WSL2-Linux-Kernel/arch/riscv/kvm/tlb.c

462 строки
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2022 Ventana Micro Systems Inc.
*/
#include <linux/bitmap.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/smp.h>
#include <linux/kvm_host.h>
#include <asm/cacheflush.h>
#include <asm/csr.h>
/*
* Instruction encoding of hfence.gvma is:
* HFENCE.GVMA rs1, rs2
* HFENCE.GVMA zero, rs2
* HFENCE.GVMA rs1
* HFENCE.GVMA
*
* rs1!=zero and rs2!=zero ==> HFENCE.GVMA rs1, rs2
* rs1==zero and rs2!=zero ==> HFENCE.GVMA zero, rs2
* rs1!=zero and rs2==zero ==> HFENCE.GVMA rs1
* rs1==zero and rs2==zero ==> HFENCE.GVMA
*
* Instruction encoding of HFENCE.GVMA is:
* 0110001 rs2(5) rs1(5) 000 00000 1110011
*/
void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid,
gpa_t gpa, gpa_t gpsz,
unsigned long order)
{
gpa_t pos;
if (PTRS_PER_PTE < (gpsz >> order)) {
kvm_riscv_local_hfence_gvma_vmid_all(vmid);
return;
}
for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) {
/*
* rs1 = a0 (GPA >> 2)
* rs2 = a1 (VMID)
* HFENCE.GVMA a0, a1
* 0110001 01011 01010 000 00000 1110011
*/
asm volatile ("srli a0, %0, 2\n"
"add a1, %1, zero\n"
".word 0x62b50073\n"
:: "r" (pos), "r" (vmid)
: "a0", "a1", "memory");
}
}
void kvm_riscv_local_hfence_gvma_vmid_all(unsigned long vmid)
{
/*
* rs1 = zero
* rs2 = a0 (VMID)
* HFENCE.GVMA zero, a0
* 0110001 01010 00000 000 00000 1110011
*/
asm volatile ("add a0, %0, zero\n"
".word 0x62a00073\n"
:: "r" (vmid) : "a0", "memory");
}
void kvm_riscv_local_hfence_gvma_gpa(gpa_t gpa, gpa_t gpsz,
unsigned long order)
{
gpa_t pos;
if (PTRS_PER_PTE < (gpsz >> order)) {
kvm_riscv_local_hfence_gvma_all();
return;
}
for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) {
/*
* rs1 = a0 (GPA >> 2)
* rs2 = zero
* HFENCE.GVMA a0
* 0110001 00000 01010 000 00000 1110011
*/
asm volatile ("srli a0, %0, 2\n"
".word 0x62050073\n"
:: "r" (pos) : "a0", "memory");
}
}
void kvm_riscv_local_hfence_gvma_all(void)
{
/*
* rs1 = zero
* rs2 = zero
* HFENCE.GVMA
* 0110001 00000 00000 000 00000 1110011
*/
asm volatile (".word 0x62000073" ::: "memory");
}
/*
* Instruction encoding of hfence.gvma is:
* HFENCE.VVMA rs1, rs2
* HFENCE.VVMA zero, rs2
* HFENCE.VVMA rs1
* HFENCE.VVMA
*
* rs1!=zero and rs2!=zero ==> HFENCE.VVMA rs1, rs2
* rs1==zero and rs2!=zero ==> HFENCE.VVMA zero, rs2
* rs1!=zero and rs2==zero ==> HFENCE.VVMA rs1
* rs1==zero and rs2==zero ==> HFENCE.VVMA
*
* Instruction encoding of HFENCE.VVMA is:
* 0010001 rs2(5) rs1(5) 000 00000 1110011
*/
void kvm_riscv_local_hfence_vvma_asid_gva(unsigned long vmid,
unsigned long asid,
unsigned long gva,
unsigned long gvsz,
unsigned long order)
{
unsigned long pos, hgatp;
if (PTRS_PER_PTE < (gvsz >> order)) {
kvm_riscv_local_hfence_vvma_asid_all(vmid, asid);
return;
}
hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) {
/*
* rs1 = a0 (GVA)
* rs2 = a1 (ASID)
* HFENCE.VVMA a0, a1
* 0010001 01011 01010 000 00000 1110011
*/
asm volatile ("add a0, %0, zero\n"
"add a1, %1, zero\n"
".word 0x22b50073\n"
:: "r" (pos), "r" (asid)
: "a0", "a1", "memory");
}
csr_write(CSR_HGATP, hgatp);
}
void kvm_riscv_local_hfence_vvma_asid_all(unsigned long vmid,
unsigned long asid)
{
unsigned long hgatp;
hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
/*
* rs1 = zero
* rs2 = a0 (ASID)
* HFENCE.VVMA zero, a0
* 0010001 01010 00000 000 00000 1110011
*/
asm volatile ("add a0, %0, zero\n"
