KVM: arm/arm64: Move VGIC APR save/restore to vgic put/load

The APRs can only have bits set when the guest acknowledges an interrupt
in the LR and can only have a bit cleared when the guest EOIs an
interrupt in the LR.  Therefore, if we have no LRs with any
pending/active interrupts, the APR cannot change value and there is no
need to clear it on every exit from the VM (hint: it will have already
been cleared when we exited the guest the last time with the LRs all
EOIed).

The only case we need to take care of is when we migrate the VCPU away
from a CPU or migrate a new VCPU onto a CPU, or when we return to
userspace to capture the state of the VCPU for migration.  To make sure
this works, factor out the APR save/restore functionality into separate
functions called from the VCPU (and by extension VGIC) put/load hooks.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/arch/arm/include/asm/kvm_hyp.h b/arch/arm/include/asm/kvm_hyp.h
index 1ab8329e9ff75cbb617523af3e7150a3b38ba7ce..530a3c1cfe6fed8394cfcadb249f6710d06d7c93 100644 (file)
--- a/arch/arm/include/asm/kvm_hyp.h
+++ b/arch/arm/include/asm/kvm_hyp.h
@@ -110,6 +110,8 @@ void __sysreg_restore_state(struct kvm_cpu_context *ctxt);
 
 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
+void __vgic_v3_save_aprs(struct kvm_vcpu *vcpu);
+void __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu);
 
 asmlinkage void __vfp_save_state(struct vfp_hard_struct *vfp);
 asmlinkage void __vfp_restore_state(struct vfp_hard_struct *vfp);

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index febe417b8b4efa1d4a8920febabdfd1bbcc7fcae..6f3929b2fcf7b18d9ab41d7f2586d6142ddf49a3 100644 (file)
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -124,6 +124,8 @@ int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu);
 
 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
+void __vgic_v3_save_aprs(struct kvm_vcpu *vcpu);
+void __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu);
 int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
 
 void __timer_enable_traps(struct kvm_vcpu *vcpu);

diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
index 9abf2f3c12b5dabf596e37d409ce29709a0ef6c7..437d7af0868308959ffddf3de3a46010757774a5 100644 (file)
--- a/virt/kvm/arm/hyp/vgic-v3-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
@@ -21,6 +21,7 @@
 
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
 
 #define vtr_to_max_lr_idx(v)           ((v) & 0xf)
 #define vtr_to_nr_pre_bits(v)          ((((u32)(v) >> 26) & 7) + 1)
@@ -221,14 +222,11 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
 
        if (used_lrs) {
                int i;
-               u32 nr_pre_bits;
                u32 elrsr;
 
                elrsr = read_gicreg(ICH_ELSR_EL2);
 
                write_gicreg(0, ICH_HCR_EL2);
-               val = read_gicreg(ICH_VTR_EL2);
-               nr_pre_bits = vtr_to_nr_pre_bits(val);
 
                for (i = 0; i < used_lrs; i++) {
                        if (elrsr & (1 << i))
@@ -238,39 +236,10 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
 
                        __gic_v3_set_lr(0, i);
                }
-
-               switch (nr_pre_bits) {
-               case 7:
-                       cpu_if->vgic_ap0r[3] = __vgic_v3_read_ap0rn(3);
-                       cpu_if->vgic_ap0r[2] = __vgic_v3_read_ap0rn(2);
-               case 6:
-                       cpu_if->vgic_ap0r[1] = __vgic_v3_read_ap0rn(1);
-               default:
-                       cpu_if->vgic_ap0r[0] = __vgic_v3_read_ap0rn(0);
-               }
-
-               switch (nr_pre_bits) {
-               case 7:
-                       cpu_if->vgic_ap1r[3] = __vgic_v3_read_ap1rn(3);
-                       cpu_if->vgic_ap1r[2] = __vgic_v3_read_ap1rn(2);
-               case 6:
-                       cpu_if->vgic_ap1r[1] = __vgic_v3_read_ap1rn(1);
-               default:
-                       cpu_if->vgic_ap1r[0] = __vgic_v3_read_ap1rn(0);
-               }
        } else {
                if (static_branch_unlikely(&vgic_v3_cpuif_trap) ||
                    cpu_if->its_vpe.its_vm)
                        write_gicreg(0, ICH_HCR_EL2);
-
-               cpu_if->vgic_ap0r[0] = 0;
-               cpu_if->vgic_ap0r[1] = 0;
-               cpu_if->vgic_ap0r[2] = 0;
-               cpu_if->vgic_ap0r[3] = 0;
-               cpu_if->vgic_ap1r[0] = 0;
-               cpu_if->vgic_ap1r[1] = 0;
-               cpu_if->vgic_ap1r[2] = 0;
-               cpu_if->vgic_ap1r[3] = 0;
        }
 
