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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 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
29config 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
59config 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
70config 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
79config 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
87config 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
97config 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
109config 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
120config XEN_XENBUS_FRONTEND
121 tristate
122
123config 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
131config 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
140config XEN_PLATFORM_PCI
141 tristate "xen platform pci device driver"
142 depends on XEN_PVHVM && PCI
143 default m
144 help
145 Driver for the Xen PCI Platform device: it is responsible for
146 initializing xenbus and grant_table when running in a Xen HVM
147 domain. As a consequence this driver is required to run any Xen PV
148 frontend on Xen HVM.
149
150config SWIOTLB_XEN
151 def_bool y
152 depends on PCI
153 select SWIOTLB
154
155config XEN_TMEM
156 bool
157 default y if (CLEANCACHE || FRONTSWAP)
158 help
159 Shim to interface in-kernel Transcendent Memory hooks
160 (e.g. cleancache and frontswap) to Xen tmem hypercalls.
161
162config XEN_PCIDEV_BACKEND
163 tristate "Xen PCI-device backend driver"
164 depends on PCI && X86 && XEN
165 depends on XEN_BACKEND
166 default m
167 help
168 The PCI device backend driver allows the kernel to export arbitrary
169 PCI devices to other guests. If you select this to be a module, you
170 will need to make sure no other driver has bound to the device(s)
171 you want to make visible to other guests.
172
173 The parameter "passthrough" allows you specify how you want the PCI
174 devices to appear in the guest. You can choose the default (0) where
175 PCI topology starts at 00.00.0, or (1) for passthrough if you want
176 the PCI devices topology appear the same as in the host.
177
178 The "hide" parameter (only applicable if backend driver is compiled
179 into the kernel) allows you to bind the PCI devices to this module
180 from the default device drivers. The argument is the list of PCI BDFs:
181 xen-pciback.hide=(03:00.0)(04:00.0)
182
183 If in doubt, say m.
184endmenu
1# SPDX-License-Identifier: GPL-2.0-only
2menu "Xen driver support"
3 depends on XEN
4
5config XEN_BALLOON
6 bool "Xen memory balloon driver"
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
13config XEN_BALLOON_MEMORY_HOTPLUG
14 bool "Memory hotplug support for Xen balloon driver"
15 depends on XEN_BALLOON && MEMORY_HOTPLUG
16 default y
17 help
18 Memory hotplug support for Xen balloon driver allows expanding memory
19 available for the system above limit declared at system startup.
20 It is very useful on critical systems which require long
21 run without rebooting.
22
23 It's also very useful for non PV domains to obtain unpopulated physical
24 memory ranges to use in order to map foreign memory or grants.
25
26 Memory could be hotplugged in following steps:
27
28 1) target domain: ensure that memory auto online policy is in
29 effect by checking /sys/devices/system/memory/auto_online_blocks
30 file (should be 'online').
31
32 2) control domain: xl mem-max <target-domain> <maxmem>
33 where <maxmem> is >= requested memory size,
34
35 3) control domain: xl mem-set <target-domain> <memory>
36 where <memory> is requested memory size; alternatively memory
37 could be added by writing proper value to
38 /sys/devices/system/xen_memory/xen_memory0/target or
39 /sys/devices/system/xen_memory/xen_memory0/target_kb on the
40 target domain.
41
42 Alternatively, if memory auto onlining was not requested at step 1
43 the newly added memory can be manually onlined in the target domain
44 by doing the following:
45
46 for i in /sys/devices/system/memory/memory*/state; do \
47 [ "`cat "$i"`" = offline ] && echo online > "$i"; done
48
49 or by adding the following line to udev rules:
50
51 SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"
52
53config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT
54 int "Hotplugged memory limit (in GiB) for a PV guest"
55 default 512
56 depends on XEN_HAVE_PVMMU
57 depends on XEN_BALLOON_MEMORY_HOTPLUG
58 help
59 Maxmium amount of memory (in GiB) that a PV guest can be
60 expanded to when using memory hotplug.
61
62 A PV guest can have more memory than this limit if is
63 started with a larger maximum.
64
65 This value is used to allocate enough space in internal
66 tables needed for physical memory administration.
67
68config XEN_SCRUB_PAGES_DEFAULT
69 bool "Scrub pages before returning them to system by default"
70 depends on XEN_BALLOON
71 default y
72 help
73 Scrub pages before returning them to the system for reuse by
74 other domains. This makes sure that any confidential data
75 is not accidentally visible to other domains. It is more
76 secure, but slightly less efficient. This can be controlled with
77 xen_scrub_pages=0 parameter and
78 /sys/devices/system/xen_memory/xen_memory0/scrub_pages.
