[PATCH v6 58/64] KVM: arm64: nv: Move nested vgic state into the sysreg file

Marc Zyngier
2022-01-28T12:49:59Z

The vgic nested state needs to be accessible from the VNCR page, and
thus needs to be part of the normal sysreg file. Let's move it there.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/include/asm/kvm_host.h | 9 +++
arch/arm64/kvm/sys_regs.c | 53 +++++++++++------
arch/arm64/kvm/vgic/vgic-v3-nested.c | 88 ++++++++++++++--------------
arch/arm64/kvm/vgic/vgic-v3.c | 17 ++++--
arch/arm64/kvm/vgic/vgic.h | 10 ++++
include/kvm/arm_vgic.h | 7 ---
6 files changed, 110 insertions(+), 74 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 3f6ddccae310..15bbe8ccdefa 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -311,6 +311,15 @@ enum vcpu_sysreg {
VNCR(CNTP_CVAL_EL0),
VNCR(CNTP_CTL_EL0),

+ VNCR(ICH_LR0_EL2),
+ ICH_LR15_EL2 = ICH_LR0_EL2 + 15,
+ VNCR(ICH_AP0R0_EL2),
+ ICH_AP0R3_EL2 = ICH_AP0R0_EL2 + 3,
+ VNCR(ICH_AP1R0_EL2),
+ ICH_AP1R3_EL2 = ICH_AP1R0_EL2 + 3,
+ VNCR(ICH_HCR_EL2),
+ VNCR(ICH_VMCR_EL2),
+
NR_SYS_REGS /* Nothing after this line! */
};

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 32b8f4c1074a..351bcb429f25 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1865,17 +1865,17 @@ static bool access_gic_apr(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.nested_vgic_v3;
- u32 index, *base;
+ u64 *base;
+ u8 index;

index = r->Op2;
if (r->CRm == 8)
- base = cpu_if->vgic_ap0r;
+ base = __ctxt_sys_reg(&vcpu->arch.ctxt, ICH_AP0R0_EL2);
else
- base = cpu_if->vgic_ap1r;
+ base = __ctxt_sys_reg(&vcpu->arch.ctxt, ICH_AP1R0_EL2);

if (p->is_write)
- base[index] = p->regval;
+ base[index] = lower_32_bits(p->regval);
else
p->regval = base[index];

@@ -1886,12 +1886,10 @@ static bool access_gic_hcr(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.nested_vgic_v3;
-
if (p->is_write)
- cpu_if->vgic_hcr = p->regval;
+ __vcpu_sys_reg(vcpu, ICH_HCR_EL2) = lower_32_bits(p->regval);
else
- p->regval = cpu_if->vgic_hcr;
+ p->regval = __vcpu_sys_reg(vcpu, ICH_HCR_EL2);

return true;
}
@@ -1948,12 +1946,19 @@ static bool access_gic_vmcr(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.nested_vgic_v3;
-
if (p->is_write)
- cpu_if->vgic_vmcr = p->regval;
+ __vcpu_sys_reg(vcpu, ICH_VMCR_EL2) = (p->regval &
+ (ICH_VMCR_ENG0_MASK |
+ ICH_VMCR_ENG1_MASK |
+ ICH_VMCR_PMR_MASK |
+ ICH_VMCR_BPR0_MASK |
+ ICH_VMCR_BPR1_MASK |
+ ICH_VMCR_EOIM_MASK |
+ ICH_VMCR_CBPR_MASK |
+ ICH_VMCR_FIQ_EN_MASK |
+ ICH_VMCR_ACK_CTL_MASK));
else
- p->regval = cpu_if->vgic_vmcr;
+ p->regval = __vcpu_sys_reg(vcpu, ICH_VMCR_EL2);

return true;
}
@@ -1962,17 +1967,29 @@ static bool access_gic_lr(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.nested_vgic_v3;
u32 index;
+ u64 *base;

+ base = __ctxt_sys_reg(&vcpu->arch.ctxt, ICH_LR0_EL2);
index = p->Op2;
if (p->CRm == 13)
index += 8;

