[PATCH 11/12] KVM: ARM: on IO mem abort - route the call to KVM MMIO bus

Andre Przywara andre.przywara at arm.com
Fri Mar 13 09:10:11 PDT 2015


From: Nikolay Nikolaev <n.nikolaev at virtualopensystems.com>

On IO memory abort, try to handle the MMIO access through the KVM
registered read/write callbacks. This is done by invoking the relevant
kvm_io_bus_* API.

[Andre: Since we converted the VGIC already, we can get rid of the
VGIC specific MMIO handler alltogether.]

Signed-off-by: Nikolay Nikolaev <n.nikolaev at virtualopensystems.com>
Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 arch/arm/kvm/mmio.c    |   32 +++++++++++++++++++++++++++++++-
 include/kvm/arm_vgic.h |    2 --
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c
index 5d3bfc0..8dc2fde 100644
--- a/arch/arm/kvm/mmio.c
+++ b/arch/arm/kvm/mmio.c
@@ -162,6 +162,36 @@ static int decode_hsr(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	return 0;
 }
 
+/**
+ * handle_kernel_mmio - handle an in-kernel MMIO access
+ * @vcpu:	pointer to the vcpu performing the access
+ * @run:	pointer to the kvm_run structure
+ * @mmio:	pointer to the data describing the access
+ *
+ * returns true if the MMIO access has been performed in kernel space,
+ * and false if it needs to be emulated in user space.
+ */
+static bool handle_kernel_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
+		struct kvm_exit_mmio *mmio)
+{
+	int ret;
+
+	if (mmio->is_write) {
+		ret = kvm_io_bus_write(vcpu, KVM_MMIO_BUS, mmio->phys_addr,
+				mmio->len, &mmio->data);
+
+	} else {
+		ret = kvm_io_bus_read(vcpu, KVM_MMIO_BUS, mmio->phys_addr,
+				mmio->len, &mmio->data);
+	}
+	if (!ret) {
+		kvm_prepare_mmio(run, mmio);
+		kvm_handle_mmio_return(vcpu, run);
+	}
+
+	return !ret;
+}
+
 int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
 		 phys_addr_t fault_ipa)
 {
@@ -200,7 +230,7 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
 			       fault_ipa, 0);
 	}
 
-	if (vgic_handle_mmio(vcpu, run, &mmio))
+	if (handle_kernel_mmio(vcpu, run, &mmio))
 		return 1;
 
 	kvm_prepare_mmio(run, &mmio);
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 09fd324..91976c8 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -317,8 +317,6 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
 			bool level);
 void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg);
 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
-bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
-		      struct kvm_exit_mmio *mmio);
 
 #define irqchip_in_kernel(k)	(!!((k)->arch.vgic.in_kernel))
 #define vgic_initialized(k)	(!!((k)->arch.vgic.nr_cpus))
-- 
1.7.9.5




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