -n 's/.*Drv[^ ]* \([^;]*\);.*/\1/p' src/xen/xen_driver.h)
do
git grep "\(\.\|->\)$f\b" src/xen
done | cat
and looking through the resulting list to see which callback struct
members are used exactly once. The next patch will ensure that we
don't reintroduce uses of these callbacks.
* src/xen/xen_driver.c (xenUnifiedClose): Call close
unconditionally, to match xenUnifiedOpen.
(xenUnifiedNodeGetInfo, xenUnifiedDomainCreateXML)
(xenUnifiedDomainSave, xenUnifiedDomainRestore)
(xenUnifiedDomainCoreDump, xenUnifiedDomainUpdateDeviceFlags):
Make direct call to lone implementation.
* src/xen/xend_internal.h (xenDaemonDomainCoreDump)
(xenDaemonUpdateDeviceFlags, xenDaemonCreateXML): Add prototypes.
* src/xen/xend_internal.c (xenDaemonDomainCoreDump)
(xenDaemonUpdateDeviceFlags, xenDaemonCreateXML): Export.
The callback struct is great when iterating through several
possibilities, but when calling a known callback, it's just
overhead. We can make the direct call in those cases.
* src/xen/xen_driver.c (xenUnifiedOpen, xenUnifiedDomainSuspend)
(xenUnifiedDomainResume, xenUnifiedDomainDestroyFlags): Make
direct calls instead of going through callback.
Using C99 initializers and xen-specific prefixes will make it
so that future patches are less likely to add callback members
to the xenUnifiedDriver struct, since the goal is to get rid
of the callback struct in the first place.
* src/xen/xen_driver.h (xenUnifiedDriver): Rename all struct
members, to make it obvious which ones are still in use.
* src/xen/xen_driver.c: Update all callers.
* src/xen/xen_hypervisor.c (xenHypervisorDriver): Rewrite with C99
initializers.
* src/xen/xend_internal.c (xenDaemonDriver): Likewise.
* src/xen/xs_internal.c (xenStoreDriver): Likewise.
* src/xen/xm_internal.c (xenXMDriver): Likewise.
* src/xen/xen_inotify.c (xenInotifyDriver): Likewise.
Now that virDomainSetVcpusFlags knows about VIR_DOMAIN_AFFECT_CURRENT,
so should virDomainGetVcpusFlags.
Unfortunately, the virsh counterpart 'virsh vcpucount' has already
commandeered --current for a different meaning, so teaching virsh
to expose this in the next patch will require a bit of care.
* src/libvirt.c (virDomainGetVcpusFlags): Allow
VIR_DOMAIN_AFFECT_CURRENT.
* src/libxl/libxl_driver.c (libxlDomainGetVcpusFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetVcpusFlags): Likewise.
* src/test/test_driver.c (testDomainGetVcpusFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetVcpusFlags): Likewise.
For all hypervisors that support save and restore, the new API
now performs the same functions as the old.
VBox is excluded from this list, because its existing domainsave
is broken (there is no corresponding domainrestore, and there
is no control over the filename used in the save). A later
patch should change vbox to use its implementation for
managedsave, and teach start to use managedsave results.
* src/libxl/libxl_driver.c (libxlDomainSave): Move guts...
(libxlDomainSaveFlags): ...to new function.
(libxlDomainRestore): Move guts...
(libxlDomainRestoreFlags): ...to new function.
* src/test/test_driver.c (testDomainSave, testDomainSaveFlags)
(testDomainRestore, testDomainRestoreFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainSave)
(xenUnifiedDomainSaveFlags, xenUnifiedDomainRestore)
(xenUnifiedDomainRestoreFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainSave, qemudDomainRestore):
Rename and move guts.
(qemuDomainSave, qemuDomainSaveFlags, qemuDomainRestore)
(qemuDomainRestoreFlags): ...here.
(qemudDomainSaveFlag): Rename...
(qemuDomainSaveInternal): ...to this, and update callers.
Build failure on xenapi_driver from compiler warnings (flags was unused).
Build failure on xen (incorrect number of arguments). And in fixing
that, I obeyed the comments of struct xenUnifiedDriver that state
that we want to minimize the number of callback functions in that
struct, not add to it.
* src/xen/xen_driver.c (xenUnifiedDomainDestroyFlags): Use correct
arguments.
(xenUnifiedDomainDestroy): Simplify.