- if (p->is_write)
- cpu_if->vgic_lr[index] = p->regval;
- else
- p->regval = cpu_if->vgic_lr[index];
+ if (p->is_write) {
+ u64 mask = (ICH_LR_VIRTUAL_ID_MASK |
+ ICH_LR_GROUP |
+ ICH_LR_HW |
+ ICH_LR_STATE);
+
+ if (p->regval & ICH_LR_HW)
+ mask |= ICH_LR_PHYS_ID_MASK;
+ else
+ mask |= ICH_LR_EOI;
+
+ base[index] = p->regval & mask;
+ } else {
+ p->regval = base[index];
+ }

return true;
}
diff --git a/arch/arm64/kvm/vgic/vgic-v3-nested.c b/arch/arm64/kvm/vgic/vgic-v3-nested.c
index 02b0b335f72a..5ffffddb5776 100644
--- a/arch/arm64/kvm/vgic/vgic-v3-nested.c
+++ b/arch/arm64/kvm/vgic/vgic-v3-nested.c
@@ -18,11 +18,6 @@
#define CREATE_TRACE_POINTS
#include "vgic-nested-trace.h"

-static inline struct vgic_v3_cpu_if *vcpu_nested_if(struct kvm_vcpu *vcpu)
-{
- return &vcpu->arch.vgic_cpu.nested_vgic_v3;
-}
-
static inline struct vgic_v3_cpu_if *vcpu_shadow_if(struct kvm_vcpu *vcpu)
{
return &vcpu->arch.vgic_cpu.shadow_vgic_v3;
@@ -35,12 +30,11 @@ static inline bool lr_triggers_eoi(u64 lr)

u16 vgic_v3_get_eisr(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
u16 reg = 0;
int i;

for (i = 0; i < kvm_vgic_global_state.nr_lr; i++) {
- if (lr_triggers_eoi(cpu_if->vgic_lr[i]))
+ if (lr_triggers_eoi(__vcpu_sys_reg(vcpu, ICH_LRN(i))))
reg |= BIT(i);
}

@@ -49,12 +43,11 @@ u16 vgic_v3_get_eisr(struct kvm_vcpu *vcpu)

u16 vgic_v3_get_elrsr(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
u16 reg = 0;
int i;

for (i = 0; i < kvm_vgic_global_state.nr_lr; i++) {
- if (!(cpu_if->vgic_lr[i] & ICH_LR_STATE))
+ if (!(__vcpu_sys_reg(vcpu, ICH_LRN(i)) & ICH_LR_STATE))
reg |= BIT(i);
}

@@ -63,14 +56,13 @@ u16 vgic_v3_get_elrsr(struct kvm_vcpu *vcpu)

u64 vgic_v3_get_misr(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
int nr_lr = kvm_vgic_global_state.nr_lr;
u64 reg = 0;

if (vgic_v3_get_eisr(vcpu))
reg |= ICH_MISR_EOI;

- if (cpu_if->vgic_hcr & ICH_HCR_UIE) {
+ if (__vcpu_sys_reg(vcpu, ICH_HCR_EL2) & ICH_HCR_UIE) {
int used_lrs;

used_lrs = nr_lr - hweight16(vgic_v3_get_elrsr(vcpu));
@@ -89,13 +81,12 @@ u64 vgic_v3_get_misr(struct kvm_vcpu *vcpu)
*/
static void vgic_v3_create_shadow_lr(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
struct vgic_v3_cpu_if *s_cpu_if = vcpu_shadow_if(vcpu);
struct vgic_irq *irq;
int i, used_lrs = 0;

for (i = 0; i < kvm_vgic_global_state.nr_lr; i++) {
- u64 lr = cpu_if->vgic_lr[i];
+ u64 lr = __vcpu_sys_reg(vcpu, ICH_LRN(i));
int l1_irq;

if (!(lr & ICH_LR_HW))
@@ -125,36 +116,20 @@ static void vgic_v3_create_shadow_lr(struct kvm_vcpu *vcpu)
}

trace_vgic_create_shadow_lrs(vcpu, kvm_vgic_global_state.nr_lr,
- s_cpu_if->vgic_lr, cpu_if->vgic_lr);
+ s_cpu_if->vgic_lr,
+ __ctxt_sys_reg(&vcpu->arch.ctxt, ICH_LR0_EL2));

s_cpu_if->used_lrs = used_lrs;
}

-/*
- * Change the shadow HWIRQ field back to the virtual value before copying over
- * the entire shadow struct to the nested state.
- */
-static void vgic_v3_fixup_shadow_lr_state(struct kvm_vcpu *vcpu)
-{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
- struct vgic_v3_cpu_if *s_cpu_if = vcpu_shadow_if(vcpu);
- int lr;
-
- for (lr = 0; lr < kvm_vgic_global_state.nr_lr; lr++) {
- s_cpu_if->vgic_lr[lr] &= ~ICH_LR_PHYS_ID_MASK;
- s_cpu_if->vgic_lr[lr] |= cpu_if->vgic_lr[lr] & ICH_LR_PHYS_ID_MASK;
- }
-}
-
void vgic_v3_sync_nested(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
struct vgic_v3_cpu_if *s_cpu_if = vcpu_shadow_if(vcpu);
struct vgic_irq *irq;
int i;