".word 0x22a00073\n"
:: "r" (asid) : "a0", "memory");
csr_write(CSR_HGATP, hgatp);
}
void kvm_riscv_local_hfence_vvma_gva(unsigned long vmid,
unsigned long gva, unsigned long gvsz,
unsigned long order)
{
unsigned long pos, hgatp;
if (PTRS_PER_PTE < (gvsz >> order)) {
kvm_riscv_local_hfence_vvma_all(vmid);
return;
}
hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) {
/*
* rs1 = a0 (GVA)
* rs2 = zero
* HFENCE.VVMA a0
* 0010001 00000 01010 000 00000 1110011
*/
asm volatile ("add a0, %0, zero\n"
".word 0x22050073\n"
:: "r" (pos) : "a0", "memory");
}
csr_write(CSR_HGATP, hgatp);
}
void kvm_riscv_local_hfence_vvma_all(unsigned long vmid)
{
unsigned long hgatp;
hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT);
/*
* rs1 = zero
* rs2 = zero
* HFENCE.VVMA
* 0010001 00000 00000 000 00000 1110011
*/
asm volatile (".word 0x22000073" ::: "memory");
csr_write(CSR_HGATP, hgatp);
}
void kvm_riscv_local_tlb_sanitize(struct kvm_vcpu *vcpu)
{
unsigned long vmid;
if (!kvm_riscv_gstage_vmid_bits() ||
vcpu->arch.last_exit_cpu == vcpu->cpu)
return;
/*
* On RISC-V platforms with hardware VMID support, we share same
* VMID for all VCPUs of a particular Guest/VM. This means we might
* have stale G-stage TLB entries on the current Host CPU due to
* some other VCPU of the same Guest which ran previously on the
* current Host CPU.
*
* To cleanup stale TLB entries, we simply flush all G-stage TLB
* entries by VMID whenever underlying Host CPU changes for a VCPU.
*/
vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid);
kvm_riscv_local_hfence_gvma_vmid_all(vmid);
}
void kvm_riscv_fence_i_process(struct kvm_vcpu *vcpu)
{
local_flush_icache_all();
}
void kvm_riscv_hfence_gvma_vmid_all_process(struct kvm_vcpu *vcpu)
{
struct kvm_vmid *vmid;
vmid = &vcpu->kvm->arch.vmid;
kvm_riscv_local_hfence_gvma_vmid_all(READ_ONCE(vmid->vmid));
}
void kvm_riscv_hfence_vvma_all_process(struct kvm_vcpu *vcpu)
{
struct kvm_vmid *vmid;
vmid = &vcpu->kvm->arch.vmid;
kvm_riscv_local_hfence_vvma_all(READ_ONCE(vmid->vmid));
}
static bool vcpu_hfence_dequeue(struct kvm_vcpu *vcpu,
struct kvm_riscv_hfence *out_data)
{
bool ret = false;
struct kvm_vcpu_arch *varch = &vcpu->arch;
spin_lock(&varch->hfence_lock);
if (varch->hfence_queue[varch->hfence_head].type) {
memcpy(out_data, &varch->hfence_queue[varch->hfence_head],
sizeof(*out_data));
varch->hfence_queue[varch->hfence_head].type = 0;
varch->hfence_head++;
if (varch->hfence_head == KVM_RISCV_VCPU_MAX_HFENCE)
varch->hfence_head = 0;
ret = true;
}
spin_unlock(&varch->hfence_lock);
return ret;
}
static bool vcpu_hfence_enqueue(struct kvm_vcpu *vcpu,
const struct kvm_riscv_hfence *data)
{
bool ret = false;
struct kvm_vcpu_arch *varch = &vcpu->arch;
spin_lock(&varch->hfence_lock);
if (!varch->hfence_queue[varch->hfence_tail].type) {
memcpy(&varch->hfence_queue[varch->hfence_tail],
data, sizeof(*data));
varch->hfence_tail++;
if (varch->hfence_tail == KVM_RISCV_VCPU_MAX_HFENCE)
varch->hfence_tail = 0;
ret = true;
}
spin_unlock(&varch->hfence_lock);
return ret;
}
void kvm_riscv_hfence_process(struct kvm_vcpu *vcpu)
{
struct kvm_riscv_hfence d = { 0 };
struct kvm_vmid *v = &vcpu->kvm->arch.vmid;
while (vcpu_hfence_dequeue(vcpu, &d)) {
switch (d.type) {
case KVM_RISCV_HFENCE_UNKNOWN:
break;
case KVM_RISCV_HFENCE_GVMA_VMID_GPA:
kvm_riscv_local_hfence_gvma_vmid_gpa(