* src/xen/xen_driver.h (xenUnifiedDriver): Remove unused callback.
* src/xen/xen_hypervisor.c (xenHypervisorDestroyDomain): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainDestroy): Likewise.
* src/xen/xend_internal.h (xenDaemonDomainDestroyFlags): Likewise.
* src/xen/xm_internal.c (xenXMDriver): Likewise.
* src/xen/xs_internal.c (xenStoreDriver): Likewise.
* src/xen/xen_inotify.c (xenInotifyDriver): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainDestroyFlags): Reject
unknown flags.
The drivers were accepting domain configs without checking if those
were actually meant for them. For example the LXC driver happily
accepts configs with type QEMU.
Add a check for the expected domain types to the virDomainDefParse*
functions.
Well, the remaining drivers that already had the get/set
scheduler parameter functionality to begin with.
For now, this blindly treats VIR_DOMAIN_SCHEDINFO_CURRENT as
the only supported operation for these 5 domains; it will
take domain-specific patches if more specific behavior is
preferred.
* src/esx/esx_driver.c (esxDomainGetSchedulerParameters)
(esxDomainSetSchedulerParameters): Move guts...
(esxDomainGetSchedulerParametersFlags)
(esxDomainSetSchedulerParametersFlags): ...to new functions.
* src/libxl/libxl_driver.c (libxlDomainGetSchedulerParameters)
(libxlDomainSetSchedulerParameters)
(libxlDomainGetSchedulerParametersFlags)
(libxlDomainSetSchedulerParametersFlags): Likewise.
* src/lxc/lxc_driver.c (lxcGetSchedulerParameters)
(lxcSetSchedulerParameters, lxcGetSchedulerParametersFlags)
(lxcSetSchedulerParametersFlags): Likewise.
* src/test/test_driver.c (testDomainGetSchedulerParams)
(testDomainSetSchedulerParams, testDomainGetSchedulerParamsFlags)
(testDomainSetSchedulerParamsFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetSchedulerParameters)
(xenUnifiedDomainSetSchedulerParameters)
(xenUnifiedDomainGetSchedulerParametersFlags)
(xenUnifiedDomainSetSchedulerParametersFlags): Likewise.
Change all the driver struct initializers to use the
C99 style, leaving out unused fields. This will make
it possible to add new APIs without changing every
driver. eg change:
qemudDomainResume, /* domainResume */
qemudDomainShutdown, /* domainShutdown */
NULL, /* domainReboot */
qemudDomainDestroy, /* domainDestroy */
to
.domainResume = qemudDomainResume,
.domainShutdown = qemudDomainShutdown,
.domainDestroy = qemudDomainDestroy,
And get rid of any existing C99 style initializersr which
set NULL, eg change
.listPools = vboxStorageListPools,
.numOfDefinedPools = NULL,
.listDefinedPools = NULL,
.findPoolSources = NULL,
.poolLookupByName = vboxStoragePoolLookupByName,
to
.listPools = vboxStorageListPools,
.poolLookupByName = vboxStoragePoolLookupByName,
Fix some driver names:
s/virDrvCPUCompare/virDrvCompareCPU/
s/virDrvCPUBaseline/virDrvBaselineCPU/
s/virDrvQemuDomainMonitorCommand/virDrvDomainQemuMonitorCommand/
s/virDrvSecretNumOfSecrets/virDrvNumOfSecrets/
s/virDrvSecretListSecrets/virDrvListSecrets/
And some driver struct field names:
s/getFreeMemory/nodeGetFreeMemory/
This is needed if we want to transfer a temporary file. If the
transfer is done with iohelper, we might run into a race condition,
where we unlink() file before iohelper is executed.
* src/fdstream.c, src/fdstream.h,
src/util/iohelper.c: Add new option
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
src/storage/storage_driver.c, src/uml/uml_driver.c,
src/xen/xen_driver.c: Expand existing function calls
These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
This matches the public API and helps to get rid of some special
case code in the remote generator.
Rename driver API functions and XDR protocol structs.
No functional change included outside of the remote generator.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=664059
Reattaching pci device back to host without destroying guest or
detaching device from guest would cause host to crash. This patch adds
a check before doing device reattach. If the device is being assigned
to guest, libvirt refuses to reattach device to host. The patch only
works for Xen, for it just checks xenstore to get pci device
information.
Signed-off-by: Yufang Zhang <yuzhang@redhat.com>
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
