|  | menu "Xen driver support" | 
|  | depends on XEN | 
|  |  | 
|  | config XEN_BALLOON | 
|  | bool "Xen memory balloon driver" | 
|  | default y | 
|  | help | 
|  | The balloon driver allows the Xen domain to request more memory from | 
|  | the system to expand the domain's memory allocation, or alternatively | 
|  | return unneeded memory to the system. | 
|  |  | 
|  | config XEN_SELFBALLOONING | 
|  | bool "Dynamically self-balloon kernel memory to target" | 
|  | depends on XEN && XEN_BALLOON && CLEANCACHE && SWAP && XEN_TMEM | 
|  | default n | 
|  | help | 
|  | Self-ballooning dynamically balloons available kernel memory driven | 
|  | by the current usage of anonymous memory ("committed AS") and | 
|  | controlled by various sysfs-settable parameters.  Configuring | 
|  | FRONTSWAP is highly recommended; if it is not configured, self- | 
|  | ballooning is disabled by default but can be enabled with the | 
|  | 'selfballooning' kernel boot parameter.  If FRONTSWAP is configured, | 
|  | frontswap-selfshrinking is enabled by default but can be disabled | 
|  | with the 'noselfshrink' kernel boot parameter; and self-ballooning | 
|  | is enabled by default but can be disabled with the 'noselfballooning' | 
|  | kernel boot parameter.  Note that systems without a sufficiently | 
|  | large swap device should not enable self-ballooning. | 
|  |  | 
|  | config XEN_BALLOON_MEMORY_HOTPLUG | 
|  | bool "Memory hotplug support for Xen balloon driver" | 
|  | default n | 
|  | depends on XEN_BALLOON && MEMORY_HOTPLUG | 
|  | help | 
|  | Memory hotplug support for Xen balloon driver allows expanding memory | 
|  | available for the system above limit declared at system startup. | 
|  | It is very useful on critical systems which require long | 
|  | run without rebooting. | 
|  |  | 
|  | Memory could be hotplugged in following steps: | 
|  |  | 
|  | 1) dom0: xl mem-max <domU> <maxmem> | 
|  | where <maxmem> is >= requested memory size, | 
|  |  | 
|  | 2) dom0: xl mem-set <domU> <memory> | 
|  | where <memory> is requested memory size; alternatively memory | 
|  | could be added by writing proper value to | 
|  | /sys/devices/system/xen_memory/xen_memory0/target or | 
|  | /sys/devices/system/xen_memory/xen_memory0/target_kb on dumU, | 
|  |  | 
|  | 3) domU: for i in /sys/devices/system/memory/memory*/state; do \ | 
|  | [ "`cat "$i"`" = offline ] && echo online > "$i"; done | 
|  |  | 
|  | Memory could be onlined automatically on domU by adding following line to udev rules: | 
|  |  | 
|  | SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'" | 
|  |  | 
|  | In that case step 3 should be omitted. | 
|  |  | 
|  | config XEN_SCRUB_PAGES | 
|  | bool "Scrub pages before returning them to system" | 
|  | depends on XEN_BALLOON | 
|  | default y | 
|  | help | 
|  | Scrub pages before returning them to the system for reuse by | 
|  | other domains.  This makes sure that any confidential data | 
|  | is not accidentally visible to other domains.  Is it more | 
|  | secure, but slightly less efficient. | 
|  | If in doubt, say yes. | 
|  |  | 
|  | config XEN_DEV_EVTCHN | 
|  | tristate "Xen /dev/xen/evtchn device" | 
|  | default y | 
|  | help | 
|  | The evtchn driver allows a userspace process to trigger event | 
|  | channels and to receive notification of an event channel | 
|  | firing. | 
|  | If in doubt, say yes. | 
|  |  | 
|  | config XEN_BACKEND | 
|  | bool "Backend driver support" | 
|  | depends on XEN_DOM0 | 
|  | default y | 
|  | help | 
|  | Support for backend device drivers that provide I/O services | 
|  | to other virtual machines. | 
|  |  | 
|  | config XENFS | 
|  | tristate "Xen filesystem" | 
|  | select XEN_PRIVCMD | 
|  | default y | 
|  | help | 
|  | The xen filesystem provides a way for domains to share | 
|  | information with each other and with the hypervisor. | 
|  | For example, by reading and writing the "xenbus" file, guests | 
|  | may pass arbitrary information to the initial domain. | 
