[PATCH 3/5] KVM: arm64: Consolidate REG_HIDDEN_GUEST/USER

Marc Zyngier
2020-11-06T16:44:44Z

REG_HIDDEN_GUEST and REG_HIDDEN_USER are always used together.
Consolidate them into a single REG_HIDDEN flag. We can always
add another flag later if some register needs to expose itself
differently to the guest than it does to userspace.

No functional change intended.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201105091022.15373-3-drjones@redhat.com
---
arch/arm64/kvm/sys_regs.c | 12 ++++++------
arch/arm64/kvm/sys_regs.h | 18 ++++--------------
2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 3af306e6b9cd..26a285127620 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1069,7 +1069,7 @@ static bool trap_ptrauth(struct kvm_vcpu *vcpu,
static unsigned int ptrauth_visibility(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd)
{
- return vcpu_has_ptrauth(vcpu) ? 0 : REG_HIDDEN_USER | REG_HIDDEN_GUEST;
+ return vcpu_has_ptrauth(vcpu) ? 0 : REG_HIDDEN;
}

#define __PTRAUTH_KEY(k) \
@@ -1190,7 +1190,7 @@ static unsigned int sve_visibility(const struct kvm_vcpu *vcpu,
if (vcpu_has_sve(vcpu))
return 0;

- return REG_HIDDEN_USER | REG_HIDDEN_GUEST;
+ return REG_HIDDEN;
}

/* Generate the emulated ID_AA64ZFR0_EL1 value exposed to the guest */
@@ -2153,7 +2153,7 @@ static void perform_access(struct kvm_vcpu *vcpu,
trace_kvm_sys_access(*vcpu_pc(vcpu), params, r);

/* Check for regs disabled by runtime config */
- if (sysreg_hidden_from_guest(vcpu, r)) {
+ if (sysreg_hidden(vcpu, r)) {
kvm_inject_undefined(vcpu);
return;
}
@@ -2652,7 +2652,7 @@ int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg
return get_invariant_sys_reg(reg->id, uaddr);

/* Check for regs disabled by runtime config */
- if (sysreg_hidden_from_user(vcpu, r))
+ if (sysreg_hidden(vcpu, r))
return -ENOENT;

if (r->get_user)
@@ -2677,7 +2677,7 @@ int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg
return set_invariant_sys_reg(reg->id, uaddr);

/* Check for regs disabled by runtime config */
- if (sysreg_hidden_from_user(vcpu, r))
+ if (sysreg_hidden(vcpu, r))
return -ENOENT;

if (r->set_user)
@@ -2748,7 +2748,7 @@ static int walk_one_sys_reg(const struct kvm_vcpu *vcpu,
if (!(rd->reg || rd->get_user))
return 0;

- if (sysreg_hidden_from_user(vcpu, rd))
+ if (sysreg_hidden(vcpu, rd))
return 0;

if (!copy_reg_to_user(rd, uind))
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h
index 5a6fc30f5989..2641b2ee6a91 100644
--- a/arch/arm64/kvm/sys_regs.h
+++ b/arch/arm64/kvm/sys_regs.h
@@ -59,8 +59,7 @@ struct sys_reg_desc {
const struct sys_reg_desc *rd);
};

-#define REG_HIDDEN_USER (1 << 0) /* hidden from userspace ioctls */
-#define REG_HIDDEN_GUEST (1 << 1) /* hidden from guest */
+#define REG_HIDDEN (1 << 0) /* hidden from userspace and guest */

static __printf(2, 3)
inline void print_sys_reg_msg(const struct sys_reg_params *p,
@@ -111,22 +110,13 @@ static inline void reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r
__vcpu_sys_reg(vcpu, r->reg) = r->val;
}

-static inline bool sysreg_hidden_from_guest(const struct kvm_vcpu *vcpu,
- const struct sys_reg_desc *r)
-{
- if (likely(!r->visibility))
- return false;
-
- return r->visibility(vcpu, r) & REG_HIDDEN_GUEST;
-}
-
-static inline bool sysreg_hidden_from_user(const struct kvm_vcpu *vcpu,
- const struct sys_reg_desc *r)
+static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu,
+ const struct sys_reg_desc *r)
{
if (likely(!r->visibility))
return false;

- return r->visibility(vcpu, r) & REG_HIDDEN_USER;
+ return r->visibility(vcpu, r) & REG_HIDDEN;
}

static inline int cmp_sys_reg(const struct sys_reg_desc *i1,
--
2.28.0