The linux kernel recently added support for paravirtual spinlock
handling to avoid performance regressions on overcomitted hosts. This
feature needs to be turned in the hypervisor so that the guest OS is
notified about the possible support.

This patch adds a new feature "paravirt-spinlock" to the XML and
supporting code to enable the "kvm_pv_unhalt" pseudo CPU feature in
qemu.

https://bugzilla.redhat.com/show_bug.cgi?id=1008989

Currently we were storing domain feature flags in a bit field as the
they were either enabled or disabled. New features such as paravirtual
spinlocks however can be tri-state as the default option may depend on
hypervisor version.

To allow storing tri-state feature state in the same place instead of
having to declare dedicated variables for each feature this patch
refactors the bit field to an array.

Some of the emulator features are presented in the <features> element in
the domain XML although they are virtual CPUID feature bits when
presented to the guest. To avoid confusing the users with these
features, as they are not configurable via the <cpu> element, this patch
adds an internal array where those can be stored privately instead of
exposing them in the XML.

Additionaly KVM feature bits are added as example usage of this code.

The qemu monitor supports retrieval of actual CPUID bits presented to
the guest using QMP monitor. Add APIs to extract these information and
tests for them.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

The CPUID functions were stored in multiple arrays according to a
specified prefix of those. This made it very hard to add another prefix
to store KVM CPUID features (0x40000000). Instead of hardcoding a third
array this patch changes the approach used:

The code is refactored to use a single array where the CPUID functions
are stored ordered by the cpuid function so that they don't depend on
the specific prefix and don't waste memory. The code is also less
complex using this approach. A trateoff to this is the change from O(N)
complexity to O(N^2) in x86DataAdd and x86DataSubtract. The rest of the
functions were already using O(N^2) algorithms.

vol-clone reports out of memory error with disk type on ppc64.

Currently, wbytes is defined as size_t type (8 bytes), but
args's value in ioctl(fd, args..) in kernel is int (4 bytes).
This makes wbytes 2^32 times larger, causing an out of memory error.

This patch changes size_t to int to synchronize with kernel.

[1] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/block/ioctl.c?id=5e01dc7b#n363
[2] https://lkml.org/lkml/2013/11/1/620Signed-off-by: NLi Zhang <zhlcindy@linux.vnet.ibm.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

Since 86d90b3a (yes, my patch; again) we are supporting NBD storage
migration. However, on error recovery path we got the steps reversed.
The correct order is: return NBD port to the virPortAllocator and then
either unlock the vm or remove it from the driver. Not vice versa.

==11192== Invalid write of size 4
==11192==    at 0x11488559: qemuMigrationPrepareAny (qemu_migration.c:2459)
==11192==    by 0x11488EA6: qemuMigrationPrepareDirect (qemu_migration.c:2652)
==11192==    by 0x114D1509: qemuDomainMigratePrepare3Params (qemu_driver.c:10332)
==11192==    by 0x519075D: virDomainMigratePrepare3Params (libvirt.c:7290)
==11192==    by 0x1502DA: remoteDispatchDomainMigratePrepare3Params (remote.c:4798)
==11192==    by 0x12DECA: remoteDispatchDomainMigratePrepare3ParamsHelper (remote_dispatch.h:5741)
==11192==    by 0x5212127: virNetServerProgramDispatchCall (virnetserverprogram.c:435)
==11192==    by 0x5211C86: virNetServerProgramDispatch (virnetserverprogram.c:305)
==11192==    by 0x520A8FD: virNetServerProcessMsg (virnetserver.c:165)
==11192==    by 0x520A9E1: virNetServerHandleJob (virnetserver.c:186)
==11192==    by 0x50DA78F: virThreadPoolWorker (virthreadpool.c:144)
==11192==    by 0x50DA11C: virThreadHelper (virthreadpthread.c:161)
==11192==  Address 0x1368baa0 is 576 bytes inside a block of size 688 free'd
==11192==    at 0x4A07F5C: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==11192==    by 0x5079A2F: virFree (viralloc.c:580)
==11192==    by 0x11456C34: qemuDomainObjPrivateFree (qemu_domain.c:267)
==11192==    by 0x50F41B4: virDomainObjDispose (domain_conf.c:2034)
==11192==    by 0x50C2991: virObjectUnref (virobject.c:262)
==11192==    by 0x50F4CFC: virDomainObjListRemove (domain_conf.c:2361)
==11192==    by 0x1145C125: qemuDomainRemoveInactive (qemu_domain.c:2087)
==11192==    by 0x11488520: qemuMigrationPrepareAny (qemu_migration.c:2456)
==11192==    by 0x11488EA6: qemuMigrationPrepareDirect (qemu_migration.c:2652)
==11192==    by 0x114D1509: qemuDomainMigratePrepare3Params (qemu_driver.c:10332)
==11192==    by 0x519075D: virDomainMigratePrepare3Params (libvirt.c:7290)
==11192==    by 0x1502DA: remoteDispatchDomainMigratePrepare3Params (remote.c:4798)
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

One of my previous patches (c7ac2519) did try to fix the issue when
domain dies too soon during migration. However, this clumsy approach was
missing removal of qemuProcessHandleMonitorDestroy resulting in double
unrefing of mon->vm and hence producing the daemon crash:

==11843== Invalid read of size 4
==11843==    at 0x50C28C5: virObjectUnref (virobject.c:255)
==11843==    by 0x1148F7DB: qemuMonitorDispose (qemu_monitor.c:258)
==11843==    by 0x50C2991: virObjectUnref (virobject.c:262)
==11843==    by 0x50C2D13: virObjectFreeCallback (virobject.c:388)
==11843==    by 0x509C37B: virEventPollCleanupHandles (vireventpoll.c:583)
==11843==    by 0x509C711: virEventPollRunOnce (vireventpoll.c:652)
==11843==    by 0x509A620: virEventRunDefaultImpl (virevent.c:274)
==11843==    by 0x520D21C: virNetServerRun (virnetserver.c:1112)
==11843==    by 0x11F368: main (libvirtd.c:1513)
==11843==  Address 0x13b88864 is 4 bytes inside a block of size 136 free'd
==11843==    at 0x4A07F5C: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==11843==    by 0x5079A2F: virFree (viralloc.c:580)
==11843==    by 0x50C29E3: virObjectUnref (virobject.c:270)
==11843==    by 0x114770E4: qemuProcessHandleMonitorDestroy (qemu_process.c:1103)
==11843==    by 0x1148F7CB: qemuMonitorDispose (qemu_monitor.c:257)
==11843==    by 0x50C2991: virObjectUnref (virobject.c:262)
==11843==    by 0x50C2D13: virObjectFreeCallback (virobject.c:388)
==11843==    by 0x509C37B: virEventPollCleanupHandles (vireventpoll.c:583)
==11843==    by 0x509C711: virEventPollRunOnce (vireventpoll.c:652)
==11843==    by 0x509A620: virEventRunDefaultImpl (virevent.c:274)
==11843==    by 0x520D21C: virNetServerRun (virnetserver.c:1112)
==11843==    by 0x11F368: main (libvirtd.c:1513)
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Use absDirPath instead of absFilePath.

https://bugzilla.redhat.com/show_bug.cgi?id=1028107

So far we are checking if qemu supports 'nbd-server-start'. This,
however, makes no sense on the source as nbd-server-* is used on the
destination. On the source the 'drive-mirror' is used instead.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

A copy-paste error.
s/model/vendor id
Signed-off-by: NChen Hanxiao <chenhanxiao@cn.fujitsu.com>

Since 21685c95 we have tests/virpcitestdata dir containing the PCI
config files for some dummy PCI devices that are used int virpcitest.
However, the directory containing the config files is not distributed
making 'make rpm' fail.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

For some strange reason virDomainDiskSourcePoolDefParse accessed def of
the disk and allocated the pool object in it. To avoid the need to carry
over the disk definition object, refactor this function to return the
allocated object instead.

Commit b0f85462 broke the build on mingw, by exposing code that
had Linux-specific dependencies but which was previously protected
by libnuma ifdef guards:

make[3]: Entering directory `/home/eblake/libvirt-tmp/build/src'
  CC       libvirt_driver_la-nodeinfo.lo
../../src/nodeinfo.c: In function 'virNodeGetSiblingsList':
../../src/nodeinfo.c:1543:30: error: 'SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX' undeclared (first use in this function)
     if (virFileReadAll(path, SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX, &buf) < 0)
                              ^
../../src/nodeinfo.c:1543:30: note: each undeclared identifier is reported only once for each function it appears in
../../src/nodeinfo.c: In function 'virNodeCapsFillCPUInfo':
../../src/nodeinfo.c:1562:5: error: implicit declaration of function 'virNodeGetCpuValue' [-Werror=implicit-function-declaration]
     if ((tmp = virNodeGetCpuValue(SYSFS_CPU_PATH, cpu_id,
     ^
../../src/nodeinfo.c:1562:5: error: nested extern declaration of 'virNodeGetCpuValue' [-Werror=nested-externs]
../../src/nodeinfo.c:1562:35: error: 'SYSFS_CPU_PATH' undeclared (first use in this function)
     if ((tmp = virNodeGetCpuValue(SYSFS_CPU_PATH, cpu_id,
                                   ^
cc1: all warnings being treated as errors

