1menu "Xen driver support"
   2        depends on XEN
   4config XEN_BALLOON
   5        bool "Xen memory balloon driver"
   6        depends on !ARM
   7        default y
   8        help
   9          The balloon driver allows the Xen domain to request more memory from
  10          the system to expand the domain's memory allocation, or alternatively
  11          return unneeded memory to the system.
  14        bool "Dynamically self-balloon kernel memory to target"
  15        depends on XEN && XEN_BALLOON && CLEANCACHE && SWAP && XEN_TMEM
  16        default n
  17        help
  18          Self-ballooning dynamically balloons available kernel memory driven
  19          by the current usage of anonymous memory ("committed AS") and
  20          controlled by various sysfs-settable parameters.  Configuring
  21          FRONTSWAP is highly recommended; if it is not configured, self-
  22          ballooning is disabled by default but can be enabled with the
  23          'selfballooning' kernel boot parameter.  If FRONTSWAP is configured,
  24          frontswap-selfshrinking is enabled by default but can be disabled
  25          with the 'noselfshrink' kernel boot parameter; and self-ballooning
  26          is enabled by default but can be disabled with the 'noselfballooning'
  27          kernel boot parameter.  Note that systems without a sufficiently
  28          large swap device should not enable self-ballooning.
  31        bool "Memory hotplug support for Xen balloon driver"
  32        default n
  33        depends on XEN_BALLOON && MEMORY_HOTPLUG
  34        help
  35          Memory hotplug support for Xen balloon driver allows expanding memory
  36          available for the system above limit declared at system startup.
  37          It is very useful on critical systems which require long
  38          run without rebooting.
  40          Memory could be hotplugged in following steps:
  42            1) dom0: xl mem-max <domU> <maxmem>
  43               where <maxmem> is >= requested memory size,
  45            2) dom0: xl mem-set <domU> <memory>
  46               where <memory> is requested memory size; alternatively memory
  47               could be added by writing proper value to
  48               /sys/devices/system/xen_memory/xen_memory0/target or
  49               /sys/devices/system/xen_memory/xen_memory0/target_kb on dumU,
  51            3) domU: for i in /sys/devices/system/memory/memory*/state; do \
  52                       [ "`cat "$i"`" = offline ] && echo online > "$i"; done
  54          Memory could be onlined automatically on domU by adding following line to udev rules:
  56          SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"
  58          In that case step 3 should be omitted.
  60config XEN_SCRUB_PAGES
  61        bool "Scrub pages before returning them to system"
  62        depends on XEN_BALLOON
  63        default y
  64        help
  65          Scrub pages before returning them to the system for reuse by
  66          other domains.  This makes sure that any confidential data
  67          is not accidentally visible to other domains.  Is it more
  68          secure, but slightly less efficient.
  69          If in doubt, say yes.
  71config XEN_DEV_EVTCHN
  72        tristate "Xen /dev/xen/evtchn device"
  73        default y
  74        help
  75          The evtchn driver allows a userspace process to trigger event
  76          channels and to receive notification of an event channel
  77          firing.
  78          If in doubt, say yes.
  80config XEN_BACKEND
  81        bool "Backend driver support"
  82        depends on XEN_DOM0
  83        default y
  84        help
  85          Support for backend device drivers that provide I/O services
  86          to other virtual machines.
  88config XENFS
  89        tristate "Xen filesystem"
  90        select XEN_PRIVCMD
  91        default y
  92        help
  93          The xen filesystem provides a way for domains to share
  94          information with each other and with the hypervisor.
  95          For example, by reading and writing the "xenbus" file, guests
  96          may pass arbitrary information to the initial domain.
  97          If in doubt, say yes.
 100       bool "Create compatibility mount point /proc/xen"
 101       depends on XENFS
 102       default y
 103       help
 104         The old xenstore userspace tools expect to find "xenbus"
 105         under /proc/xen, but "xenbus" is now found at the root of the
 106         xenfs filesystem.  Selecting this causes the kernel to create
 107         the compatibility mount point /proc/xen if it is running on
 108         a xen platform.
 109         If in doubt, say yes.
 112       bool "Create xen entries under /sys/hypervisor"
 113       depends on SYSFS
 114       select SYS_HYPERVISOR
 115       default y
 116       help
 117         Create entries under /sys/hypervisor describing the Xen
 118         hypervisor environment.  When running native or in another
 119         virtual environment, /sys/hypervisor will still be present,
 120         but will have no xen contents.
 123        tristate
 125config XEN_GNTDEV
 126        tristate "userspace grant access device driver"
 127        depends on XEN
 128        default m
 129        select MMU_NOTIFIER
 130        help
 131          Allows userspace processes to use grants.
 134        tristate "User-space grant reference allocator driver"
 135        depends on XEN
 136        default m
 137        help
 138          Allows userspace processes to create pages with access granted
 139          to other domains. This can be used to implement frontend drivers
 140          or as part of an inter-domain shared memory channel.
 142config SWIOTLB_XEN
 143        def_bool y
 144        depends on PCI
 145        select SWIOTLB
 147config XEN_TMEM
 148        bool
 149        depends on !ARM
 150        default y if (CLEANCACHE || FRONTSWAP)
 151        help
 152          Shim to interface in-kernel Transcendent Memory hooks
 153          (e.g. cleancache and frontswap) to Xen tmem hypercalls.
 156        tristate "Xen PCI-device backend driver"
 157        depends on PCI && X86 && XEN
 158        depends on XEN_BACKEND
 159        default m
 160        help
 161          The PCI device backend driver allows the kernel to export arbitrary
 162          PCI devices to other guests. If you select this to be a module, you
 163          will need to make sure no other driver has bound to the device(s)
 164          you want to make visible to other guests.
 166          The parameter "passthrough" allows you specify how you want the PCI
 167          devices to appear in the guest. You can choose the default (0) where
 168          PCI topology starts at 00.00.0, or (1) for passthrough if you want
 169          the PCI devices topology appear the same as in the host.
 171          The "hide" parameter (only applicable if backend driver is compiled
 172          into the kernel) allows you to bind the PCI devices to this module
 173          from the default device drivers. The argument is the list of PCI BDFs:
 174          xen-pciback.hide=(03:00.0)(04:00.0)
 176          If in doubt, say m.
 178config XEN_PRIVCMD
 179        tristate
 180        depends on XEN
 181        default m
 184        tristate "Xen ACPI processor"
 185        depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ
 186        default m
 187        help
 188          This ACPI processor uploads Power Management information to the Xen
 189          hypervisor.
 191          To do that the driver parses the Power Management data and uploads
 192          said information to the Xen hypervisor. Then the Xen hypervisor can
 193          select the proper Cx and Pxx states. It also registers itslef as the
 194          SMM so that other drivers (such as ACPI cpufreq scaling driver) will
 195          not load.
 197          To compile this driver as a module, choose M here: the module will be
 198          called xen_acpi_processor  If you do not know what to choose, select
 199          M here. If the CPUFREQ drivers are built in, select Y here.
 201config XEN_MCE_LOG
 202        bool "Xen platform mcelog"
 203        depends on XEN_DOM0 && X86_64 && X86_MCE
 204        default n
 205        help
 206          Allow kernel fetching MCE error from Xen platform and
 207          converting it into Linux mcelog format for mcelog tools
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