for (i = 0; i < s_cpu_if->used_lrs; i++) {
- u64 lr = cpu_if->vgic_lr[i];
+ u64 lr = __vcpu_sys_reg(vcpu, ICH_LRN(i));
int l1_irq;

if (!(lr & ICH_LR_HW) || !(lr & ICH_LR_STATE))
@@ -180,14 +155,27 @@ void vgic_v3_sync_nested(struct kvm_vcpu *vcpu)
}
}

+void vgic_v3_create_shadow_state(struct kvm_vcpu *vcpu)
+{
+ struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.shadow_vgic_v3;
+ int i;
+
+ cpu_if->vgic_hcr = __vcpu_sys_reg(vcpu, ICH_HCR_EL2);
+ cpu_if->vgic_vmcr = __vcpu_sys_reg(vcpu, ICH_VMCR_EL2);
+
+ for (i = 0; i < 4; i++) {
+ cpu_if->vgic_ap0r[i] = __vcpu_sys_reg(vcpu, ICH_AP0RN(i));
+ cpu_if->vgic_ap1r[i] = __vcpu_sys_reg(vcpu, ICH_AP1RN(i));
+ }
+
+ vgic_v3_create_shadow_lr(vcpu);
+}
+
void vgic_v3_load_nested(struct kvm_vcpu *vcpu)
{
- struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_irq *irq;
unsigned long flags;

- vgic_cpu->shadow_vgic_v3 = vgic_cpu->nested_vgic_v3;
- vgic_v3_create_shadow_lr(vcpu);
__vgic_v3_restore_state(vcpu_shadow_if(vcpu));

irq = vgic_get_irq(vcpu->kvm, vcpu, vcpu->kvm->arch.vgic.maint_irq);
@@ -201,26 +189,40 @@ void vgic_v3_load_nested(struct kvm_vcpu *vcpu)

void vgic_v3_put_nested(struct kvm_vcpu *vcpu)
{
- struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+ struct vgic_v3_cpu_if *s_cpu_if = vcpu_shadow_if(vcpu);
+ int i;

- __vgic_v3_save_state(vcpu_shadow_if(vcpu));
+ __vgic_v3_save_state(s_cpu_if);

- trace_vgic_put_nested(vcpu, kvm_vgic_global_state.nr_lr,
- vcpu_shadow_if(vcpu)->vgic_lr);
+ trace_vgic_put_nested(vcpu, kvm_vgic_global_state.nr_lr, s_cpu_if->vgic_lr);

/*
* Translate the shadow state HW fields back to the virtual ones
* before copying the shadow struct back to the nested one.
*/
- vgic_v3_fixup_shadow_lr_state(vcpu);
- vgic_cpu->nested_vgic_v3 = vgic_cpu->shadow_vgic_v3;
+ __vcpu_sys_reg(vcpu, ICH_HCR_EL2) = s_cpu_if->vgic_hcr;
+ __vcpu_sys_reg(vcpu, ICH_VMCR_EL2) = s_cpu_if->vgic_vmcr;
+
+ for (i = 0; i < 4; i++) {
+ __vcpu_sys_reg(vcpu, ICH_AP0RN(i)) = s_cpu_if->vgic_ap0r[i];
+ __vcpu_sys_reg(vcpu, ICH_AP1RN(i)) = s_cpu_if->vgic_ap1r[i];
+ }
+
+ for (i = 0; i < kvm_vgic_global_state.nr_lr; i++) {
+ u64 val = __vcpu_sys_reg(vcpu, ICH_LRN(i));
+
+ val &= ~ICH_LR_STATE;
+ val |= s_cpu_if->vgic_lr[i] & ICH_LR_STATE;
+
+ __vcpu_sys_reg(vcpu, ICH_LRN(i)) = val;
+ }
+
irq_set_irqchip_state(kvm_vgic_global_state.maint_irq,
IRQCHIP_STATE_ACTIVE, false);
}

void vgic_v3_handle_nested_maint_irq(struct kvm_vcpu *vcpu)
{
- struct vgic_v3_cpu_if *cpu_if = vcpu_nested_if(vcpu);
bool state;

/*
@@ -232,7 +234,7 @@ void vgic_v3_handle_nested_maint_irq(struct kvm_vcpu *vcpu)
if (!vgic_state_is_nested(vcpu))
return;