79 This option only sets the default value.
80
81 If in doubt, say yes.
82
83config XEN_DEV_EVTCHN
84 tristate "Xen /dev/xen/evtchn device"
85 default y
86 help
87 The evtchn driver allows a userspace process to trigger event
88 channels and to receive notification of an event channel
89 firing.
90 If in doubt, say yes.
91
92config XEN_BACKEND
93 bool "Backend driver support"
94 default XEN_DOM0
95 help
96 Support for backend device drivers that provide I/O services
97 to other virtual machines.
98
99config XENFS
100 tristate "Xen filesystem"
101 select XEN_PRIVCMD
102 default y
103 help
104 The xen filesystem provides a way for domains to share
105 information with each other and with the hypervisor.
106 For example, by reading and writing the "xenbus" file, guests
107 may pass arbitrary information to the initial domain.
108 If in doubt, say yes.
109
110config XEN_COMPAT_XENFS
111 bool "Create compatibility mount point /proc/xen"
112 depends on XENFS
113 default y
114 help
115 The old xenstore userspace tools expect to find "xenbus"
116 under /proc/xen, but "xenbus" is now found at the root of the
117 xenfs filesystem. Selecting this causes the kernel to create
118 the compatibility mount point /proc/xen if it is running on
119 a xen platform.
120 If in doubt, say yes.
121
122config XEN_SYS_HYPERVISOR
123 bool "Create xen entries under /sys/hypervisor"
124 depends on SYSFS
125 select SYS_HYPERVISOR
126 default y
127 help
128 Create entries under /sys/hypervisor describing the Xen
129 hypervisor environment. When running native or in another
130 virtual environment, /sys/hypervisor will still be present,
131 but will have no xen contents.
132
133config XEN_XENBUS_FRONTEND
134 tristate
135
136config XEN_GNTDEV
137 tristate "userspace grant access device driver"
138 depends on XEN
139 default m
140 select MMU_NOTIFIER
141 help
142 Allows userspace processes to use grants.
143
144config XEN_GNTDEV_DMABUF
145 bool "Add support for dma-buf grant access device driver extension"
146 depends on XEN_GNTDEV && XEN_GRANT_DMA_ALLOC
147 select DMA_SHARED_BUFFER
148 help
149 Allows userspace processes and kernel modules to use Xen backed
150 dma-buf implementation. With this extension grant references to
151 the pages of an imported dma-buf can be exported for other domain
152 use and grant references coming from a foreign domain can be
153 converted into a local dma-buf for local export.
154
155config XEN_GRANT_DEV_ALLOC
156 tristate "User-space grant reference allocator driver"
157 depends on XEN
158 default m
159 help
160 Allows userspace processes to create pages with access granted
161 to other domains. This can be used to implement frontend drivers
162 or as part of an inter-domain shared memory channel.
163
164config XEN_GRANT_DMA_ALLOC
165 bool "Allow allocating DMA capable buffers with grant reference module"
166 depends on XEN && HAS_DMA
167 help
168 Extends grant table module API to allow allocating DMA capable
169 buffers and mapping foreign grant references on top of it.
170 The resulting buffer is similar to one allocated by the balloon
171 driver in that proper memory reservation is made by
172 ({increase|decrease}_reservation and VA mappings are updated if
173 needed).
174 This is useful for sharing foreign buffers with HW drivers which
175 cannot work with scattered buffers provided by the balloon driver,
176 but require DMAable memory instead.
177
178config SWIOTLB_XEN
179 def_bool y
180 select DMA_OPS
181 select SWIOTLB
182
183config XEN_PCIDEV_BACKEND
184 tristate "Xen PCI-device backend driver"
185 depends on PCI && X86 && XEN
186 depends on XEN_BACKEND
187 default m
188 help
189 The PCI device backend driver allows the kernel to export arbitrary
190 PCI devices to other guests. If you select this to be a module, you
191 will need to make sure no other driver has bound to the device(s)
192 you want to make visible to other guests.
193
194 The parameter "passthrough" allows you specify how you want the PCI
195 devices to appear in the guest. You can choose the default (0) where
196 PCI topology starts at 00.00.0, or (1) for passthrough if you want
197 the PCI devices topology appear the same as in the host.
198
199 The "hide" parameter (only applicable if backend driver is compiled
200 into the kernel) allows you to bind the PCI devices to this module
201 from the default device drivers. The argument is the list of PCI BDFs:
202 xen-pciback.hide=(03:00.0)(04:00.0)
203
204 If in doubt, say m.
205
206config XEN_PVCALLS_FRONTEND
207 tristate "XEN PV Calls frontend driver"
208 depends on INET && XEN
209 select XEN_XENBUS_FRONTEND
210 help
211 Experimental frontend for the Xen PV Calls protocol
212 (https://xenbits.xen.org/docs/unstable/misc/pvcalls.html). It
213 sends a small set of POSIX calls to the backend, which
214 implements them.
