drivers/xen/Kconfig

   1 menu "Xen driver support"
   2         depends on XEN
   3
   4 config 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.
  12
  13 config XEN_SELFBALLOONING
  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. If FRONTSWAP is configured,
  23           frontswap-selfshrinking is enabled by default but can be disabled
  24           with the 'tmem.selfshrink=0' kernel boot parameter; and self-ballooning
  25           is enabled by default but can be disabled with the 'tmem.selfballooning=0'
  26           kernel boot parameter.  Note that systems without a sufficiently
  27           large swap device should not enable self-ballooning.
  28
  29 config XEN_BALLOON_MEMORY_HOTPLUG
  30         bool "Memory hotplug support for Xen balloon driver"
  31         default n
  32         depends on XEN_BALLOON && MEMORY_HOTPLUG
  33         help
  34           Memory hotplug support for Xen balloon driver allows expanding memory
  35           available for the system above limit declared at system startup.
  36           It is very useful on critical systems which require long
  37           run without rebooting.
  38
  39           Memory could be hotplugged in following steps:
  40
  41             1) dom0: xl mem-max <domU> <maxmem>
  42                where <maxmem> is >= requested memory size,
  43
  44             2) dom0: xl mem-set <domU> <memory>
  45                where <memory> is requested memory size; alternatively memory
  46                could be added by writing proper value to
  47                /sys/devices/system/xen_memory/xen_memory0/target or
  48                /sys/devices/system/xen_memory/xen_memory0/target_kb on dumU,
  49
  50             3) domU: for i in /sys/devices/system/memory/memory*/state; do \
  51                        [ "`cat "$i"`" = offline ] && echo online > "$i"; done
  52
  53           Memory could be onlined automatically on domU by adding following line to udev rules:
  54
  55           SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"
  56
  57           In that case step 3 should be omitted.
  58
  59 config XEN_SCRUB_PAGES
  60         bool "Scrub pages before returning them to system"
  61         depends on XEN_BALLOON
  62         default y
  63         help
  64           Scrub pages before returning them to the system for reuse by
  65           other domains.  This makes sure that any confidential data
  66           is not accidentally visible to other domains.  Is it more
  67           secure, but slightly less efficient.
  68           If in doubt, say yes.
  69
  70 config XEN_DEV_EVTCHN
  71         tristate "Xen /dev/xen/evtchn device"
  72         default y
  73         help
  74           The evtchn driver allows a userspace process to trigger event
  75           channels and to receive notification of an event channel
  76           firing.
  77           If in doubt, say yes.
  78
  79 config XEN_BACKEND
  80         bool "Backend driver support"
  81         depends on XEN_DOM0
  82         default y
  83         help
  84           Support for backend device drivers that provide I/O services
  85           to other virtual machines.
  86
  87 config XENFS
  88         tristate "Xen filesystem"
  89         select XEN_PRIVCMD
  90         default y
  91         help
  92           The xen filesystem provides a way for domains to share
  93           information with each other and with the hypervisor.
  94           For example, by reading and writing the "xenbus" file, guests
  95           may pass arbitrary information to the initial domain.
  96           If in doubt, say yes.
  97
  98 config XEN_COMPAT_XENFS
  99        bool "Create compatibility mount point /proc/xen"
 100        depends on XENFS
 101        default y
 102        help
 103          The old xenstore userspace tools expect to find "xenbus"
 104          under /proc/xen, but "xenbus" is now found at the root of the
 105          xenfs filesystem.  Selecting this causes the kernel to create
 106          the compatibility mount point /proc/xen if it is running on
 107          a xen platform.
 108          If in doubt, say yes.
 109
 110 config XEN_SYS_HYPERVISOR
 111        bool "Create xen entries under /sys/hypervisor"
 112        depends on SYSFS
 113        select SYS_HYPERVISOR
 114        default y
 115        help
 116          Create entries under /sys/hypervisor describing the Xen
 117          hypervisor environment.  When running native or in another
 118          virtual environment, /sys/hypervisor will still be present,
 119          but will have no xen contents.
 120
 121 config XEN_XENBUS_FRONTEND
 122         tristate
 123
 124 config XEN_GNTDEV
 125         tristate "userspace grant access device driver"
 126         depends on XEN
 127         default m
 128         select MMU_NOTIFIER
 129         help
 130           Allows userspace processes to use grants.
 131
 132 config XEN_GRANT_DEV_ALLOC
 133         tristate "User-space grant reference allocator driver"
 134         depends on XEN
 135         default m
 136         help
 137           Allows userspace processes to create pages with access granted
 138           to other domains. This can be used to implement frontend drivers
 139           or as part of an inter-domain shared memory channel.
