arm64: KVM: Switch vgic save/restore to alternative_insn
So far, we configured the world-switch by having a small array
of pointers to the save and restore functions, depending on the
GIC used on the platform.
Loading these values each time is a bit silly (they never change),
and it makes sense to rely on the instruction patching instead.
This leads to a nice cleanup of the code.
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 8a14849b4a355278f0b7baf6e2da7dc7144a23e8)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Conflicts:
arch/arm64/include/asm/kvm_asm.h
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 825c337..dcba0fa 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -218,11 +218,6 @@
return 0;
}
-static inline void vgic_arch_setup(const struct vgic_params *vgic)
-{
- BUG_ON(vgic->type != VGIC_V2);
-}
-
int kvm_perf_init(void);
int kvm_perf_teardown(void);
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 9ccdd4b..69287f1 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -236,29 +236,6 @@
void *restore_vgic;
};
-static inline void vgic_arch_setup(const struct vgic_params *vgic)
-{
- extern struct vgic_sr_vectors __vgic_sr_vectors;
-
- switch(vgic->type)
- {
- case VGIC_V2:
- __vgic_sr_vectors.save_vgic = __save_vgic_v2_state;
- __vgic_sr_vectors.restore_vgic = __restore_vgic_v2_state;
- break;
-
-#ifdef CONFIG_ARM_GIC_V3
- case VGIC_V3:
- __vgic_sr_vectors.save_vgic = __save_vgic_v3_state;
- __vgic_sr_vectors.restore_vgic = __restore_vgic_v3_state;
- break;
-#endif
-
- default:
- BUG();
- }
-}
-
static inline void kvm_arch_hardware_disable(void) {}
static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 03937c1..1f5eafb 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -135,7 +135,6 @@
DEFINE(VCPU_VGIC_CPU, offsetof(struct kvm_vcpu, arch.vgic_cpu));
DEFINE(VGIC_SAVE_FN, offsetof(struct vgic_sr_vectors, save_vgic));
DEFINE(VGIC_RESTORE_FN, offsetof(struct vgic_sr_vectors, restore_vgic));
- DEFINE(VGIC_SR_VECTOR_SZ, sizeof(struct vgic_sr_vectors));
DEFINE(VGIC_V2_CPU_HCR, offsetof(struct vgic_cpu, vgic_v2.vgic_hcr));
DEFINE(VGIC_V2_CPU_VMCR, offsetof(struct vgic_cpu, vgic_v2.vgic_vmcr));
DEFINE(VGIC_V2_CPU_MISR, offsetof(struct vgic_cpu, vgic_v2.vgic_misr));
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index 89c0755..6288cd6 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -17,8 +17,10 @@
#include <linux/linkage.h>
+#include <asm/alternative.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
+#include <asm/cpufeature.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/fpsimdmacros.h>
@@ -509,10 +511,7 @@
* Call into the vgic backend for state saving
*/
.macro save_vgic_state
- adr x24, __vgic_sr_vectors
- ldr x24, [x24, VGIC_SAVE_FN]
- kern_hyp_va x24
- blr x24
+ alternative_insn "bl __save_vgic_v2_state", "bl __save_vgic_v3_state", ARM64_HAS_SYSREG_GIC_CPUIF
mrs x24, hcr_el2
mov x25, #HCR_INT_OVERRIDE
neg x25, x25
@@ -529,10 +528,7 @@
orr x24, x24, #HCR_INT_OVERRIDE
orr x24, x24, x25
msr hcr_el2, x24
- adr x24, __vgic_sr_vectors
- ldr x24, [x24, #VGIC_RESTORE_FN]
- kern_hyp_va x24
- blr x24
+ alternative_insn "bl __restore_vgic_v2_state", "bl __restore_vgic_v3_state", ARM64_HAS_SYSREG_GIC_CPUIF
.endm
.macro save_timer_state
@@ -823,12 +819,6 @@
ret
ENDPROC(__kvm_flush_vm_context)
- // struct vgic_sr_vectors __vgi_sr_vectors;
- .align 3
-ENTRY(__vgic_sr_vectors)
- .skip VGIC_SR_VECTOR_SZ
-ENDPROC(__vgic_sr_vectors)
-
__kvm_hyp_panic:
// Guess the context by looking at VTTBR:
// If zero, then we're already a host.
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 934d56f..5309b2e 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -2128,9 +2128,6 @@
goto out_free_irq;
}
- /* Callback into for arch code for setup */
- vgic_arch_setup(vgic);
-
on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
return 0;