core interfaces for the libvirt library

Provides the interfaces of the libvirt library to handle virtualized domains Daniel Veillard <veillard@redhat.com>

error handling interfaces for the libvirt library

Provides the interfaces of the libvirt library to handle errors raised while using the library. Daniel Veillard <veillard@redhat.com> Macro providing the version of the library as version * 1,000,000 + minor * 1000 + micro This macro is to be used in conjunction with virDomainGetVcpus() and virDomainPinVcpu() APIs. VIR_COPY_CPUMAP macro extract the cpumap of the specified vcpu from cpumaps array and copy it into cpumap to be used later by virDomainPinVcpu() API. This macro is to be used in conjunction with virDomainPinVcpu() API. It returns the length (in bytes) required to store the complete CPU map between a single virtual & all physical CPUs of a domain. This macro is to be used in conjunction with virDomainGetVcpus() API. VIR_CPU_USABLE macro returns a non zero value (true) if the cpu is usable by the vcpu, and 0 otherwise. Macro providing the field length of virSchedParameter This macro is to be used in conjunction with virDomainGetVcpus() and virDomainPinVcpu() APIs. VIR_GET_CPUMAP macro returns a pointer to the cpumap of the specified vcpu from cpumaps array. This macro is to calculate the total number of CPUs supported but not necessary active in the host. This macro is to be used in conjunction with virDomainPinVcpu() API. USE_CPU macro reset the bit (CPU not usable) of the related cpu in cpumap. This macro is to be used in conjunction with virDomainPinVcpu() API. USE_CPU macro set the bit (CPU usable) of the related cpu in cpumap. This macro provides the length of the buffer required for virDomainGetUUID() This macro provides the length of the buffer required for virDomainGetUUIDString() a virConnectPtr is pointer to a virConnect private structure, this is the type used to reference a connection to the Hypervisor in the API. A pointer to a virDomainBlockStats structure a virDomainInfoPtr is a pointer to a virDomainInfo structure. A pointer to a virDomainInterfaceStats structure a virDomainPtr is pointer to a virDomain private structure, this is the type used to reference a domain in the API. a virNetworkPtr is pointer to a virNetwork private structure, this is the type used to reference a virtual network in the API. a virNodeInfoPtr is a pointer to a virNodeInfo structure. a virSchedParameterPtr is a pointer to a virSchedParameter structure. a virStoragePoolPtr is pointer to a virStoragePool private structure, this is the type used to reference a storage pool in the API. a virStorageVolPtr is pointer to a virStorageVol private structure, this is the type used to reference a storage volume in the API. Copy the content of the last error caught on that connection One will need to free the result with virResetError() Provide a pointer to the last error caught on that connection Simpler but may not be suitable for multithreaded accesses, in which case use virConnCopyLastError() Reset the last error caught on that connection Set a connection error handling function, if @handler is NULL it will reset to default which is to pass error back to the global library handler. This function closes the connection to the Hypervisor. This should not be called if further interaction with the Hypervisor are needed especially if there is running domain which need further monitoring by the application. Talks to a storage backend and attempts to auto-discover the set of available storage pool sources. e.g. For iSCSI this would be a set of iSCSI targets. For NFS this would be a list of exported paths. The srcSpec (optional for some storage pool types, e.g. local ones) is an instance of the storage pool's source element specifying where to look for the pools. srcSpec is not required for some types (e.g., those querying local storage resources only) Provides capabilities of the hypervisor / driver. This returns the system hostname on which the hypervisor is running (the result of the gethostname(2) system call). If we are connected to a remote system, then this returns the hostname of the remote system. Provides the maximum number of virtual CPUs supported for a guest VM of a specific type. The 'type' parameter here corresponds to the 'type' attribute in the <domain> element of the XML. Get the name of the Hypervisor software used. This returns the URI (name) of the hypervisor connection. Normally this is the same as or similar to the string passed to the virConnectOpen/virConnectOpenReadOnly call, but the driver may make the URI canonical. If name == NULL was passed to virConnectOpen, then the driver will return a non-NULL URI which can be used to connect to the same hypervisor later. Get the version level of the Hypervisor running. This may work only with hypervisor call, i.e. with privileged access to the hypervisor, not with a Read-Only connection. list the defined but inactive domains, stores the pointers to the names in @names list the inactive networks, stores the pointers to the names in @names Provides the list of names of inactive storage pools upto maxnames. If there are more than maxnames, the remaining names will be silently ignored. Collect the list of active domains, and store their ID in @maxids Collect the list of active networks, and store their names in @names Provides the list of names of active storage pools upto maxnames. If there are more than maxnames, the remaining names will be silently ignored. Provides the number of defined but inactive domains. Provides the number of inactive networks. Provides the number of inactive storage pools Provides the number of active domains. Provides the number of active