        val = read_gicreg(ICC_SRE_EL2);
@@ -287,8 +256,6 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
 {
        struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
        u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
-       u64 val;
-       u32 nr_pre_bits;
        int i;
 
        /*
@@ -306,32 +273,9 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
                write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
        }
 
-       val = read_gicreg(ICH_VTR_EL2);
-       nr_pre_bits = vtr_to_nr_pre_bits(val);
-
        if (used_lrs) {
                write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
 
-               switch (nr_pre_bits) {
-               case 7:
-                       __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[3], 3);
-                       __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[2], 2);
-               case 6:
-                       __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[1], 1);
-               default:
-                       __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[0], 0);
-               }
-
-               switch (nr_pre_bits) {
-               case 7:
-                       __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[3], 3);
-                       __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[2], 2);
-               case 6:
-                       __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[1], 1);
-               default:
-                       __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[0], 0);
-               }
-
                for (i = 0; i < used_lrs; i++)
                        __gic_v3_set_lr(cpu_if->vgic_lr[i], i);
        } else {
@@ -364,6 +308,72 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
                     ICC_SRE_EL2);
 }
 
+void __hyp_text __vgic_v3_save_aprs(struct kvm_vcpu *vcpu)
+{
+       struct vgic_v3_cpu_if *cpu_if;
+       u64 val;
+       u32 nr_pre_bits;
+
+       vcpu = kern_hyp_va(vcpu);
+       cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
+
+       val = read_gicreg(ICH_VTR_EL2);
+       nr_pre_bits = vtr_to_nr_pre_bits(val);
+
+       switch (nr_pre_bits) {
+       case 7:
+               cpu_if->vgic_ap0r[3] = __vgic_v3_read_ap0rn(3);
+               cpu_if->vgic_ap0r[2] = __vgic_v3_read_ap0rn(2);
+       case 6:
+               cpu_if->vgic_ap0r[1] = __vgic_v3_read_ap0rn(1);
+       default:
+               cpu_if->vgic_ap0r[0] = __vgic_v3_read_ap0rn(0);
+       }
+
+       switch (nr_pre_bits) {
+       case 7:
+               cpu_if->vgic_ap1r[3] = __vgic_v3_read_ap1rn(3);
+               cpu_if->vgic_ap1r[2] = __vgic_v3_read_ap1rn(2);
+       case 6:
+               cpu_if->vgic_ap1r[1] = __vgic_v3_read_ap1rn(1);
+       default:
+               cpu_if->vgic_ap1r[0] = __vgic_v3_read_ap1rn(0);
+       }
+}
+
+void __hyp_text __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu)
+{
+       struct vgic_v3_cpu_if *cpu_if;
+       u64 val;
+       u32 nr_pre_bits;
+
+       vcpu = kern_hyp_va(vcpu);
+       cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
+
+       val = read_gicreg(ICH_VTR_EL2);
+       nr_pre_bits = vtr_to_nr_pre_bits(val);
+
+       switch (nr_pre_bits) {
+       case 7:
+               __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[3], 3);
+               __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[2], 2);
+       case 6:
+               __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[1], 1);
+       default:
+               __vgic_v3_write_ap0rn(cpu_if->vgic_ap0r[0], 0);
+       }
+
+       switch (nr_pre_bits) {
+       case 7:
+               __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[3], 3);
+               __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[2], 2);
+       case 6:
+               __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[1], 1);
+       default:
+               __vgic_v3_write_ap1rn(cpu_if->vgic_ap1r[0], 0);
+       }
+}
+
 void __hyp_text __vgic_v3_init_lrs(void)
 {
        int max_lr_idx = vtr_to_max_lr_idx(read_gicreg(ICH_VTR_EL2));

diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index 1e5f3eb6973d78b04629253a30f1e2ad35f915d4..ca7cfee9f35342b0ba2c2b53b5f6fcd44d65966c 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -446,7 +446,6 @@ void vgic_v2_save_state(struct kvm_vcpu *vcpu)
 {
        struct kvm *kvm = vcpu->kvm;
        struct vgic_dist *vgic = &kvm->arch.vgic;
-       struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
        void __iomem *base = vgic->vctrl_base;
        u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
 
@@ -454,11 +453,8 @@ void vgic_v2_save_state(struct kvm_vcpu *vcpu)
                return;
 
        if (used_lrs) {
-               cpu_if->vgic_apr = readl_relaxed(base + GICH_APR);
                save_lrs(vcpu, base);
                writel_relaxed(0, base + GICH_HCR);
-       } else {
-               cpu_if->vgic_apr = 0;
        }
 }
 
@@ -476,7 +472,6 @@ void vgic_v2_restore_state(struct kvm_vcpu *vcpu)
 
        if (used_lrs) {
                writel_relaxed(cpu_if->vgic_hcr, base + GICH_HCR);
-               writel_relaxed(cpu_if->vgic_apr, base + GICH_APR);
                for (i = 0; i < used_lrs; i++) {
                        writel_relaxed(cpu_if->vgic_lr[i],
                                       base + GICH_LR0 + (i * 4));
@@ -490,6 +485,7 @@ void vgic_v2_load(struct kvm_vcpu *vcpu)
        struct vgic_dist *vgic = &vcpu->kvm->arch.vgic;
 
        writel_relaxed(cpu_if->vgic_vmcr, vgic->vctrl_base + GICH_VMCR);
+       writel_relaxed(cpu_if->vgic_apr, vgic->vctrl_base + GICH_APR);
 }
 
 void vgic_v2_put(struct kvm_vcpu *vcpu)
@@ -498,4 +494,5 @@ void vgic_v2_put(struct kvm_vcpu *vcpu)
        struct vgic_dist *vgic = &vcpu->kvm->arch.vgic;
 
        cpu_if->vgic_vmcr = readl_relaxed(vgic->vctrl_base + GICH_VMCR);
+       cpu_if->vgic_apr = readl_relaxed(vgic->vctrl_base + GICH_APR);
 }

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index b76e21f3e6bd76b5685a87058a37d65ece38705a..4bafcd1e6bb8af678d26502d5894284878d77cc6 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -16,6 +16,7 @@
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <kvm/arm_vgic.h>
+#include <asm/kvm_hyp.h>
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_asm.h>
 
@@ -587,6 +588,8 @@ void vgic_v3_load(struct kvm_vcpu *vcpu)
         */
        if (likely(cpu_if->vgic_sre))
                kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr);
+
+       kvm_call_hyp(__vgic_v3_restore_aprs, vcpu);
 }
 
 void vgic_v3_put(struct kvm_vcpu *vcpu)
@@ -595,4 +598,6 @@ void vgic_v3_put(struct kvm_vcpu *vcpu)
 
        if (likely(cpu_if->vgic_sre))
                cpu_if->vgic_vmcr = kvm_call_hyp(__vgic_v3_read_vmcr);
+
+       kvm_call_hyp(__vgic_v3_save_aprs, vcpu);
 }