From e8e7fcc5e2710b31ef842ee799db99c07986c364 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Tue, 29 Apr 2014 11:24:18 +0530 Subject: ARM/ARM64: KVM: Make kvm_psci_call() return convention more flexible Currently, the kvm_psci_call() returns 'true' or 'false' based on whether the PSCI function call was handled successfully or not. This does not help us emulate system-level PSCI functions where the actual emulation work will be done by user space (QEMU or KVMTOOL). Examples of such system-level PSCI functions are: PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET. This patch updates kvm_psci_call() to return three types of values: 1) > 0 (success) 2) = 0 (success but exit to user space) 3) < 0 (errors) Signed-off-by: Anup Patel Signed-off-by: Pranavkumar Sawargaonkar Reviewed-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/psci.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) (limited to 'arch/arm/kvm/psci.c') diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 8c42596c..14e6fa6 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -93,7 +93,7 @@ int kvm_psci_version(struct kvm_vcpu *vcpu) return KVM_ARM_PSCI_0_1; } -static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -128,14 +128,14 @@ static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) val = PSCI_RET_NOT_SUPPORTED; break; default: - return false; + return -EINVAL; } *vcpu_reg(vcpu, 0) = val; - return true; + return 1; } -static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) +static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -153,11 +153,11 @@ static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) val = PSCI_RET_NOT_SUPPORTED; break; default: - return false; + return -EINVAL; } *vcpu_reg(vcpu, 0) = val; - return true; + return 1; } /** @@ -165,12 +165,16 @@ static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) * @vcpu: Pointer to the VCPU struct * * Handle PSCI calls from guests through traps from HVC instructions. - * The calling convention is similar to SMC calls to the secure world where - * the function number is placed in r0 and this function returns true if the - * function number specified in r0 is withing the PSCI range, and false - * otherwise. + * The calling convention is similar to SMC calls to the secure world + * where the function number is placed in r0. + * + * This function returns: > 0 (success), 0 (success but exit to user + * space), and < 0 (errors) + * + * Errors: + * -EINVAL: Unrecognized PSCI function */ -bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_call(struct kvm_vcpu *vcpu) { switch (kvm_psci_version(vcpu)) { case KVM_ARM_PSCI_0_2: @@ -178,6 +182,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_ARM_PSCI_0_1: return kvm_psci_0_1_call(vcpu); default: - return false; + return -EINVAL; }; } -- cgit v1.1