KVM: PPC: Add return value in prepare_to_enter

Our prepare_to_enter helper wants to be able to return in more circumstances
to the host than only when an interrupt is pending. Broaden the interface a
bit and move even more generic code to the generic helper.

Signed-off-by: Alexander Graf <agraf@suse.de>

3 files changed, 22 insertions, 17 deletions

diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 1ff0d6ccc589..71fa0f1873b3 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -589,6 +589,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
                        unsigned int exit_nr)
 {
         int r = RESUME_HOST;
+        int s;
 
         vcpu->stat.sum_exits++;
 
@@ -862,10 +863,10 @@ program_interrupt:
                  * again due to a host external interrupt.
                  */
                 local_irq_disable();
-                if (kvmppc_prepare_to_enter(vcpu)) {
+                s = kvmppc_prepare_to_enter(vcpu);
+                if (s <= 0) {
                         local_irq_enable();
-                        run->exit_reason = KVM_EXIT_INTR;
-                        r = -EINTR;
+                        r = s;
                 } else {
                         kvmppc_lazy_ee_enable();
                 }
@@ -1074,10 +1075,9 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
          * a host external interrupt.
          */
         local_irq_disable();
-        if (kvmppc_prepare_to_enter(vcpu)) {
+        ret = kvmppc_prepare_to_enter(vcpu);
+        if (ret <= 0) {
                 local_irq_enable();
-                kvm_run->exit_reason = KVM_EXIT_INTR;
-                ret = -EINTR;
                 goto out;
         }
 
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 5e8dc1909130..1917802463f5 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -467,7 +467,7 @@ void kvmppc_core_check_requests(struct kvm_vcpu *vcpu)
 
 int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
 {
-        int ret;
+        int ret, s;
 #ifdef CONFIG_PPC_FPU
         unsigned int fpscr;
         int fpexc_mode;
@@ -480,10 +480,10 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
         }
 
         local_irq_disable();
-        if (kvmppc_prepare_to_enter(vcpu)) {
+        s = kvmppc_prepare_to_enter(vcpu);
+        if (s <= 0) {
                 local_irq_enable();
-                kvm_run->exit_reason = KVM_EXIT_INTR;
-                ret = -EINTR;
+                ret = s;
                 goto out;
         }
         kvmppc_lazy_ee_enable();
@@ -642,6 +642,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
                        unsigned int exit_nr)
 {
         int r = RESUME_HOST;
+        int s;
 
         /* update before a new last_exit_type is rewritten */
         kvmppc_update_timing_stats(vcpu);
@@ -948,11 +949,10 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
          */
         if (!(r & RESUME_HOST)) {
                 local_irq_disable();
-                if (kvmppc_prepare_to_enter(vcpu)) {
+                s = kvmppc_prepare_to_enter(vcpu);
+                if (s <= 0) {
                         local_irq_enable();
-                        run->exit_reason = KVM_EXIT_INTR;
-                        r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
-                        kvmppc_account_exit(vcpu, SIGNAL_EXITS);
+                        r = (s << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
                 } else {
                         kvmppc_lazy_ee_enable();
                 }
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index dc86371b9953..0e2a98ab6a77 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -53,11 +53,14 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  * Common checks before entering the guest world.  Call with interrupts
  * disabled.
  *
- * returns !0 if a signal is pending and check_signal is true
+ * returns:
+ *
+ * == 1 if we're ready to go into guest state
+ * <= 0 if we need to go back to the host with return value
  */
 int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu)
 {
-        int r = 0;
+        int r = 1;
 
         WARN_ON_ONCE(!irqs_disabled());
         while (true) {
@@ -69,7 +72,9 @@ int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu)
                 }
 
                 if (signal_pending(current)) {
-                        r = 1;
+                        kvmppc_account_exit(vcpu, SIGNAL_EXITS);
+                        vcpu->run->exit_reason = KVM_EXIT_INTR;
+                        r = -EINTR;
                         break;
                 }