1menu "Xen driver support" 2 depends on XEN 3 4config XEN_BALLOON 5 bool "Xen memory balloon driver" 6 default y 7 help 8 The balloon driver allows the Xen domain to request more memory from 9 the system to expand the domain's memory allocation, or alternatively 10 return unneeded memory to the system. 11 12config XEN_SELFBALLOONING 13 bool "Dynamically self-balloon kernel memory to target" 14 depends on XEN && XEN_BALLOON && CLEANCACHE && SWAP && XEN_TMEM 15 default n 16 help 17 Self-ballooning dynamically balloons available kernel memory driven 18 by the current usage of anonymous memory ("committed AS") and 19 controlled by various sysfs-settable parameters. Configuring 20 FRONTSWAP is highly recommended; if it is not configured, self- 21 ballooning is disabled by default. If FRONTSWAP is configured, 22 frontswap-selfshrinking is enabled by default but can be disabled 23 with the 'tmem.selfshrink=0' kernel boot parameter; and self-ballooning 24 is enabled by default but can be disabled with the 'tmem.selfballooning=0' 25 kernel boot parameter. Note that systems without a sufficiently 26 large swap device should not enable self-ballooning. 27 28config XEN_BALLOON_MEMORY_HOTPLUG 29 bool "Memory hotplug support for Xen balloon driver" 30 default n 31 depends on XEN_BALLOON && MEMORY_HOTPLUG 32 help 33 Memory hotplug support for Xen balloon driver allows expanding memory 34 available for the system above limit declared at system startup. 35 It is very useful on critical systems which require long 36 run without rebooting. 37 38 Memory could be hotplugged in following steps: 39 40 1) dom0: xl mem-max <domU> <maxmem> 41 where <maxmem> is >= requested memory size, 42 43 2) dom0: xl mem-set <domU> <memory> 44 where <memory> is requested memory size; alternatively memory 45 could be added by writing proper value to 46 /sys/devices/system/xen_memory/xen_memory0/target or 47 /sys/devices/system/xen_memory/xen_memory0/target_kb on dumU, 48 49 3) domU: for i in /sys/devices/system/memory/memory*/state; do \ 50 [ "`cat "$i"`" = offline ] && echo online > "$i"; done 51 52 Memory could be onlined automatically on domU by adding following line to udev rules: 53 54 SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'" 55 56 In that case step 3 should be omitted. 57 58config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT 59 int "Hotplugged memory limit (in GiB) for a PV guest" 60 default 512 if X86_64 61 default 4 if X86_32 62 range 0 64 if X86_32 63 depends on XEN_HAVE_PVMMU 64 depends on XEN_BALLOON_MEMORY_HOTPLUG 65 help 66 Maxmium amount of memory (in GiB) that a PV guest can be 67 expanded to when using memory hotplug. 68 69 A PV guest can have more memory than this limit if is 70 started with a larger maximum. 71 72 This value is used to allocate enough space in internal 73 tables needed for physical memory administration. 74 75config XEN_SCRUB_PAGES 76 bool "Scrub pages before returning them to system" 77 depends on XEN_BALLOON 78 default y 79 help 80 Scrub pages before returning them to the system for reuse by 81 other domains. This makes sure that any confidential data 82 is not accidentally visible to other domains. Is it more 83 secure, but slightly less efficient. 84 If in doubt, say yes. 85 86config XEN_DEV_EVTCHN 87 tristate "Xen /dev/xen/evtchn device" 88 default y 89 help 90 The evtchn driver allows a userspace process to trigger event 91 channels and to receive notification of an event channel 92 firing. 93 If in doubt, say yes. 94 95config XEN_BACKEND 96 bool "Backend driver support" 97 depends on XEN_DOM0 98 default y 99 help 100 Support for backend device drivers that provide I/O services 101 to other virtual machines. 102 103config XENFS 104 tristate "Xen filesystem" 105 select XEN_PRIVCMD 106 default y 107 help 108 The xen filesystem provides a way for domains to share 109 information with each other and with the hypervisor. 110 For example, by reading and writing the "xenbus" file, guests 111 may pass arbitrary information to the initial domain. 112 If in doubt, say yes. 113 114config XEN_COMPAT_XENFS 115 bool "Create compatibility mount point /proc/xen" 116 depends on XENFS 117 default y 118 help 119 The old xenstore userspace tools expect to find "xenbus" 120 under /proc/xen, but "xenbus" is now found at the root of the 121 xenfs filesystem. Selecting this causes the kernel to create 122 the compatibility mount point /proc/xen if it is running on 123 a xen platform. 124 If in doubt, say yes. 125 126config XEN_SYS_HYPERVISOR 127 bool "Create xen entries under /sys/hypervisor" 128 depends on SYSFS 129 select SYS_HYPERVISOR 130 default y 131 help 132 Create entries under /sys/hypervisor describing the Xen 133 hypervisor environment. When running native or in another 134 virtual environment, /sys/hypervisor will still be present, 135 but will have no xen contents. 