networks. Provides the number of active storage pools This function should be called first to get a connection to the Hypervisor and xen store This function should be called first to get a connection to the Hypervisor. If necessary, authentication will be performed fetching credentials via the callback This function should be called first to get a restricted connection to the library functionalities. The set of APIs usable are then restricted on the available methods to control the domains. Copy the content of the last error caught at the library level One will need to free the result with virResetError() Default routine reporting an error to stderr. Create a virtual device attachment to backend. This function allows you to read the contents of a domain's disk device. Typical uses for this are to determine if the domain has written a Master Boot Record (indicating that the domain has completed installation), or to try to work out the state of the domain's filesystems. (Note that in the local case you might try to open the block device or file directly, but that won't work in the remote case, nor if you don't have sufficient permission. Hence the need for this call). 'path' must be a device or file corresponding to the domain. In other words it must be the precise string returned in a <disk><source dev='...'/></disk> from virDomainGetXMLDesc. 'offset' and 'size' represent an area which must lie entirely within the device or file. 'size' may be 0 to test if the call would succeed. 'buffer' is the return buffer and must be at least 'size' bytes. NB. The remote driver imposes a 64K byte limit on 'size'. For your program to be able to work reliably over a remote connection you should split large requests to <= 65536 bytes. This function returns block device (disk) stats for block devices attached to the domain. The path parameter is the name of the block device. Get this by calling virDomainGetXMLDesc and finding the <target dev='...'> attribute within //domain/devices/disk. (For example, "xvda"). Domains may have more than one block device. To get stats for each you should make multiple calls to this function. Individual fields within the stats structure may be returned as -1, which indicates that the hypervisor does not support that particular statistic. This method will dump the core of a domain on a given file for analysis. Note that for remote Xen Daemon the file path will be interpreted in the remote host. launch a defined domain. If the call succeed the domain moves from the defined to the running domains pools. Launch a new Linux guest domain, based on an XML description similar to the one returned by virDomainGetXMLDesc() This function may requires privileged access to the hypervisor. The domain is not persistent, so its definition will disappear when it is destroyed, or if the host is restarted (see virDomainDefineXML() to define persistent domains). Define a domain, but does not start it. This definition is persistent, until explicitly undefined with virDomainUndefine(). Destroy the domain object. The running instance is shutdown if not down already and all resources used by it are given back to the hypervisor. This does not free the associated virDomainPtr object. This function may require privileged access Destroy a virtual device attachment to backend. Free the domain object. The running instance is kept alive. The data structure is freed and should not be used thereafter. Provides a boolean value indicating whether the domain configured to be automatically started when the host machine boots. Provides the connection pointer associated with a domain. The reference counter on the connection is not increased by this call. WARNING: When writing libvirt bindings in other languages, do not use this function. Instead, store the connection and the domain object together. Get the hypervisor ID number for the domain Extract information about a domain. Note that if the connection used to get the domain is limited only a partial set of the information can be extracted. Retrieve the maximum amount of physical memory allocated to a domain. If domain is NULL, then this get the amount of memory reserved to Domain0 i.e. the domain where the application runs. Provides the maximum number of virtual CPUs supported for the guest VM. If the guest is inactive, this is basically the same as virConnectGetMaxVcpus. If the guest is running this will reflect the maximum number of virtual CPUs the guest was booted with. Get the public name for that domain Get the type of domain operation system. Get the scheduler parameters, the @params array will be filled with the values. Get the scheduler type. Get the UUID for a domain Get the UUID for a domain as string. For more information about UUID see RFC4122. Extract information about virtual CPUs of domain, store it in info array and also in cpumaps if this pointer isn't NULL. Provide an XML description of the domain. The description may be reused later to relaunch the domain with virDomainCreateLinux(). This function returns network interface stats for interfaces attached to the domain. The path parameter is the name of the network interface. Domains may have more than network interface. To get stats for each you should make multiple calls to this function. Individual fields within the stats structure may be returned as -1, which indicates that the hypervisor does not support that particular statistic. Try to find a domain based on the hypervisor ID number Note that this won't work for inactive domains which have an ID of -1, in that case a lookup based on the Name or UUId need to be done instead. Try to lookup a domain on the given hypervisor based on its name. Try to lookup a domain on the given hypervisor based on its UUID. Try to lookup a domain on the given hypervisor based on its UUID. This function allows you to read the contents of a domain's memory. The memory which is read is controlled by the 'start', 'size' and 'flags' parameters. If 'flags' is VIR_MEMORY_VIRTUAL then the 'start' and 'size' parameters are interpreted as virtual memory addresses for whichever task happens to be running on the domain at the moment. Although this sounds haphazard it is in fact what you want in order to read Linux kernel state, because it ensures that pointers in the kernel image can be interpreted coherently. 'buffer' is the return buffer and must be at least 'size' bytes. 'size' may be 0 to test if the call would succeed. NB. The remote driver imposes a 64K byte limit on 'size'. For your program to be able to work reliably over a remote connection you should split large requests to <= 65536 bytes. Migrate the domain object from its current host to the destination host given by dconn (a connection to the destination host). Flags may be one of more of the following: VIR_MIGRATE_LIVE Attempt a live migration. If a hypervisor supports renaming domains during migration, then you may set the dname parameter to the new name (otherwise it keeps the same name). If this is not supported by the hypervisor, dname must be NULL or else you will get an error. Since typically the two hypervisors connect directly to each other in order to perform the migration, you may need to specify a path from the source to the destination. This is the purpose of the uri parameter. If uri is NULL, then libvirt will try to find the best method. Uri may specify the hostname or IP address of the destination host as seen from the source. Or uri may be a URI giving transport, hostname, user, port, etc. in the usual form. Refer to driver documentation for the particular URIs supported. The maximum bandwidth (in Mbps) that will be used to do migration can be specified with the bandwidth parameter. If set to 0, libvirt will choose a suitable default. Some hypervisors do not support this feature and will return an error if bandwidth is not 0. To see which features are supported by the current hypervisor, see virConnectGetCapabilities, /capabilities/host/migration_features. There are many limitations on migration imposed by the underlying technology - for example it may not be possible to migrate between different processors even with the same architecture, or between different types of hypervisor. Dynamically change the real CPUs which can be allocated to a virtual CPU. This function requires privileged access to the hypervisor. Reboot a domain, the domain object is still usable there after but the domain OS is being stopped for a restart. Note that the guest OS may ignore the request. This method will restore a domain saved to disk by virDomainSave(). Resume an suspended domain, the process is restarted from the state where it was frozen by calling virSuspendDomain(). This function may requires privileged access This method will suspend a domain and save its memory contents to a file on disk. After the call, if successful, the domain is not listed as running anymore (this may be a problem). Use virDomainRestore() to restore a domain after saving. Configure the domain to be automatically started when the host machine boots. Dynamically change the maximum amount of physical memory allocated to a domain. If domain is NULL, then this change the amount of memory reserved to Domain0 i.e. the domain where the application runs. This function requires privileged access to the hypervisor. Dynamically change the target amount of physical memory allocated to a domain. If domain is NULL, then this change the amount of memory reserved to Domain0 i.e. the domain where the application runs. This function may requires privileged access to the hypervisor. Change the scheduler parameters Dynamically change the number of virtual CPUs used by the domain. Note that this call may fail if the underlying virtualization hypervisor does not support it or if growing the number is arbitrary limited. This function requires privileged access to the hypervisor. Shutdown a domain, the domain object is still usable there after but the domain OS is being stopped. Note that the guest OS may ignore the request. TODO: should we add an option for reboot, knowing it may not be doable in the general case ? Suspends an active domain, the process is frozen without further access to CPU resources and I/O but the memory used by the domain at the hypervisor level will stay allocated. Use virDomainResume() to reactivate the domain. This function may requires privileged access. Undefine a domain but does not stop it if it is running Signature of a function to use when there is an error raised by the library. Provide a pointer to the last error caught at the library level Simpler but may not be suitable for multithreaded accesses, in which case use virCopyLastError() Provides two information back, @libVer is the version of the library while @typeVer will be the version of the hypervisor type @type against which the library was compiled. If @type is NULL, "Xen" is assumed, if @type is unknown or not available, an error code will be returned and @typeVer will be 0. Initialize the library. It's better to call this routine at startup in multithreaded applications to avoid potential race when initializing the library. Create and start a defined network. If the call succeed the network moves from the defined to the running networks pools. Create and start a new virtual network, based on an XML description similar to the one returned by virNetworkGetXMLDesc() Define a network, but does not create it Destroy