kernel_optimize_test/arch/arm/kvm/hyp/tlb.c
Christoffer Dall e329fb75d5 KVM: arm/arm64: Factor out VMID into struct kvm_vmid
In preparation for nested virtualization where we are going to have more
than a single VMID per VM, let's factor out the VMID data into a
separate VMID data structure and change the VMID allocator to operate on
this new structure instead of using a struct kvm.

This also means that udate_vttbr now becomes update_vmid, and that the
vttbr itself is generated on the fly based on the stage 2 page table
base address and the vmid.

We cache the physical address of the pgd when allocating the pgd to
avoid doing the calculation on every entry to the guest and to avoid
calling into potentially non-hyp-mapped code from hyp/EL2.

If we wanted to merge the VMID allocator with the arm64 ASID allocator
at some point in the future, it should actually become easier to do that
after this patch.

Note that to avoid mapping the kvm_vmid_bits variable into hyp, we
simply forego the masking of the vmid value in kvm_get_vttbr and rely on
update_vmid to always assign a valid vmid value (within the supported
range).

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
[maz: minor cleanups]
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-19 21:05:35 +00:00

80 lines
2.1 KiB
C

/*
* Original code:
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
*
* Mostly rewritten in C by Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <asm/kvm_hyp.h>
#include <asm/kvm_mmu.h>
/**
* Flush per-VMID TLBs
*
* __kvm_tlb_flush_vmid(struct kvm *kvm);
*
* We rely on the hardware to broadcast the TLB invalidation to all CPUs
* inside the inner-shareable domain (which is the case for all v7
* implementations). If we come across a non-IS SMP implementation, we'll
* have to use an IPI based mechanism. Until then, we stick to the simple
* hardware assisted version.
*
* As v7 does not support flushing per IPA, just nuke the whole TLB
* instead, ignoring the ipa value.
*/
void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm)
{
dsb(ishst);
/* Switch to requested VMID */
kvm = kern_hyp_va(kvm);
write_sysreg(kvm_get_vttbr(kvm), VTTBR);
isb();
write_sysreg(0, TLBIALLIS);
dsb(ish);
isb();
write_sysreg(0, VTTBR);
}
void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
{
__kvm_tlb_flush_vmid(kvm);
}
void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = kern_hyp_va(kern_hyp_va(vcpu)->kvm);
/* Switch to requested VMID */
write_sysreg(kvm_get_vttbr(kvm), VTTBR);
isb();
write_sysreg(0, TLBIALL);
dsb(nsh);
isb();
write_sysreg(0, VTTBR);
}
void __hyp_text __kvm_flush_vm_context(void)
{
write_sysreg(0, TLBIALLNSNHIS);
write_sysreg(0, ICIALLUIS);
dsb(ish);
}