* src/nodeinfo.c (virNodeCapsFillCPUInfo): Make conditional.
(virNodeGetSiblingsList): Move into #ifdef linux block.
Signed-off-by: NEric Blake <eblake@redhat.com>

This gets rid of another stat() per volume, as well as cutting
bytes read in half, when populating the volumes of a directory
pool during a pool refresh.  Not to mention that it provides an
interface that can let gluster pools also probe file types.

* src/util/virstoragefile.h (virStorageFileProbeFormatFromFD):
Delete.
(virStorageFileProbeFormatFromBuf): New prototype.
(VIR_STORAGE_MAX_HEADER): New constant, based on...
* src/util/virstoragefile.c (STORAGE_MAX_HEAD): ...old name.
(vmdk4GetBackingStore, virStorageFileGetMetadataInternal)
(virStorageFileProbeFormat): Adjust clients.
(virStorageFileProbeFormatFromFD): Delete.
(virStorageFileProbeFormatFromBuf): Export.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget):
Adjust client.
* src/libvirt_private.syms (virstoragefile.h): Adjust exports.
Signed-off-by: NEric Blake <eblake@redhat.com>

Future patches will want to learn metadata about a file using
a buffer that was already parsed in order to probe the file's
format.  Rather than reopening and re-reading the file, it makes
sense to separate getting file contents from actually parsing
those contents.

* src/util/virstoragefile.c (virStorageFileGetMetadataFromBuf)
(virStorageFileGetMetadataFromFDInternal): New functions.
(virStorageFileGetMetadataInternal): Hoist fstat() and read() into
callers.
(virStorageFileGetMetadataFromFD)
(virStorageFileGetMetadataRecurse): Rework clients.
* src/util/virstoragefile.h (virStorageFileGetMetadataFromBuf):
New prototype.
* src/libvirt_private.syms (virstoragefile.h): Export it.
Signed-off-by: NEric Blake <eblake@redhat.com>

We are calling fstat() at least twice per storage volume in
a directory storage pool; this is rather wasteful.  Refactoring
this is also a step towards making code reusable for gluster,
where gluster can provide struct stat but cannot use fstat().

* src/storage/storage_backend.h
(virStorageBackendVolOpenCheckMode)
(virStorageBackendUpdateVolTargetInfoFD): Update signature.
* src/storage/storage_backend.c
(virStorageBackendVolOpenCheckMode): Pass stat results back.
(virStorageBackendUpdateVolTargetInfoFD): Use existing stats.
(virStorageBackendVolOpen, virStorageBackendUpdateVolTargetInfo):
Update callers.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget):
Likewise.
* src/storage/storage_backend_scsi.c
(virStorageBackendSCSIUpdateVolTargetInfo): Likewise.
* src/storage/storage_backend_mpath.c
(virStorageBackendMpathUpdateVolTargetInfo): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Our backing file chain code was not very robust to an ill-timed
EINTR, which could lead to a short read causing us to randomly
treat metadata differently than usual.  But the existing
virFileReadLimFD forces an error if we don't read the entire
file, even though we only care about the header of the file.
So add a new virFile function that does what we want.

* src/util/virfile.h (virFileReadHeaderFD): New prototype.
* src/util/virfile.c (virFileReadHeaderFD): New function.
* src/libvirt_private.syms (virfile.h): Export it.
* src/util/virstoragefile.c (virStorageFileGetMetadataInternal)
(virStorageFileProbeFormatFromFD): Use it.
Signed-off-by: NEric Blake <eblake@redhat.com>

'unsigned char *' makes sense if you are doing math on bytes and
don't want to worry about wraparound from a signed 'char'; but
since all we are doing is memcmp() or virReadBufInt*[LB]E(), which
are both safe on either type of char, and since read() prefers to
operate on 'char *', it's simpler to avoid casts by just typing
things as 'char *' from the get-go.  [Technically, read can
operate on an 'unsigned char *' thanks to the C rule that any
pointer can be implicitly converted to 'char *' for legacy K&R
compatibility; but where this patch saves us is if we try to use
virfile.h functions that take 'char **' in order to allocate the
buffer, where the compiler would barf on type mismatch.]

