On Sat, Dec 14, 2013 at 1:38 AM, Christoffer Dall christoffer.dall@linaro.org wrote:
On Thu, Dec 12, 2013 at 09:42:27PM +0530, Anup Patel wrote:
The PSCI SYSTEM_OFF and SYSTEM_RESET functions are system-level functions hence cannot be fully emulated by the in-kernel PSCI emulation code.
To tackle this, we forward PSCI SYSTEM_OFF and SYSTEM_RESET function calls from vcpu to user space (i.e. QEMU or KVMTOOL) via kvm_run structure using KVM_EXIT_SYSTEM_EVENT exit reasons.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
arch/arm/include/asm/kvm_psci.h | 2 +- arch/arm/include/uapi/asm/kvm.h | 2 ++ arch/arm/kvm/handle_exit.c | 13 +++++++--- arch/arm/kvm/psci.c | 48 ++++++++++++++++++++++++++++++------- arch/arm64/include/asm/kvm_psci.h | 2 +- arch/arm64/include/uapi/asm/kvm.h | 2 ++ arch/arm64/kvm/handle_exit.c | 12 +++++++--- 7 files changed, 65 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..992d7f1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,6 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__
-bool kvm_psci_call(struct kvm_vcpu *vcpu); +int kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..f4de20c 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -172,6 +172,8 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_OFF KVM_PSCI_FN(1) #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3) +#define KVM_PSCI_FN_SYSTEM_OFF KVM_PSCI_FN(4) +#define KVM_PSCI_FN_SYSTEM_RESET KVM_PSCI_FN(5)
#define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c index a920790..c3f0e72 100644 --- a/arch/arm/kvm/handle_exit.c +++ b/arch/arm/kvm/handle_exit.c @@ -40,14 +40,21 @@ static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) {
int ret;trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0), kvm_vcpu_hvc_get_imm(vcpu));
if (kvm_psci_call(vcpu))
ret = kvm_psci_call(vcpu);if (ret >= 0)return ret;else if (ret == -EINVAL) {kvm_inject_undefined(vcpu); return 1;}return ret;Wouldn't
ret = kvm_psci_call(vcpu); if (ret == -EINVAL) { kvm_inject_undefined(vcpu); return 1; }
return ret;
be simpler?
Yes, I will make this simpler.
also, minor nit, but I think according to the CodingStyle if you have single statements in if cases, but they are part of a larger if statement with alternative clauses that use curly-brackets to encapsulate multiple statements, then you should use curly braces around the single-line statement as well...
kvm_inject_undefined(vcpu);return 1;}
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 0881bf1..8e246d6 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -84,18 +84,41 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; }
+static inline void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) +{
memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));vcpu->run->system_event.type = type;vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;+}
+static void kvm_psci_system_off(struct kvm_vcpu *vcpu) +{
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN);+}
+static void kvm_psci_system_reset(struct kvm_vcpu *vcpu) +{
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);+}
/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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 and function number
the function number
- specified in r0 is withing the PSCI range.
this reads a little funny now. I think you can get rid of everything after the first mention of r0 (cut from "and function number...") since you explain that in the error codes below.
Sure, I will update this comment.
- This function returns: > 0 (success), 0 (success but exit to user
- space), and < 0 (errors)
you could use @return: instead of "This function returns", but I'm not sure if anyone actually cares.
Actually, "@returns" is correct way to specify as-per doxygen comment style for C but I have seen "Returns:" or "Returns" being used commonly in other parts of kernel. I will replace "The function returns:" with "Returns:".
- Errors:
*/
- -EINVAL: Unrecognized PSCI function
-bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_call(struct kvm_vcpu *vcpu) {
int ret = 1; unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val;@@ -111,11 +134,20 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break;
case KVM_PSCI_FN_SYSTEM_OFF:kvm_psci_system_off(vcpu);val = KVM_PSCI_RET_SUCCESS;ret = 0;break;case KVM_PSCI_FN_SYSTEM_RESET:kvm_psci_system_reset(vcpu);val = KVM_PSCI_RET_SUCCESS;ret = 0;break; default:
return false;
return -EINVAL; } *vcpu_reg(vcpu, 0) = val;
return true;
return ret;} diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..9bd0ee8 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,6 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__
-bool kvm_psci_call(struct kvm_vcpu *vcpu); +int kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..f678902 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -158,6 +158,8 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_OFF KVM_PSCI_FN(1) #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3) +#define KVM_PSCI_FN_SYSTEM_OFF KVM_PSCI_FN(4) +#define KVM_PSCI_FN_SYSTEM_RESET KVM_PSCI_FN(5)
#define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index df84d7b..e382eb8 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -30,11 +30,17 @@ typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) {
if (kvm_psci_call(vcpu))
int ret;ret = kvm_psci_call(vcpu);if (ret >= 0)return ret;else if (ret == -EINVAL) {kvm_inject_undefined(vcpu); return 1;}
kvm_inject_undefined(vcpu);return 1;
return ret;same as above.
OK.
}
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
1.7.9.5
Aside from the code formatting and commenting above, it looks pretty good to me.
-Christoffer _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm