/**
* virDomainLxcEnterCGroup:
* @domain: a domain object
* @flags: currently unused, pass 0
*
* This API is LXC specific, so it will only work with hypervisor
* connections to the LXC driver.
*
* Attaches the process to the control cgroups associated
* with the container @domain.
*
* Returns 0 on success, -1 on error
*/
int virDomainLxcEnterCGroup(virDomainPtr domain,
unsigned int flags)
{
virConnectPtr conn;
virCgroupPtr cgroup = NULL;
VIR_DOMAIN_DEBUG(domain, "flags=%x", flags);
virResetLastError();
virCheckDomainReturn(domain, -1);
conn = domain->conn;
virCheckReadOnlyGoto(conn->flags, error);
virCheckFlagsGoto(0, error);
if (virCgroupNewDetect(domain->id, -1, &cgroup) < 0)
goto error;
if (virCgroupAddTask(cgroup, getpid()) < 0)
goto error;
virCgroupFree(&cgroup);
return 0;
error:
virDispatchError(NULL);
virCgroupFree(&cgroup);
return -1;
}
/**
* virDomainLxcOpenNamespace:
* @domain: a domain object
* @fdlist: pointer to an array to be filled with FDs
* @flags: currently unused, pass 0
*
* This API is LXC specific, so it will only work with hypervisor
* connections to the LXC driver.
*
* Open the namespaces associated with the container @domain.
* The @fdlist array will be allocated to a suitable size,
* and filled with file descriptors for the namespaces. It
* is the caller's responsibility to close the file descriptors
*
* The returned file descriptors are intended to be used with
* the setns() system call.
*
* Returns the number of opened file descriptors, or -1 on error
*/
int
virDomainLxcOpenNamespace(virDomainPtr domain,
int **fdlist,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "fdlist=%p flags=%x", fdlist, flags);
virResetLastError();
virCheckDomainReturn(domain, -1);
conn = domain->conn;
virCheckNonNullArgGoto(fdlist, error);
virCheckReadOnlyGoto(conn->flags, error);
if (conn->driver->domainLxcOpenNamespace) {
int ret;
ret = conn->driver->domainLxcOpenNamespace(domain,
fdlist,
flags);
if (ret < 0)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return -1;
}
/**
* virDomainSnapshotCurrent:
* @domain: a domain object
* @flags: extra flags; not used yet, so callers should always pass 0
*
* Get the current snapshot for a domain, if any.
*
* virDomainSnapshotFree should be used to free the resources after the
* snapshot object is no longer needed.
*
* Returns a domain snapshot object or NULL in case of failure. If the
* current domain snapshot cannot be found, then the VIR_ERR_NO_DOMAIN_SNAPSHOT
* error is raised.
*/
virDomainSnapshotPtr
virDomainSnapshotCurrent(virDomainPtr domain,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "flags=0x%x", flags);
virResetLastError();
virCheckDomainReturn(domain, NULL);
conn = domain->conn;
if (conn->driver->domainSnapshotCurrent) {
virDomainSnapshotPtr snap;
snap = conn->driver->domainSnapshotCurrent(domain, flags);
if (!snap)
goto error;
return snap;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return NULL;
}
/**
* virDomainSnapshotLookupByName:
* @domain: a domain object
* @name: name for the domain snapshot
* @flags: extra flags; not used yet, so callers should always pass 0
*
* Try to lookup a domain snapshot based on its name.
*
* Returns a domain snapshot object or NULL in case of failure. If the
* domain snapshot cannot be found, then the VIR_ERR_NO_DOMAIN_SNAPSHOT
* error is raised.
*/
virDomainSnapshotPtr
virDomainSnapshotLookupByName(virDomainPtr domain,
const char *name,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "name=%s, flags=0x%x", name, flags);
virResetLastError();
virCheckDomainReturn(domain, NULL);
conn = domain->conn;
virCheckNonNullArgGoto(name, error);
if (conn->driver->domainSnapshotLookupByName) {
virDomainSnapshotPtr dom;
dom = conn->driver->domainSnapshotLookupByName(domain, name, flags);
if (!dom)
goto error;
return dom;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return NULL;
}
/**
* virDomainListAllSnapshots:
* @domain: a domain object
* @snaps: pointer to variable to store the array containing snapshot objects
* or NULL if the list is not required (just returns number of
* snapshots)
* @flags: bitwise-OR of supported virDomainSnapshotListFlags
*
* Collect the list of domain snapshots for the given domain and allocate
* an array to store those objects. This API solves the race inherent in
* virDomainSnapshotListNames().
*
* If @flags contains VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL and @snaps
* is non-NULL, and no other connection is modifying snapshots, then
* it is guaranteed that for any snapshot in the resulting list, no
* snapshots later in the list can be reached by a sequence of
* virDomainSnapshotGetParent() starting from that earlier snapshot;
* otherwise, the order of snapshots in the resulting list is
* unspecified.
*
* By default, this command covers all snapshots. It is also possible
* to limit things to just snapshots with no parents, when @flags
* includes VIR_DOMAIN_SNAPSHOT_LIST_ROOTS. Additional filters are
* provided in groups listed below. Within a group, bits are mutually
* exclusive, where all possible snapshots are described by exactly
* one bit from the group. Some hypervisors might reject particular
* flags where it cannot make a distinction for filtering. If the set
* of filter flags selected forms an impossible combination, the
* hypervisor may return either 0 or an error.
*
* The first group of @flags is VIR_DOMAIN_SNAPSHOT_LIST_LEAVES and
* VIR_DOMAIN_SNAPSHOT_LIST_NO_LEAVES, to filter based on snapshots that
* have no further children (a leaf snapshot).
*
* The next group of @flags is VIR_DOMAIN_SNAPSHOT_LIST_METADATA and
* VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA, for filtering snapshots based on
* whether they have metadata that would prevent the removal of the last
* reference to a domain.
*
* The next group of @flags is VIR_DOMAIN_SNAPSHOT_LIST_INACTIVE,
* VIR_DOMAIN_SNAPSHOT_LIST_ACTIVE, and VIR_DOMAIN_SNAPSHOT_LIST_DISK_ONLY,
* for filtering snapshots based on what domain state is tracked by the
* snapshot.
*
* The next group of @flags is VIR_DOMAIN_SNAPSHOT_LIST_INTERNAL and
* VIR_DOMAIN_SNAPSHOT_LIST_EXTERNAL, for filtering snapshots based on
* whether the snapshot is stored inside the disk images or as
* additional files.
*
* Returns the number of domain snapshots found or -1 and sets @snaps to
* NULL in case of error. On success, the array stored into @snaps is
* guaranteed to have an extra allocated element set to NULL but not included
* in the return count, to make iteration easier. The caller is responsible
* for calling virDomainSnapshotFree() on each array element, then calling
* free() on @snaps.
*/
int
virDomainListAllSnapshots(virDomainPtr domain, virDomainSnapshotPtr **snaps,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "snaps=%p, flags=0x%x", snaps, flags);
virResetLastError();
if (snaps)
*snaps = NULL;
virCheckDomainReturn(domain, -1);
conn = domain->conn;
if (conn->driver->domainListAllSnapshots) {
int ret = conn->driver->domainListAllSnapshots(domain, snaps, flags);
if (ret < 0)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return -1;
}
/**
* virDomainSnapshotListNames:
* @domain: a domain object
* @names: array to collect the list of names of snapshots
* @nameslen: size of @names
* @flags: bitwise-OR of supported virDomainSnapshotListFlags
*
* Collect the list of domain snapshots for the given domain, and store
* their names in @names. The value to use for @nameslen can be determined
* by virDomainSnapshotNum() with the same @flags.
*
* If @flags contains VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL, and no
* other connection is modifying snapshots, then it is guaranteed that
* for any snapshot in the resulting list, no snapshots later in the
* list can be reached by a sequence of virDomainSnapshotGetParent()
* starting from that earlier snapshot; otherwise, the order of
* snapshots in the resulting list is unspecified.
*
* By default, this command covers all snapshots. It is also possible
* to limit things to just snapshots with no parents, when @flags
* includes VIR_DOMAIN_SNAPSHOT_LIST_ROOTS. Additional filters are
* provided via the same @flags values as documented in
* virDomainListAllSnapshots().
*
* Note that this command is inherently racy: another connection can
* define a new snapshot between a call to virDomainSnapshotNum() and
* this call. You are only guaranteed that all currently defined
* snapshots were listed if the return is less than @nameslen. Likewise,
* you should be prepared for virDomainSnapshotLookupByName() to fail when
* converting a name from this call into a snapshot object, if another
* connection deletes the snapshot in the meantime. For more control over
* the results, see virDomainListAllSnapshots().
*
* Returns the number of domain snapshots found or -1 in case of error.
* The caller is responsible to call free() for each member of the array.
*/
int
virDomainSnapshotListNames(virDomainPtr domain, char **names, int nameslen,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "names=%p, nameslen=%d, flags=0x%x",
names, nameslen, flags);
virResetLastError();
virCheckDomainReturn(domain, -1);
conn = domain->conn;
virCheckNonNullArgGoto(names, error);
virCheckNonNegativeArgGoto(nameslen, error);
if (conn->driver->domainSnapshotListNames) {
int ret = conn->driver->domainSnapshotListNames(domain, names,
nameslen, flags);
if (ret < 0)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return -1;
}
/**
* virDomainQemuMonitorCommand:
* @domain: a domain object
* @cmd: the qemu monitor command string
* @result: a string returned by @cmd
* @flags: bitwise-or of supported virDomainQemuMonitorCommandFlags
*
* This API is QEMU specific, so it will only work with hypervisor
* connections to the QEMU driver.
*
* Send an arbitrary monitor command @cmd to @domain through the
* qemu monitor. There are several requirements to safely and
* successfully use this API:
*
* - A @cmd that queries state without making any modifications is safe
* - A @cmd that alters state that is also tracked by libvirt is unsafe,
* and may cause libvirtd to crash
* - A @cmd that alters state not tracked by the current version of
* libvirt is possible as a means to test new qemu features before
* they have support in libvirt, but no guarantees are made to safety
*
* If VIR_DOMAIN_QEMU_MONITOR_COMMAND_HMP is set, the command is
* considered to be a human monitor command and libvirt will automatically
* convert it into QMP if needed. In that case the @result will also
* be converted back from QMP.
*
* If successful, @result will be filled with the string output of the
* @cmd, and the caller must free this string.
*
* Returns 0 in case of success, -1 in case of failure
*
*/
int
virDomainQemuMonitorCommand(virDomainPtr domain, const char *cmd,
char **result, unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "cmd=%s, result=%p, flags=%x",
cmd, result, flags);
virResetLastError();
virCheckDomainReturn(domain, -1);
conn = domain->conn;
virCheckNonNullArgGoto(result, error);
virCheckReadOnlyGoto(conn->flags, error);
if (conn->driver->domainQemuMonitorCommand) {
int ret;
ret = conn->driver->domainQemuMonitorCommand(domain, cmd, result,
flags);
if (ret < 0)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return -1;
}
/**
* virDomainQemuAgentCommand:
* @domain: a domain object
* @cmd: the guest agent command string
* @timeout: timeout seconds
* @flags: execution flags
*
* Execute an arbitrary Guest Agent command.
*
* Issue @cmd to the guest agent running in @domain.
* @timeout must be -2, -1, 0 or positive.
* VIR_DOMAIN_QEMU_AGENT_COMMAND_BLOCK(-2): meaning to block forever waiting for
* a result.
* VIR_DOMAIN_QEMU_AGENT_COMMAND_DEFAULT(-1): use default timeout value.
* VIR_DOMAIN_QEMU_AGENT_COMMAND_NOWAIT(0): does not wait.
* positive value: wait for @timeout seconds
*
* Returns strings if success, NULL in failure.
*/
char *
virDomainQemuAgentCommand(virDomainPtr domain,
const char *cmd,
int timeout,
unsigned int flags)
{
virConnectPtr conn;
char *ret;
VIR_DOMAIN_DEBUG(domain, "cmd=%s, timeout=%d, flags=%x",
cmd, timeout, flags);
virResetLastError();
virCheckDomainReturn(domain, NULL);
conn = domain->conn;
virCheckReadOnlyGoto(conn->flags, error);
if (conn->driver->domainQemuAgentCommand) {
ret = conn->driver->domainQemuAgentCommand(domain, cmd,
timeout, flags);
if (!ret)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return NULL;
}
/**
* virDomainLxcEnterNamespace:
* @domain: a domain object
* @nfdlist: number of FDs in @fdlist
* @fdlist: list of namespace file descriptors
* @noldfdlist: filled with number of old FDs
* @oldfdlist: pointer to hold list of old namespace file descriptors
* @flags: currently unused, pass 0
*
* This API is LXC specific, so it will only work with hypervisor
* connections to the LXC driver.
