linux_dsm_epyc7002/arch/arm/kvm/Kconfig
Christoffer Dall d5d8184d35 KVM: ARM: Memory virtualization setup
This commit introduces the framework for guest memory management
through the use of 2nd stage translation. Each VM has a pointer
to a level-1 table (the pgd field in struct kvm_arch) which is
used for the 2nd stage translations. Entries are added when handling
guest faults (later patch) and the table itself can be allocated and
freed through the following functions implemented in
arch/arm/kvm/arm_mmu.c:
 - kvm_alloc_stage2_pgd(struct kvm *kvm);
 - kvm_free_stage2_pgd(struct kvm *kvm);

Each entry in TLBs and caches are tagged with a VMID identifier in
addition to ASIDs. The VMIDs are assigned consecutively to VMs in the
order that VMs are executed, and caches and tlbs are invalidated when
the VMID space has been used to allow for more than 255 simultaenously
running guests.

The 2nd stage pgd is allocated in kvm_arch_init_vm(). The table is
freed in kvm_arch_destroy_vm(). Both functions are called from the main
KVM code.

We pre-allocate page table memory to be able to synchronize using a
spinlock and be called under rcu_read_lock from the MMU notifiers.  We
steal the mmu_memory_cache implementation from x86 and adapt for our
specific usage.

We support MMU notifiers (thanks to Marc Zyngier) through
kvm_unmap_hva and kvm_set_spte_hva.

Finally, define kvm_phys_addr_ioremap() to map a device at a guest IPA,
which is used by VGIC support to map the virtual CPU interface registers
to the guest. This support is added by Marc Zyngier.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-23 13:29:11 -05:00

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#
# KVM configuration
#
source "virt/kvm/Kconfig"
menuconfig VIRTUALIZATION
bool "Virtualization"
---help---
Say Y here to get to see options for using your Linux host to run
other operating systems inside virtual machines (guests).
This option alone does not add any kernel code.
If you say N, all options in this submenu will be skipped and
disabled.
if VIRTUALIZATION
config KVM
bool "Kernel-based Virtual Machine (KVM) support"
select PREEMPT_NOTIFIERS
select ANON_INODES
select KVM_MMIO
select KVM_ARM_HOST
depends on ARM_VIRT_EXT && ARM_LPAE
---help---
Support hosting virtualized guest machines. You will also
need to select one or more of the processor modules below.
This module provides access to the hardware capabilities through
a character device node named /dev/kvm.
If unsure, say N.
config KVM_ARM_HOST
bool "KVM host support for ARM cpus."
depends on KVM
depends on MMU
select MMU_NOTIFIER
---help---
Provides host support for ARM processors.
config KVM_ARM_MAX_VCPUS
int "Number maximum supported virtual CPUs per VM"
depends on KVM_ARM_HOST
default 4
help
Static number of max supported virtual CPUs per VM.
If you choose a high number, the vcpu structures will be quite
large, so only choose a reasonable number that you expect to
actually use.
source drivers/virtio/Kconfig
endif # VIRTUALIZATION