READ_ONCE(v->vmid),
d.addr, d.size, d.order);
break;
case KVM_RISCV_HFENCE_VVMA_ASID_GVA:
kvm_riscv_local_hfence_vvma_asid_gva(
READ_ONCE(v->vmid), d.asid,
d.addr, d.size, d.order);
break;
case KVM_RISCV_HFENCE_VVMA_ASID_ALL:
kvm_riscv_local_hfence_vvma_asid_all(
READ_ONCE(v->vmid), d.asid);
break;
case KVM_RISCV_HFENCE_VVMA_GVA:
kvm_riscv_local_hfence_vvma_gva(
READ_ONCE(v->vmid),
d.addr, d.size, d.order);
break;
default:
break;
}
}
}
static void make_xfence_request(struct kvm *kvm,
unsigned long hbase, unsigned long hmask,
unsigned int req, unsigned int fallback_req,
const struct kvm_riscv_hfence *data)
{
unsigned long i;
struct kvm_vcpu *vcpu;
unsigned int actual_req = req;
DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
bitmap_clear(vcpu_mask, 0, KVM_MAX_VCPUS);
kvm_for_each_vcpu(i, vcpu, kvm) {
if (hbase != -1UL) {
if (vcpu->vcpu_id < hbase)
continue;
if (!(hmask & (1UL << (vcpu->vcpu_id - hbase))))
continue;
}
bitmap_set(vcpu_mask, i, 1);
if (!data || !data->type)
continue;
/*
* Enqueue hfence data to VCPU hfence queue. If we don't
* have space in the VCPU hfence queue then fallback to
* a more conservative hfence request.
*/
if (!vcpu_hfence_enqueue(vcpu, data))
actual_req = fallback_req;
}
kvm_make_vcpus_request_mask(kvm, actual_req, vcpu_mask);
}
void kvm_riscv_fence_i(struct kvm *kvm,
unsigned long hbase, unsigned long hmask)
{
make_xfence_request(kvm, hbase, hmask, KVM_REQ_FENCE_I,
KVM_REQ_FENCE_I, NULL);
}
void kvm_riscv_hfence_gvma_vmid_gpa(struct kvm *kvm,
unsigned long hbase, unsigned long hmask,
gpa_t gpa, gpa_t gpsz,
unsigned long order)
{
struct kvm_riscv_hfence data;
data.type = KVM_RISCV_HFENCE_GVMA_VMID_GPA;
data.asid = 0;
data.addr = gpa;
data.size = gpsz;
data.order = order;
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
KVM_REQ_HFENCE_GVMA_VMID_ALL, &data);
}
void kvm_riscv_hfence_gvma_vmid_all(struct kvm *kvm,
unsigned long hbase, unsigned long hmask)
{
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_GVMA_VMID_ALL,
KVM_REQ_HFENCE_GVMA_VMID_ALL, NULL);
}
void kvm_riscv_hfence_vvma_asid_gva(struct kvm *kvm,
unsigned long hbase, unsigned long hmask,
unsigned long gva, unsigned long gvsz,
unsigned long order, unsigned long asid)
{
struct kvm_riscv_hfence data;
data.type = KVM_RISCV_HFENCE_VVMA_ASID_GVA;
data.asid = asid;
data.addr = gva;
data.size = gvsz;
data.order = order;
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
KVM_REQ_HFENCE_VVMA_ALL, &data);
}
void kvm_riscv_hfence_vvma_asid_all(struct kvm *kvm,
unsigned long hbase, unsigned long hmask,
unsigned long asid)
{
struct kvm_riscv_hfence data;
data.type = KVM_RISCV_HFENCE_VVMA_ASID_ALL;
data.asid = asid;
data.addr = data.size = data.order = 0;
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
KVM_REQ_HFENCE_VVMA_ALL, &data);
}
void kvm_riscv_hfence_vvma_gva(struct kvm *kvm,
unsigned long hbase, unsigned long hmask,
unsigned long gva, unsigned long gvsz,
unsigned long order)
{
struct kvm_riscv_hfence data;
data.type = KVM_RISCV_HFENCE_VVMA_GVA;
data.asid = 0;
data.addr = gva;
data.size = gvsz;
data.order = order;
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE,
KVM_REQ_HFENCE_VVMA_ALL, &data);
}
void kvm_riscv_hfence_vvma_all(struct kvm *kvm,
unsigned long hbase, unsigned long hmask)
{
make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_VVMA_ALL,
KVM_REQ_HFENCE_VVMA_ALL, NULL);
}