[PATCH v2 03/28] ARM: KVM: Move VFP registers to a CPU context structure

Marc Zyngier
2016-02-04T11:00:20Z

In order to turn the WS code into something that looks a bit
more like the arm64 version, move the VFP registers into a
CPU context container for both the host and the guest.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_host.h | 11 +++++++----
arch/arm/kernel/asm-offsets.c | 5 +++--
arch/arm/kvm/coproc.c | 20 ++++++++++----------
arch/arm/kvm/interrupts.S | 10 ++++++----
4 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index f1e86f1..b64ac8e 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -88,9 +88,15 @@ struct kvm_vcpu_fault_info {
u32 hyp_pc; /* PC when exception was taken from Hyp mode */
};

-typedef struct vfp_hard_struct kvm_cpu_context_t;
+struct kvm_cpu_context {
+ struct vfp_hard_struct vfp;
+};
+
+typedef struct kvm_cpu_context kvm_cpu_context_t;

struct kvm_vcpu_arch {
+ struct kvm_cpu_context ctxt;
+
struct kvm_regs regs;

int target; /* Processor target */
@@ -111,9 +117,6 @@ struct kvm_vcpu_arch {
/* Exception Information */
struct kvm_vcpu_fault_info fault;

- /* Floating point registers (VFP and Advanced SIMD/NEON) */
- struct vfp_hard_struct vfp_guest;
-
/* Host FP context */
kvm_cpu_context_t *host_cpu_context;

diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 871b826..346bfca 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -173,8 +173,9 @@ int main(void)
DEFINE(VCPU_KVM, offsetof(struct kvm_vcpu, kvm));
DEFINE(VCPU_MIDR, offsetof(struct kvm_vcpu, arch.midr));
DEFINE(VCPU_CP15, offsetof(struct kvm_vcpu, arch.cp15));
- DEFINE(VCPU_VFP_GUEST, offsetof(struct kvm_vcpu, arch.vfp_guest));
- DEFINE(VCPU_VFP_HOST, offsetof(struct kvm_vcpu, arch.host_cpu_context));
+ DEFINE(VCPU_GUEST_CTXT, offsetof(struct kvm_vcpu, arch.ctxt));
+ DEFINE(VCPU_HOST_CTXT, offsetof(struct kvm_vcpu, arch.host_cpu_context));
+ DEFINE(CPU_CTXT_VFP, offsetof(struct kvm_cpu_context, vfp));
DEFINE(VCPU_REGS, offsetof(struct kvm_vcpu, arch.regs));
DEFINE(VCPU_USR_REGS, offsetof(struct kvm_vcpu, arch.regs.usr_regs));
DEFINE(VCPU_SVC_REGS, offsetof(struct kvm_vcpu, arch.regs.svc_regs));
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index f3d88dc..1a643f3 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -901,7 +901,7 @@ static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)
if (vfpid < num_fp_regs()) {
if (KVM_REG_SIZE(id) != 8)
return -ENOENT;
- return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpregs[vfpid],
+ return reg_to_user(uaddr, &vcpu->arch.ctxt.vfp.fpregs[vfpid],
id);
}

@@ -911,13 +911,13 @@ static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)

switch (vfpid) {
case KVM_REG_ARM_VFP_FPEXC:
- return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpexc, id);
+ return reg_to_user(uaddr, &vcpu->arch.ctxt.vfp.fpexc, id);
case KVM_REG_ARM_VFP_FPSCR:
- return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpscr, id);
+ return reg_to_user(uaddr, &vcpu->arch.ctxt.vfp.fpscr, id);
case KVM_REG_ARM_VFP_FPINST:
- return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst, id);
+ return reg_to_user(uaddr, &vcpu->arch.ctxt.vfp.fpinst, id);
case KVM_REG_ARM_VFP_FPINST2:
- return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst2, id);
+ return reg_to_user(uaddr, &vcpu->arch.ctxt.vfp.fpinst2, id);
case KVM_REG_ARM_VFP_MVFR0:
val = fmrx(MVFR0);
return reg_to_user(uaddr, &val, id);
@@ -945,7 +945,7 @@ static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)
if (vfpid < num_fp_regs()) {
if (KVM_REG_SIZE(id) != 8)
return -ENOENT;
- return reg_from_user(&vcpu->arch.vfp_guest.fpregs[vfpid],
+ return reg_from_user(&vcpu->arch.ctxt.vfp.fpregs[vfpid],
uaddr, id);
}

@@ -955,13 +955,13 @@ static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)

switch (vfpid) {
case KVM_REG_ARM_VFP_FPEXC:
- return reg_from_user(&vcpu->arch.vfp_guest.fpexc, uaddr, id);
+ return reg_from_user(&vcpu->arch.ctxt.vfp.fpexc, uaddr, id);
case KVM_REG_ARM_VFP_FPSCR:
- return reg_from_user(&vcpu->arch.vfp_guest.fpscr, uaddr, id);
+ return reg_from_user(&vcpu->arch.ctxt.vfp.fpscr, uaddr, id);
case KVM_REG_ARM_VFP_FPINST:
- return reg_from_user(&vcpu->arch.vfp_guest.fpinst, uaddr, id);
+ return reg_from_user(&vcpu->arch.ctxt.vfp.fpinst, uaddr, id);
case KVM_REG_ARM_VFP_FPINST2:
- return reg_from_user(&vcpu->arch.vfp_guest.fpinst2, uaddr, id);
+ return reg_from_user(&vcpu->arch.ctxt.vfp.fpinst2, uaddr, id);
/* These are invariant. */
case KVM_REG_ARM_VFP_MVFR0:
if (reg_from_user(&val, uaddr, id))
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 9d9cb71..7bfb289 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -172,10 +172,11 @@ __kvm_vcpu_return:

#ifdef CONFIG_VFPv3
@ Switch VFP/NEON hardware state to the host's
- add r7, vcpu, #VCPU_VFP_GUEST
+ add r7, vcpu, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
store_vfp_state r7
- add r7, vcpu, #VCPU_VFP_HOST
+ add r7, vcpu, #VCPU_HOST_CTXT
ldr r7, [r7]
+ add r7, r7, #CPU_CTXT_VFP
restore_vfp_state r7

after_vfp_restore:
@@ -482,10 +483,11 @@ switch_to_guest_vfp:
set_hcptr vmtrap, (HCPTR_TCP(10) | HCPTR_TCP(11))

@ Switch VFP/NEON hardware state to the guest's
- add r7, r0, #VCPU_VFP_HOST
+ add r7, r0, #VCPU_HOST_CTXT
ldr r7, [r7]
+ add r7, r7, #CPU_CTXT_VFP
store_vfp_state r7
- add r7, r0, #VCPU_VFP_GUEST
+ add r7, r0, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
restore_vfp_state r7

pop {r3-r7}
--
2.1.4