the network object. The running instance is shutdown if not down already and all resources used by it are given back to the hypervisor. This does not free the associated virNetworkPtr object. This function may require privileged access Free the network object. The running instance is kept alive. The data structure is freed and should not be used thereafter. Provides a boolean value indicating whether the network configured to be automatically started when the host machine boots. Provides a bridge interface name to which a domain may connect a network interface in order to join the network. Provides the connection pointer associated with a network. The reference counter on the connection is not increased by this call. WARNING: When writing libvirt bindings in other languages, do not use this function. Instead, store the connection and the network object together. Get the public name for that network Get the UUID for a network Get the UUID for a network as string. For more information about UUID see RFC4122. Provide an XML description of the network. The description may be reused later to relaunch the network with virNetworkCreateXML(). Try to lookup a network on the given hypervisor based on its name. Try to lookup a network on the given hypervisor based on its UUID. Try to lookup a network on the given hypervisor based on its UUID. Configure the network to be automatically started when the host machine boots. Undefine a network but does not stop it if it is running This call returns the amount of free memory in one or more NUMA cells. The @freeMems array must be allocated by the caller and will be filled with the amount of free memory in kilobytes for each cell requested, starting with startCell (in freeMems[0]), up to either (startCell + maxCells), or the number of additional cells in the node, whichever is smaller. provides the free memory available on the Node Extract hardware information about the node. Reset the error being pointed to Reset the last error caught at the library level. Set a library global error handling function, if @handler is NULL, it will reset to default printing on stderr. The error raised there are those for which no handler at the connection level could caught. Build the underlying storage pool Starts an inactive storage pool Create a new storage based on its XML description. The pool is not persistent, so its definition will disappear when it is destroyed, or if the host is restarted Define a new inactive storage pool based on its XML description. The pool is persistent, until explicitly undefined. Delete the underlying pool resources. This is a non-recoverable operation. The virStoragePoolPtr object itself is not free'd. Destroy an active storage pool. This will deactivate the pool on the host, but keep any persistent config associated with it. If it has a persistent config it can later be restarted with virStoragePoolCreate(). This does not free the associated virStoragePoolPtr object. Free a storage pool object, releasing all memory associated with it. Does not change the state of the pool on the host. Fetches the value of the autostart flag, which determines whether the pool is automatically started at boot time Provides the connection pointer associated with a storage pool. The reference counter on the connection is not increased by this call. WARNING: When writing libvirt bindings in other languages, do not use this function. Instead, store the connection and the pool object together. Get volatile information about the storage pool such as free space / usage summary Fetch the locally unique name of the storage pool Fetch the globally unique ID of the storage pool Fetch the globally unique ID of the storage pool as a string Fetch an XML document describing all aspects of the storage pool. This is suitable for later feeding back into the virStoragePoolCreateXML method. Fetch list of storage volume names, limiting to at most maxnames. Fetch a storage pool based on its unique name Fetch a storage pool based on its globally unique id Fetch a storage pool based on its globally unique id Fetch a storage pool which contains a particular volume Fetch the number of storage volumes within a pool Request that the pool refresh its list of volumes. This may involve communicating with a remote server, and/or initializing new devices at the OS layer Sets the autostart flag Undefine an inactive storage pool Create a storage volume within a pool based on an XML description. Not all pools support creation of volumes Delete the storage volume from the pool Release the storage volume handle. The underlying storage volume contains to exist Provides the connection pointer associated with a storage volume. The reference counter on the connection is not increased by this call. WARNING: When writing libvirt bindings in other languages, do not use this function. Instead, store the connection and the volume object together. Fetches volatile information about the storage volume such as its current allocation Fetch the storage volume key. This is globally unique, so the same volume will have the same key no matter what host it is accessed from Fetch the storage volume name. This is unique within the scope of a pool Fetch the storage volume path. Depending on the pool configuration this is either persistent across hosts, or dynamically assigned at pool startup. Consult pool documentation for information on getting the persistent naming Fetch an XML document describing all aspects of the storage volume Fetch a pointer to a storage volume based on its globally unique key Fetch a pointer to a storage volume based on its name within a pool Fetch a pointer to a storage volume based on its locally (host) unique path