- state = cpu_if->vgic_hcr & ICH_HCR_EN;
+ state = __vcpu_sys_reg(vcpu, ICH_HCR_EL2) & ICH_HCR_EN;
state &= vgic_v3_get_misr(vcpu);

kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c
index 39e5c68087ea..f8ed60563587 100644
--- a/arch/arm64/kvm/vgic/vgic-v3.c
+++ b/arch/arm64/kvm/vgic/vgic-v3.c
@@ -280,10 +280,11 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu)
ICC_SRE_EL1_SRE);
/*
* If nesting is allowed, force GICv3 onto the nested
- * guests as well.
+ * guests as well by setting the shadow state to the
+ * same value.
*/
if (vcpu_has_nv(vcpu))
- vcpu->arch.vgic_cpu.nested_vgic_v3.vgic_sre = vgic_v3->vgic_sre;
+ vcpu->arch.vgic_cpu.shadow_vgic_v3.vgic_sre = vgic_v3->vgic_sre;
vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE;
} else {
vgic_v3->vgic_sre = 0;
@@ -715,11 +716,15 @@ void vgic_v3_load(struct kvm_vcpu *vcpu)
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;

/*
- * vgic_v3_load_nested only affects the LRs in the shadow
- * state, so it is fine to pass the nested state around.
+ * If the vgic is in nested state, populate the shadow state
+ * from the guest's nested state. As vgic_v3_load_nested()
+ * will only load LRs, let's deal with the rest of the state
+ * here as if it was a non-nested state. Cunning.
*/
- if (vgic_state_is_nested(vcpu))
- cpu_if = &vcpu->arch.vgic_cpu.nested_vgic_v3;
+ if (vgic_state_is_nested(vcpu)) {
+ vgic_v3_create_shadow_state(vcpu);
+ cpu_if = &vcpu->arch.vgic_cpu.shadow_vgic_v3;
+ }

/*
* If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
diff --git a/arch/arm64/kvm/vgic/vgic.h b/arch/arm64/kvm/vgic/vgic.h
index 3fd6c86a7ef3..ffdfe7bd9aea 100644
--- a/arch/arm64/kvm/vgic/vgic.h
+++ b/arch/arm64/kvm/vgic/vgic.h
@@ -323,4 +323,14 @@ void vgic_v4_teardown(struct kvm *kvm);
void vgic_v4_configure_vsgis(struct kvm *kvm);
void vgic_v4_get_vlpi_state(struct vgic_irq *irq, bool *val);

+void vgic_v3_sync_nested(struct kvm_vcpu *vcpu);
+void vgic_v3_create_shadow_state(struct kvm_vcpu *vcpu);
+void vgic_v3_load_nested(struct kvm_vcpu *vcpu);
+void vgic_v3_put_nested(struct kvm_vcpu *vcpu);
+void vgic_v3_handle_nested_maint_irq(struct kvm_vcpu *vcpu);
+
+#define ICH_LRN(n) (ICH_LR0_EL2 + (n))
+#define ICH_AP0RN(n) (ICH_AP0R0_EL2 + (n))
+#define ICH_AP1RN(n) (ICH_AP1R0_EL2 + (n))
+
#endif
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index b44db6b013f5..43fef20f1671 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -330,9 +330,6 @@ struct vgic_cpu {

struct vgic_irq private_irqs[VGIC_NR_PRIVATE_IRQS];

- /* CPU vif control registers for the virtual GICH interface */
- struct vgic_v3_cpu_if nested_vgic_v3;
-
/*
* The shadow vif control register loaded to the hardware when
* running a nested L2 guest with the virtual IMO/FMO bit set.
@@ -396,10 +393,6 @@ void kvm_vgic_load(struct kvm_vcpu *vcpu);
void kvm_vgic_put(struct kvm_vcpu *vcpu);
void kvm_vgic_vmcr_sync(struct kvm_vcpu *vcpu);

-void vgic_v3_sync_nested(struct kvm_vcpu *vcpu);
-void vgic_v3_load_nested(struct kvm_vcpu *vcpu);
-void vgic_v3_put_nested(struct kvm_vcpu *vcpu);
-void vgic_v3_handle_nested_maint_irq(struct kvm_vcpu *vcpu);
u16 vgic_v3_get_eisr(struct kvm_vcpu *vcpu);
u16 vgic_v3_get_elrsr(struct kvm_vcpu *vcpu);
u64 vgic_v3_get_misr(struct kvm_vcpu *vcpu);