* src/util/virstoragefile.c (FileTypeInfo): Avoid unsigned char.
(cowGetBackingStore, qcow2GetBackingStoreFormat)
(qcowXGetBackingStore, qcow1GetBackingStore)
(qcow2GetBackingStore, vmdk4GetBackingStore, qedGetBackingStore)
(virStorageFileMatchesMagic, virStorageFileMatchesVersion)
(virStorageFileProbeFormatFromBuf, qcow2GetFeatures)
(virStorageFileGetMetadataInternal)
(virStorageFileProbeFormatFromFD): Simplify clients.
Signed-off-by: NEric Blake <eblake@redhat.com>

Starting from v2.4 (released today!), SystemTap can use libvirt to
execute scripts inside virtual machines.
Signed-off-by: NEric Blake <eblake@redhat.com>

It uses the same functionalities of the qemu driver.
Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>

Since the 90139a62 commit the error is copied into mon->lastError but
it's never freed from there.

==31989== 395 bytes in 1 blocks are definitely lost in loss record 877 of 978
==31989==    at 0x4A06C2B: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==31989==    by 0x7EAF129: strdup (in /lib64/libc-2.15.so)
==31989==    by 0x50D586C: virStrdup (virstring.c:554)
==31989==    by 0x50976C1: virCopyError (virerror.c:191)
==31989==    by 0x5097A35: virCopyLastError (virerror.c:312)
==31989==    by 0x114909A9: qemuMonitorIO (qemu_monitor.c:690)
==31989==    by 0x509BEDE: virEventPollDispatchHandles (vireventpoll.c:501)
==31989==    by 0x509C701: virEventPollRunOnce (vireventpoll.c:648)
==31989==    by 0x509A620: virEventRunDefaultImpl (virevent.c:274)
==31989==    by 0x520D21C: virNetServerRun (virnetserver.c:1112)
==31989==    by 0x11F368: main (libvirtd.c:1513)
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

s/fragement/fragment
Signed-off-by: NChen Hanxiao <chenhanxiao@cn.fujitsu.com>

If there's a migration cancelled, the bitmap of migration port should be
cleaned up too.
Signed-off-by: NZeng Junliang <zengjunliang@huawei.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1020135

If networkAllocateActualDevice() had failed due to a pool of hostdev
or direct devices being depleted, the calling function could still
call networkReleaseActualDevice() as part of its cleanup, and that
function would then unconditionally decrement the connections count
for the network, even though it hadn't been incremented (due to
failure of allocate). This *was* necessary because the .actual member
of the netdef was allocated with a "lazy" algorithm, only being
created if there was a need to store data there (e.g. if a device was
allocated from a pool, or bandwidth was allocated for the device), so
there was no simple way for networkReleaseActualDevice() to tell if
something really had been allocated (i.e. if "connections++" had been
executed).

This patch changes networkAllocateDevice() to *always* allocate an
actual device for any netdef of type='network', even if it isn't
needed for any other reason. This has no ill effects anywhere else in
the code (except for using a small amount of memory), and
networkReleaseActualDevice() can then determine if there was a
previous successful allocate by checking for .actual != NULL (if not,
it skips the "connections--").

This addition, however, requires some refactoring to be done.  First of
all, to match the best practice we should detach the device prior
resetting it. That's why testVirPCIDeviceDetach is detaching all devices
within 0000:00:01.0 and 0000:00:03.0 range. Then, the brand new test
will reset the 0000:00:02.0 device, so the last testVirPCIDeviceReattach
can reattach all the devices back.