215
216config XEN_PVCALLS_BACKEND
217 bool "XEN PV Calls backend driver"
218 depends on INET && XEN && XEN_BACKEND
219 help
220 Experimental backend for the Xen PV Calls protocol
221 (https://xenbits.xen.org/docs/unstable/misc/pvcalls.html). It
222 allows PV Calls frontends to send POSIX calls to the backend,
223 which implements them.
224
225 If in doubt, say n.
226
227config XEN_SCSI_BACKEND
228 tristate "XEN SCSI backend driver"
229 depends on XEN && XEN_BACKEND && TARGET_CORE
230 help
231 The SCSI backend driver allows the kernel to export its SCSI Devices
232 to other guests via a high-performance shared-memory interface.
233 Only needed for systems running as XEN driver domains (e.g. Dom0) and
234 if guests need generic access to SCSI devices.
235
236config XEN_PRIVCMD
237 tristate
238 depends on XEN
239 default m
240
241config XEN_STUB
242 bool "Xen stub drivers"
243 depends on XEN && X86_64 && BROKEN
244 help
245 Allow kernel to install stub drivers, to reserve space for Xen drivers,
246 i.e. memory hotplug and cpu hotplug, and to block native drivers loaded,
247 so that real Xen drivers can be modular.
248
249 To enable Xen features like cpu and memory hotplug, select Y here.
250
251config XEN_ACPI_HOTPLUG_MEMORY
252 tristate "Xen ACPI memory hotplug"
253 depends on XEN_DOM0 && XEN_STUB && ACPI
254 help
255 This is Xen ACPI memory hotplug.
256
257 Currently Xen only support ACPI memory hot-add. If you want
258 to hot-add memory at runtime (the hot-added memory cannot be
259 removed until machine stop), select Y/M here, otherwise select N.
260
261config XEN_ACPI_HOTPLUG_CPU
262 tristate "Xen ACPI cpu hotplug"
263 depends on XEN_DOM0 && XEN_STUB && ACPI
264 select ACPI_CONTAINER
265 help
266 Xen ACPI cpu enumerating and hotplugging
267
268 For hotplugging, currently Xen only support ACPI cpu hotadd.
269 If you want to hotadd cpu at runtime (the hotadded cpu cannot
270 be removed until machine stop), select Y/M here.
271
272config XEN_ACPI_PROCESSOR
273 tristate "Xen ACPI processor"
274 depends on XEN && XEN_DOM0 && X86 && ACPI_PROCESSOR && CPU_FREQ
275 default m
276 help
277 This ACPI processor uploads Power Management information to the Xen
278 hypervisor.
279
280 To do that the driver parses the Power Management data and uploads
281 said information to the Xen hypervisor. Then the Xen hypervisor can
282 select the proper Cx and Pxx states. It also registers itself as the
283 SMM so that other drivers (such as ACPI cpufreq scaling driver) will
284 not load.
285
286 To compile this driver as a module, choose M here: the module will be
287 called xen_acpi_processor If you do not know what to choose, select
288 M here. If the CPUFREQ drivers are built in, select Y here.
289
290config XEN_MCE_LOG
291 bool "Xen platform mcelog"
292 depends on XEN_DOM0 && X86_MCE
293 help
294 Allow kernel fetching MCE error from Xen platform and
295 converting it into Linux mcelog format for mcelog tools
296
297config XEN_HAVE_PVMMU
298 bool
299
300config XEN_EFI
301 def_bool y
302 depends on (ARM || ARM64 || X86_64) && EFI
303
304config XEN_AUTO_XLATE
305 def_bool y
306 depends on ARM || ARM64 || XEN_PVHVM
307 help
308 Support for auto-translated physmap guests.
309
310config XEN_ACPI
311 def_bool y
312 depends on X86 && ACPI
313
314config XEN_SYMS
315 bool "Xen symbols"
316 depends on X86 && XEN_DOM0 && XENFS
317 default y if KALLSYMS
318 help
319 Exports hypervisor symbols (along with their types and addresses) via
320 /proc/xen/xensyms file, similar to /proc/kallsyms
321
322config XEN_HAVE_VPMU
323 bool
324
325config XEN_FRONT_PGDIR_SHBUF
326 tristate
327
328config XEN_UNPOPULATED_ALLOC
329 bool "Use unpopulated memory ranges for guest mappings"
330 depends on X86 && ZONE_DEVICE
331 default XEN_BACKEND || XEN_GNTDEV || XEN_DOM0
332 help
333 Use unpopulated memory ranges in order to create mappings for guest
334 memory regions, including grant maps and foreign pages. This avoids
335 having to balloon out RAM regions in order to obtain physical memory
336 space to create such mappings.
337
338endmenu