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 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.
  29
  30 config XEN_BALLOON_MEMORY_HOTPLUG
  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.
  39
  40           Memory could be hotplugged in following steps:
  41
  42             1) dom0: xl mem-max <domU> <maxmem>
  43                where <maxmem> is >= requested memory size,
  44
  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,
  50
  51             3) domU: for i in /sys/devices/system/memory/memory*/state; do \
  52                        [ "`cat "$i"`" = offline ] && echo online > "$i"; done
  53
  54           Memory could be onlined automatically on domU by adding following line to udev rules:
  55
  56           SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"
  57
  58           In that case step 3 should be omitted.
  59
  60 config 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.
  70
  71 config 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.
  79
  80 config 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.
  87
  88 config 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.
  98
  99 config XEN_COMPAT_XENFS
 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.
 110
 111 config XEN_SYS_HYPERVISOR
 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.
 121
 122 config XEN_XENBUS_FRONTEND
 123         tristate
 124
 125 config 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.
 132
 133 config XEN_GRANT_DEV_ALLOC
 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.
 141
 142 config SWIOTLB_XEN
 143         def_bool y
 144         depends on PCI
 145         select SWIOTLB
 146
 147 config 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.
 154
 155 config XEN_PCIDEV_BACKEND
 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.
 165
 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.
 170
 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)
 175
 176           If in doubt, say m.
 177
 178 config XEN_PRIVCMD
 179         tristate
 180         depends on XEN
 181         default m
 182
 183 config XEN_STUB
 184         bool "Xen stub drivers"
 185         depends on XEN && X86_64
 186         default n
 187         help
 188           Allow kernel to install stub drivers, to reserve space for Xen drivers,
 189           i.e. memory hotplug and cpu hotplug, and to block native drivers loaded,
 190           so that real Xen drivers can be modular.
 191
 192           To enable Xen features like cpu and memory hotplug, select Y here.
 193
 194 config XEN_ACPI_HOTPLUG_MEMORY
 195         tristate "Xen ACPI memory hotplug"
 196         depends on XEN_DOM0 && XEN_STUB && ACPI
 197         default n
 198         help
 199           This is Xen ACPI memory hotplug.
 200
 201           Currently Xen only support ACPI memory hot-add. If you want
 202           to hot-add memory at runtime (the hot-added memory cannot be
 203           removed until machine stop), select Y/M here, otherwise select N.
 204
 205 config XEN_ACPI_HOTPLUG_CPU
 206         tristate "Xen ACPI cpu hotplug"
 207         depends on XEN_DOM0 && XEN_STUB && ACPI
 208         select ACPI_CONTAINER
 209         default n
 210         help
 211           Xen ACPI cpu enumerating and hotplugging
 212
 213           For hotplugging, currently Xen only support ACPI cpu hotadd.
 214           If you want to hotadd cpu at runtime (the hotadded cpu cannot
 215           be removed until machine stop), select Y/M here.
 216
 217 config XEN_ACPI_PROCESSOR
 218         tristate "Xen ACPI processor"
 219         depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ
 220         default m
 221         help
 222           This ACPI processor uploads Power Management information to the Xen
 223           hypervisor.
 224
 225           To do that the driver parses the Power Management data and uploads
 226           said information to the Xen hypervisor. Then the Xen hypervisor can
 227           select the proper Cx and Pxx states. It also registers itslef as the
 228           SMM so that other drivers (such as ACPI cpufreq scaling driver) will
 229           not load.
 230
 231           To compile this driver as a module, choose M here: the module will be
 232           called xen_acpi_processor  If you do not know what to choose, select
 233           M here. If the CPUFREQ drivers are built in, select Y here.
 234
 235 config XEN_MCE_LOG
 236         bool "Xen platform mcelog"
 237         depends on XEN_DOM0 && X86_64 && X86_MCE
 238         default n
 239         help
 240           Allow kernel fetching MCE error from Xen platform and
 241           converting it into Linux mcelog format for mcelog tools
 242
 243 config XEN_HAVE_PVMMU
 244        bool
 245
 246 endmenu