| 1 | menu "Xen driver support" |
| 2 | depends on XEN |
| 3 | |
| 4 | config 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 | |
| 12 | config 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 but can be enabled with the |
| 22 | 'selfballooning' kernel boot parameter. If FRONTSWAP is configured, |
| 23 | frontswap-selfshrinking is enabled by default but can be disabled |
| 24 | with the 'noselfshrink' kernel boot parameter; and self-ballooning |
| 25 | is enabled by default but can be disabled with the 'noselfballooning' |
| 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 triger 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 | default y |
| 90 | help |
| 91 | The xen filesystem provides a way for domains to share |
| 92 | information with each other and with the hypervisor. |
| 93 | For example, by reading and writing the "xenbus" file, guests |
| 94 | may pass arbitrary information to the initial domain. |
| 95 | If in doubt, say yes. |
| 96 | |
| 97 | config XEN_COMPAT_XENFS |
| 98 | bool "Create compatibility mount point /proc/xen" |
| 99 | depends on XENFS |
| 100 | default y |
| 101 | help |
| 102 | The old xenstore userspace tools expect to find "xenbus" |
| 103 | under /proc/xen, but "xenbus" is now found at the root of the |
| 104 | xenfs filesystem. Selecting this causes the kernel to create |
| 105 | the compatibility mount point /proc/xen if it is running on |
| 106 | a xen platform. |
| 107 | If in doubt, say yes. |
| 108 | |
| 109 | config XEN_SYS_HYPERVISOR |
| 110 | bool "Create xen entries under /sys/hypervisor" |
| 111 | depends on SYSFS |
| 112 | select SYS_HYPERVISOR |
| 113 | default y |
| 114 | help |
| 115 | Create entries under /sys/hypervisor describing the Xen |
| 116 | hypervisor environment. When running native or in another |
| 117 | virtual environment, /sys/hypervisor will still be present, |
| 118 | but will have no xen contents. |
| 119 | |
| 120 | config XEN_XENBUS_FRONTEND |
| 121 | tristate |
| 122 | |
| 123 | config XEN_GNTDEV |
| 124 | tristate "userspace grant access device driver" |
| 125 | depends on XEN |
| 126 | default m |
| 127 | select MMU_NOTIFIER |
| 128 | help |
| 129 | Allows userspace processes to use grants. |
| 130 | |
| 131 | config XEN_GRANT_DEV_ALLOC |
| 132 | tristate "User-space grant reference allocator driver" |
| 133 | depends on XEN |
| 134 | default m |
| 135 | help |
| 136 | Allows userspace processes to create pages with access granted |
| 137 | to other domains. This can be used to implement frontend drivers |
| 138 | or as part of an inter-domain shared memory channel. |
| 139 | |
| 140 | config SWIOTLB_XEN |
| 141 | def_bool y |
| 142 | depends on PCI |
| 143 | select SWIOTLB |
| 144 | |
| 145 | config XEN_TMEM |
| 146 | bool |
| 147 | default y if (CLEANCACHE || FRONTSWAP) |
| 148 | help |
| 149 | Shim to interface in-kernel Transcendent Memory hooks |
| 150 | (e.g. cleancache and frontswap) to Xen tmem hypercalls. |
| 151 | |
| 152 | config XEN_PCIDEV_BACKEND |
| 153 | tristate "Xen PCI-device backend driver" |
| 154 | depends on PCI && X86 && XEN |
| 155 | depends on XEN_BACKEND |
| 156 | default m |
| 157 | help |
| 158 | The PCI device backend driver allows the kernel to export arbitrary |
| 159 | PCI devices to other guests. If you select this to be a module, you |
| 160 | will need to make sure no other driver has bound to the device(s) |
| 161 | you want to make visible to other guests. |
| 162 | |
| 163 | The parameter "passthrough" allows you specify how you want the PCI |
| 164 | devices to appear in the guest. You can choose the default (0) where |
| 165 | PCI topology starts at 00.00.0, or (1) for passthrough if you want |
| 166 | the PCI devices topology appear the same as in the host. |
| 167 | |
| 168 | The "hide" parameter (only applicable if backend driver is compiled |
| 169 | into the kernel) allows you to bind the PCI devices to this module |
| 170 | from the default device drivers. The argument is the list of PCI BDFs: |
| 171 | xen-pciback.hide=(03:00.0)(04:00.0) |
| 172 | |
| 173 | If in doubt, say m. |
| 174 | endmenu |