 140
 141 config SWIOTLB_XEN
 142         def_bool y
 143         depends on PCI && X86
 144         select SWIOTLB
 145
 146 config XEN_TMEM
 147         tristate
 148         depends on !ARM
 149         default m if (CLEANCACHE || FRONTSWAP)
 150         help
 151           Shim to interface in-kernel Transcendent Memory hooks
 152           (e.g. cleancache and frontswap) to Xen tmem hypercalls.
 153
 154 config XEN_PCIDEV_BACKEND
 155         tristate "Xen PCI-device backend driver"
 156         depends on PCI && X86 && XEN
 157         depends on XEN_BACKEND
 158         default m
 159         help
 160           The PCI device backend driver allows the kernel to export arbitrary
 161           PCI devices to other guests. If you select this to be a module, you
 162           will need to make sure no other driver has bound to the device(s)
 163           you want to make visible to other guests.
 164
 165           The parameter "passthrough" allows you specify how you want the PCI
 166           devices to appear in the guest. You can choose the default (0) where
 167           PCI topology starts at 00.00.0, or (1) for passthrough if you want
 168           the PCI devices topology appear the same as in the host.
 169
 170           The "hide" parameter (only applicable if backend driver is compiled
 171           into the kernel) allows you to bind the PCI devices to this module
 172           from the default device drivers. The argument is the list of PCI BDFs:
 173           xen-pciback.hide=(03:00.0)(04:00.0)
 174
 175           If in doubt, say m.
 176
 177 config XEN_PRIVCMD
 178         tristate
 179         depends on XEN
 180         default m
 181
 182 config XEN_STUB
 183         bool "Xen stub drivers"
 184         depends on XEN && X86_64 && BROKEN
 185         default n
 186         help
 187           Allow kernel to install stub drivers, to reserve space for Xen drivers,
 188           i.e. memory hotplug and cpu hotplug, and to block native drivers loaded,
 189           so that real Xen drivers can be modular.
 190
 191           To enable Xen features like cpu and memory hotplug, select Y here.
 192
 193 config XEN_ACPI_HOTPLUG_MEMORY
 194         tristate "Xen ACPI memory hotplug"
 195         depends on XEN_DOM0 && XEN_STUB && ACPI
 196         default n
 197         help
 198           This is Xen ACPI memory hotplug.
 199
 200           Currently Xen only support ACPI memory hot-add. If you want
 201           to hot-add memory at runtime (the hot-added memory cannot be
 202           removed until machine stop), select Y/M here, otherwise select N.
 203
 204 config XEN_ACPI_HOTPLUG_CPU
 205         tristate "Xen ACPI cpu hotplug"
 206         depends on XEN_DOM0 && XEN_STUB && ACPI
 207         select ACPI_CONTAINER
 208         default n
 209         help
 210           Xen ACPI cpu enumerating and hotplugging
 211
 212           For hotplugging, currently Xen only support ACPI cpu hotadd.
 213           If you want to hotadd cpu at runtime (the hotadded cpu cannot
 214           be removed until machine stop), select Y/M here.
 215
 216 config XEN_ACPI_PROCESSOR
 217         tristate "Xen ACPI processor"
 218         depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ
 219         default m
 220         help
 221           This ACPI processor uploads Power Management information to the Xen
 222           hypervisor.
 223
 224           To do that the driver parses the Power Management data and uploads
 225           said information to the Xen hypervisor. Then the Xen hypervisor can
 226           select the proper Cx and Pxx states. It also registers itslef as the
 227           SMM so that other drivers (such as ACPI cpufreq scaling driver) will
 228           not load.
 229
 230           To compile this driver as a module, choose M here: the module will be
 231           called xen_acpi_processor  If you do not know what to choose, select
 232           M here. If the CPUFREQ drivers are built in, select Y here.
 233
 234 config XEN_MCE_LOG
 235         bool "Xen platform mcelog"
 236         depends on XEN_DOM0 && X86_64 && X86_MCE
 237         default n
 238         help
 239           Allow kernel fetching MCE error from Xen platform and
 240           converting it into Linux mcelog format for mcelog tools
 241
 242 config XEN_HAVE_PVMMU
 243        bool
 244
 245 endmenu