*
* Attaches the process to the namespaces associated
* with the FDs in @fdlist
*
* If @oldfdlist is non-NULL, it will be populated with file
* descriptors representing the old namespace. This allows
* the caller to switch back to its current namespace later
*
* Returns 0 on success, -1 on error
*/
int
virDomainLxcEnterNamespace(virDomainPtr domain,
unsigned int nfdlist,
int *fdlist,
unsigned int *noldfdlist,
int **oldfdlist,
unsigned int flags)
{
size_t i;
VIR_DOMAIN_DEBUG(domain, "nfdlist=%d, fdlist=%p, "
"noldfdlist=%p, oldfdlist=%p, flags=%x",
nfdlist, fdlist, noldfdlist, oldfdlist, flags);
virResetLastError();
virCheckFlagsGoto(0, error);
if (noldfdlist && oldfdlist) {
size_t nfds;
if (virProcessGetNamespaces(getpid(),
&nfds,
oldfdlist) < 0)
goto error;
*noldfdlist = nfds;
}
if (virProcessSetNamespaces(nfdlist, fdlist) < 0) {
if (oldfdlist && noldfdlist) {
for (i = 0; i < *noldfdlist; i++)
VIR_FORCE_CLOSE((*oldfdlist)[i]);
VIR_FREE(*oldfdlist);
*noldfdlist = 0;
}
goto error;
}
return 0;
error:
virDispatchError(domain->conn);
return -1;
}
/**
* virDomainSnapshotCreateXML:
* @domain: a domain object
* @xmlDesc: string containing an XML description of the domain snapshot
* @flags: bitwise-OR of virDomainSnapshotCreateFlags
*
* Creates a new snapshot of a domain based on the snapshot xml
* contained in xmlDesc, with a top-level element <domainsnapshot>.
*
* If @flags is 0, the domain can be active, in which case the
* snapshot will be a full system snapshot (capturing both disk state,
* and runtime VM state such as RAM contents), where reverting to the
* snapshot is
* the same as resuming from hibernation (TCP connections may have
* timed out, but everything else picks up where it left off); or
* the domain can be inactive, in which case the snapshot includes
* just the disk state prior to booting. The newly created snapshot
* becomes current (see virDomainSnapshotCurrent()), and is a child
* of any previous current snapshot.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE, then this
* is a request to reinstate snapshot metadata that was previously
* captured from virDomainSnapshotGetXMLDesc() before removing that
* metadata, rather than creating a new snapshot. This can be used to
* recreate a snapshot hierarchy on a destination, then remove it on
* the source, in order to allow migration (since migration normally
* fails if snapshot metadata still remains on the source machine).
* Note that while original creation can omit a number of elements
* from @xmlDesc (and libvirt will supply sane defaults based on the
* domain state at that point in time), a redefinition must supply
* more elements (as the domain may have changed in the meantime, so
* that libvirt no longer has a way to resupply correct
* defaults). When redefining snapshot metadata, the domain's current
* snapshot will not be altered unless the
* VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT flag is also present. It is an
* error to request the VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT flag
* without VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE. On some hypervisors,
* redefining an existing snapshot can be used to alter host-specific
* portions of the domain XML to be used during revert (such as
* backing filenames associated with disk devices), but must not alter
* guest-visible layout. When redefining a snapshot name that does
* not exist, the hypervisor may validate that reverting to the
* snapshot appears to be possible (for example, disk images have
* snapshot contents by the requested name). Not all hypervisors
* support these flags.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA, then the
* domain's disk images are modified according to @xmlDesc, but
* libvirt does not track any metadata (similar to immediately calling
* virDomainSnapshotDelete() with
* VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY). This flag is
* incompatible with VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_HALT, then the domain
* will be inactive after the snapshot completes, regardless of whether
* it was active before; otherwise, a running domain will still be
* running after the snapshot. This flag is invalid on transient domains,
* and is incompatible with VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_LIVE, then the domain
* is not paused while creating the snapshot. This increases the size
* of the memory dump file, but reduces downtime of the guest while
* taking the snapshot. Some hypervisors only support this flag during
* external snapshots.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY, then the
* snapshot will be limited to the disks described in @xmlDesc, and no
* VM state will be saved. For an active guest, the disk image may be
* inconsistent (as if power had been pulled), and specifying this
* with the VIR_DOMAIN_SNAPSHOT_CREATE_HALT flag risks data loss.