In order to perform a PCI device reset, the dummy config file is not
sufficient anymore and must be replaced with real PCI config (binary
mess). Such config files are to be stored under tests/virpcitestdata/
and ought to have '.config' suffix.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Needed for architectures that don't use gcc atomic ops but pthread. This
fixes the armel build that otherwise breaks like:

 CCLD     virt-login-shell
 ../src/.libs/libvirt-setuid-rpc-client.a(libvirt_setuid_rpc_client_la-virobject.o): In function `virClassNew':
 /«PKGBUILDDIR»/debian/build/src/../../../src/util/virobject.c:150: undefined reference to `virAtomicLock'
 ../src/.libs/libvirt-setuid-rpc-client.a(libvirt_setuid_rpc_client_la-virobject.o): In function `virObjectNew':
 /«PKGBUILDDIR»/debian/build/src/../../../src/util/virobject.c:202: undefined reference to `virAtomicLock'
 ../src/.libs/libvirt-setuid-rpc-client.a(libvirt_setuid_rpc_client_la-virobject.o): In function `virObjectUnref':
 /«PKGBUILDDIR»/debian/build/src/../../../src/util/virobject.c:274: undefined reference to `virAtomicLock'
 ../src/.libs/libvirt-setuid-rpc-client.a(libvirt_setuid_rpc_client_la-virobject.o): In function `virObjectRef':
 /«PKGBUILDDIR»/debian/build/src/../../../src/util/virobject.c:295: undefined reference to `virAtomicLock'
 collect2: error: ld returned 1 exit status

See https://buildd.debian.org/status/fetch.php?pkg=libvirt&arch=armel&ver=1.1.4-1&stamp=1383588268

In the pci_driver_new function it is possible to set a list of
<vendor:device> IDs that the driver knows. These IDs are passed as
variable arguments and are processed  the usual way using va_start() and
va_arg(). However, after all arguments has been processed, we should
call va_end() what we aren't currently doing.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

A qcow2 file with a backing file of 'gluster://host/vol/file' should
not try to look for a directory named './gluster:/' in the file system.

* src/util/virstoragefile.c (virBackingStoreIsFile): Broaden check
to include all protocols.
Signed-off-by: NEric Blake <eblake@redhat.com>

Since qemu-kvm 1.1 [1] (since 1.3. in upstream QEMU [2])
'-no-kvm-pit-reinjection' has been deprecated.
Use -global kvm-pit.lost_tick_policy=discard instead.

https://bugzilla.redhat.com/show_bug.cgi?id=978719

[1] http://git.kernel.org/cgit/virt/kvm/qemu-kvm.git/commit/?id=4e4fa39
[2] http://git.qemu.org/?p=qemu.git;a=commitdiff;h=c21fb4f

Coverity complains that the call to virPCIDeviceDetach() in
qemuPrepareHostdevPCIDevices() doesn't check status return like
other calls.  Seems this just was lurking until a recent change
to this module resulted in Coverity looking harder and finding
the issue.  Introduced by 'a4efb2e3' when function was called
'pciReAttachDevice()'

Just added a ignore_value() since it doesn't appear to matter
if the call fails since we're on a failure path already.

Currently the LXC container tries to skip selinux/securityfs
mounts if the directory does not exist in the filesystem,
or if SELinux is disabled.

The former check is flawed because the /sys/fs/selinux
or /sys/kernel/securityfs directories may exist in sysfs
even if the mount type is disabled. Instead of just doing
an access() check, use an virFileIsMounted() to see if
the FS is actually present in the host OS. This also
avoids the need to check is_selinux_enabled().
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Some mounts must be skipped if running inside a user namespace,
since the kernel forbids their use. Instead of strcmp'ing the
filesystem type in the body of the loop, set an explicit flag
in the lxcBasicMounts table.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Currently the lxcBasicMounts array has separate entries for
most mounts, to reflect that we must do a separate mount
operation to make mounts read-only. Remove the duplicate
entries and instead set the MS_RDONLY flag against the main
entry. Then change lxcContainerMountBasicFS to look for the
MS_RDONLY flag, mask it out & do a separate bind mount.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The 'srcpath' variable is initialized from 'mnt->src' and never
changed thereafter. Some places continue to use 'mnt->src' and
others use 'srcpath'. Remove the pointless 'srcpath' variable
and use 'mnt->src' everywhere.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virLXCBasicMountInfo struct contains a 'char *opts'
field passed onto the mount() syscall. Every entry in the
list sets this to NULL though, so it can be removed to
simplify life.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add a function for efficiently checking if a path is a filesystem
mount point.

NB will not work for bind mounts, only true filesystem mounts.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This just introduces the test for bug fixed in df4283a5.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1018897

If a PCI deivce is not binded to any driver (e.g. there's yet no PCI
driver in the linux kernel) but still users want to passthru the device
we fail the whole operation as we fail to resolve the 'driver' link
under the PCI device sysfs tree. Obviously, this is not a fatal error
and it shouldn't be error at all.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>