|  | If in doubt, say yes. | 
|  |  | 
|  | config XEN_COMPAT_XENFS | 
|  | bool "Create compatibility mount point /proc/xen" | 
|  | depends on XENFS | 
|  | default y | 
|  | help | 
|  | The old xenstore userspace tools expect to find "xenbus" | 
|  | under /proc/xen, but "xenbus" is now found at the root of the | 
|  | xenfs filesystem.  Selecting this causes the kernel to create | 
|  | the compatibility mount point /proc/xen if it is running on | 
|  | a xen platform. | 
|  | If in doubt, say yes. | 
|  |  | 
|  | config XEN_SYS_HYPERVISOR | 
|  | bool "Create xen entries under /sys/hypervisor" | 
|  | depends on SYSFS | 
|  | select SYS_HYPERVISOR | 
|  | default y | 
|  | help | 
|  | Create entries under /sys/hypervisor describing the Xen | 
|  | hypervisor environment.  When running native or in another | 
|  | virtual environment, /sys/hypervisor will still be present, | 
|  | but will have no xen contents. | 
|  |  | 
|  | config XEN_XENBUS_FRONTEND | 
|  | tristate | 
|  |  | 
|  | config XEN_GNTDEV | 
|  | tristate "userspace grant access device driver" | 
|  | depends on XEN | 
|  | default m | 
|  | select MMU_NOTIFIER | 
|  | help | 
|  | Allows userspace processes to use grants. | 
|  |  | 
|  | config XEN_GRANT_DEV_ALLOC | 
|  | tristate "User-space grant reference allocator driver" | 
|  | depends on XEN | 
|  | default m | 
|  | help | 
|  | Allows userspace processes to create pages with access granted | 
|  | to other domains. This can be used to implement frontend drivers | 
|  | or as part of an inter-domain shared memory channel. | 
|  |  | 
|  | config SWIOTLB_XEN | 
|  | def_bool y | 
|  | depends on PCI | 
|  | select SWIOTLB | 
|  |  | 
|  | config XEN_TMEM | 
|  | bool | 
|  | default y if (CLEANCACHE || FRONTSWAP) | 
|  | help | 
|  | Shim to interface in-kernel Transcendent Memory hooks | 
|  | (e.g. cleancache and frontswap) to Xen tmem hypercalls. | 
|  |  | 
|  | config XEN_PCIDEV_BACKEND | 
|  | tristate "Xen PCI-device backend driver" | 
|  | depends on PCI && X86 && XEN | 
|  | depends on XEN_BACKEND | 
|  | default m | 
|  | help | 
|  | The PCI device backend driver allows the kernel to export arbitrary | 
|  | PCI devices to other guests. If you select this to be a module, you | 
|  | will need to make sure no other driver has bound to the device(s) | 
|  | you want to make visible to other guests. | 
|  |  | 
|  | The parameter "passthrough" allows you specify how you want the PCI | 
|  | devices to appear in the guest. You can choose the default (0) where | 
|  | PCI topology starts at 00.00.0, or (1) for passthrough if you want | 
|  | the PCI devices topology appear the same as in the host. | 
|  |  | 
|  | The "hide" parameter (only applicable if backend driver is compiled | 
|  | into the kernel) allows you to bind the PCI devices to this module | 
|  | from the default device drivers. The argument is the list of PCI BDFs: | 
|  | xen-pciback.hide=(03:00.0)(04:00.0) | 
|  |  | 
|  | If in doubt, say m. | 
|  |  | 
|  | config XEN_PRIVCMD | 
|  | tristate | 
|  | depends on XEN | 
|  | default m | 
|  |  | 
|  | config XEN_ACPI_PROCESSOR | 
|  | tristate "Xen ACPI processor" | 
|  | depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ | 
|  | default m | 
|  | help | 
|  | This ACPI processor uploads Power Management information to the Xen | 
|  | hypervisor. | 
|  |  | 
|  | To do that the driver parses the Power Management data and uploads | 
|  | said information to the Xen hypervisor. Then the Xen hypervisor can | 
|  | select the proper Cx and Pxx states. It also registers itslef as the | 
|  | SMM so that other drivers (such as ACPI cpufreq scaling driver) will | 
|  | not load. | 
|  |  | 
|  | To compile this driver as a module, choose M here: the module will be | 
|  | called xen_acpi_processor  If you do not know what to choose, select | 
|  | M here. If the CPUFREQ drivers are built in, select Y here. | 
|  |  | 
|  | endmenu |