*
* If @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE, then the
* libvirt will attempt to use guest agent to freeze and thaw all
* file systems in use within domain OS. However, if the guest agent
* is not present, an error is thrown. Moreover, this flag requires
* VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY to be passed as well.
*
* By default, if the snapshot involves external files, and any of the
* destination files already exist as a non-empty regular file, the
* snapshot is rejected to avoid losing contents of those files.
* However, if @flags includes VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT,
* then the destination files must be pre-created manually with
* the correct image format and metadata including backing store path
* (this allows a management app to pre-create files with relative backing
* file names, rather than the default of creating with absolute backing
* file names). Note that only the file specified in the snapshot XML is
* inserted as a snapshot thus setting incorrect metadata in the pre-created
* image may lead to the VM being unable to start or other block jobs may fail.
*
* Be aware that although libvirt prefers to report errors up front with
* no other effect, some hypervisors have certain types of failures where
* the overall command can easily fail even though the guest configuration
* was partially altered (for example, if a disk snapshot request for two
* disks fails on the second disk, but the first disk alteration cannot be
* rolled back). If this API call fails, it is therefore normally
* necessary to follow up with virDomainGetXMLDesc() and check each disk
* to determine if any partial changes occurred. However, if @flags
* contains VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC, then libvirt guarantees
* that this command will not alter any disks unless the entire set of
* changes can be done atomically, making failure recovery simpler (note
* that it is still possible to fail after disks have changed, but only
* in the much rarer cases of running out of memory or disk space).
*
* Some hypervisors may prevent this operation if there is a current
* block copy operation; in that case, use virDomainBlockJobAbort()
* to stop the block copy first.
*
* virDomainSnapshotFree should be used to free the resources after the
* snapshot object is no longer needed.
*
* Returns an (opaque) new virDomainSnapshotPtr on success or NULL on
* failure.
*/
virDomainSnapshotPtr
virDomainSnapshotCreateXML(virDomainPtr domain,
const char *xmlDesc,
unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "xmlDesc=%s, flags=0x%x", xmlDesc, flags);
virResetLastError();
virCheckDomainReturn(domain, NULL);
conn = domain->conn;
virCheckNonNullArgGoto(xmlDesc, error);
virCheckReadOnlyGoto(conn->flags, error);
VIR_REQUIRE_FLAG_GOTO(VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT,
VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE,
error);
VIR_EXCLUSIVE_FLAGS_GOTO(VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE,
VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA,
error);
VIR_EXCLUSIVE_FLAGS_GOTO(VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE,
VIR_DOMAIN_SNAPSHOT_CREATE_HALT,
error);
if (conn->driver->domainSnapshotCreateXML) {
virDomainSnapshotPtr ret;
ret = conn->driver->domainSnapshotCreateXML(domain, xmlDesc, flags);
if (!ret)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return NULL;
}
/**
* virDomainHasCurrentSnapshot:
* @domain: pointer to the domain object
* @flags: extra flags; not used yet, so callers should always pass 0
*
* Determine if the domain has a current snapshot.
*
* Returns 1 if such snapshot exists, 0 if it doesn't, -1 on error.
*/
int
virDomainHasCurrentSnapshot(virDomainPtr domain, unsigned int flags)
{
virConnectPtr conn;
VIR_DOMAIN_DEBUG(domain, "flags=0x%x", flags);
virResetLastError();
virCheckDomainReturn(domain, -1);
conn = domain->conn;
if (conn->driver->domainHasCurrentSnapshot) {
int ret = conn->driver->domainHasCurrentSnapshot(domain, flags);
if (ret < 0)
goto error;
return ret;
}
virReportUnsupportedError();
error:
virDispatchError(conn);
return -1;
}