136 137config XEN_XENBUS_FRONTEND 138 tristate 139 140config XEN_GNTDEV 141 tristate "userspace grant access device driver" 142 depends on XEN 143 default m 144 select MMU_NOTIFIER 145 help 146 Allows userspace processes to use grants. 147 148config XEN_GRANT_DEV_ALLOC 149 tristate "User-space grant reference allocator driver" 150 depends on XEN 151 default m 152 help 153 Allows userspace processes to create pages with access granted 154 to other domains. This can be used to implement frontend drivers 155 or as part of an inter-domain shared memory channel. 156 157config SWIOTLB_XEN 158 def_bool y 159 select SWIOTLB 160 161config XEN_TMEM 162 tristate 163 depends on !ARM && !ARM64 164 default m if (CLEANCACHE || FRONTSWAP) 165 help 166 Shim to interface in-kernel Transcendent Memory hooks 167 (e.g. cleancache and frontswap) to Xen tmem hypercalls. 168 169config XEN_PCIDEV_BACKEND 170 tristate "Xen PCI-device backend driver" 171 depends on PCI && X86 && XEN 172 depends on XEN_BACKEND 173 default m 174 help 175 The PCI device backend driver allows the kernel to export arbitrary 176 PCI devices to other guests. If you select this to be a module, you 177 will need to make sure no other driver has bound to the device(s) 178 you want to make visible to other guests. 179 180 The parameter "passthrough" allows you specify how you want the PCI 181 devices to appear in the guest. You can choose the default (0) where 182 PCI topology starts at 00.00.0, or (1) for passthrough if you want 183 the PCI devices topology appear the same as in the host. 184 185 The "hide" parameter (only applicable if backend driver is compiled 186 into the kernel) allows you to bind the PCI devices to this module 187 from the default device drivers. The argument is the list of PCI BDFs: 188 xen-pciback.hide=(03:00.0)(04:00.0) 189 190 If in doubt, say m. 191 192config XEN_SCSI_BACKEND 193 tristate "XEN SCSI backend driver" 194 depends on XEN && XEN_BACKEND && TARGET_CORE 195 help 196 The SCSI backend driver allows the kernel to export its SCSI Devices 197 to other guests via a high-performance shared-memory interface. 198 Only needed for systems running as XEN driver domains (e.g. Dom0) and 199 if guests need generic access to SCSI devices. 200 201config XEN_PRIVCMD 202 tristate 203 depends on XEN 204 default m 205 206config XEN_STUB 207 bool "Xen stub drivers" 208 depends on XEN && X86_64 && BROKEN 209 default n 210 help 211 Allow kernel to install stub drivers, to reserve space for Xen drivers, 212 i.e. memory hotplug and cpu hotplug, and to block native drivers loaded, 213 so that real Xen drivers can be modular. 214 215 To enable Xen features like cpu and memory hotplug, select Y here. 216 217config XEN_ACPI_HOTPLUG_MEMORY 218 tristate "Xen ACPI memory hotplug" 219 depends on XEN_DOM0 && XEN_STUB && ACPI 220 default n 221 help 222 This is Xen ACPI memory hotplug. 223 224 Currently Xen only support ACPI memory hot-add. If you want 225 to hot-add memory at runtime (the hot-added memory cannot be 226 removed until machine stop), select Y/M here, otherwise select N. 227 228config XEN_ACPI_HOTPLUG_CPU 229 tristate "Xen ACPI cpu hotplug" 230 depends on XEN_DOM0 && XEN_STUB && ACPI 231 select ACPI_CONTAINER 232 default n 233 help 234 Xen ACPI cpu enumerating and hotplugging 235 236 For hotplugging, currently Xen only support ACPI cpu hotadd. 237 If you want to hotadd cpu at runtime (the hotadded cpu cannot 238 be removed until machine stop), select Y/M here. 239 240config XEN_ACPI_PROCESSOR 241 tristate "Xen ACPI processor" 242 depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ 243 default m 244 help 245 This ACPI processor uploads Power Management information to the Xen 246 hypervisor. 247 248 To do that the driver parses the Power Management data and uploads 249 said information to the Xen hypervisor. Then the Xen hypervisor can 250 select the proper Cx and Pxx states. It also registers itself as the 251 SMM so that other drivers (such as ACPI cpufreq scaling driver) will 252 not load. 253 254 To compile this driver as a module, choose M here: the module will be 255 called xen_acpi_processor If you do not know what to choose, select 256 M here. If the CPUFREQ drivers are built in, select Y here. 257 258config XEN_MCE_LOG 259 bool "Xen platform mcelog" 260 depends on XEN_DOM0 && X86_64 && X86_MCE 261 default n 262 help 263 Allow kernel fetching MCE error from Xen platform and 264 converting it into Linux mcelog format for mcelog tools 265 266config XEN_HAVE_PVMMU 267 bool 268 269config XEN_EFI 270 def_bool y 271 depends on X86_64 && EFI 272 273config XEN_AUTO_XLATE 274 def_bool y 275 depends on ARM || ARM64 || XEN_PVHVM 276 help 277 Support for auto-translated physmap guests. 278 279config XEN_ACPI 280 def_bool y 281 depends on X86 && ACPI 282 283config XEN_SYMS 284 bool "Xen symbols" 285 depends on X86 && XEN_DOM0 && XENFS 286 default y if KALLSYMS 287 help 288 Exports hypervisor symbols (along with their types and addresses) via 289 /proc/xen/xensyms file, similar to /proc/kallsyms 290 291config XEN_HAVE_VPMU 292 bool 293 294endmenu 295