[PATCH 3/7] KVM: arm: vgic-new: improve compatibility with 32-bit

Vladimir Murzin vladimir.murzin at arm.com
Mon Jul 18 03:48:15 PDT 2016


We have couple of 64-bit register defined in GICv3 architecture, so
"unsigned long" kind of accessors wouldn't work for 32-bit. However,
these registers can't be access as 64-bit in a one go if we run 32-bit
host simply beacuse KVM doesn't support multiple load/store on MMIO
space.

It means that 32-bit guest accesses these registers in 32-bit chunks, so
the only thing we need to do is to ensure that extract_bytes() always
takes 64-bit data.

Since we are here fix couple of other width releated issues by using
ULL varians over UL.

Signed-off-by: Vladimir Murzin <vladimir.murzin at arm.com>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index a0c515a..a266304 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -23,7 +23,7 @@
 #include "vgic-mmio.h"
 
 /* extract @num bytes at @offset bytes offset in data */
-static unsigned long extract_bytes(unsigned long data, unsigned int offset,
+static unsigned long extract_bytes(u64 data, unsigned int offset,
 				   unsigned int num)
 {
 	return (data >> (offset * 8)) & GENMASK_ULL(num * 8 - 1, 0);
@@ -121,7 +121,7 @@ static unsigned long vgic_mmio_read_v3r_typer(struct kvm_vcpu *vcpu,
 	int target_vcpu_id = vcpu->vcpu_id;
 	u64 value;
 
-	value = (mpidr & GENMASK(23, 0)) << 32;
+	value = (mpidr & GENMASK_ULL(23, 0)) << 32;
 	value |= ((target_vcpu_id & 0xffff) << 8);
 	if (target_vcpu_id == atomic_read(&vcpu->kvm->online_vcpus) - 1)
 		value |= GICR_TYPER_LAST;
@@ -411,7 +411,7 @@ void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg)
 	bool broadcast;
 
 	sgi = (reg & ICC_SGI1R_SGI_ID_MASK) >> ICC_SGI1R_SGI_ID_SHIFT;
-	broadcast = reg & BIT(ICC_SGI1R_IRQ_ROUTING_MODE_BIT);
+	broadcast = reg & BIT_ULL(ICC_SGI1R_IRQ_ROUTING_MODE_BIT);
 	target_cpus = (reg & ICC_SGI1R_TARGET_LIST_MASK) >> ICC_SGI1R_TARGET_LIST_SHIFT;
 	mpidr = SGI_AFFINITY_LEVEL(reg, 3);
 	mpidr |= SGI_AFFINITY_LEVEL(reg, 2);
-- 
1.7.9.5




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