[PATCH 6/8] KVM: PPC: Book3S: Add support for ibm,int-on/off RTAS calls

Paul Mackerras
2013-04-18T06:32:04Z

This adds support for the ibm,int-on and ibm,int-off RTAS calls to the
in-kernel XICS emulation and corrects the handling of the saved
priority by the ibm,set-xive RTAS call. With this, ibm,int-off sets
the specified interrupt's priority in its saved_priority field and
sets the priority to 0xff (the least favoured value). ibm,int-on
restores the saved_priority to the priority field, and ibm,set-xive
sets both the priority and the saved_priority to the specified
priority value.

Signed-off-by: Paul Mackerras <paulus@samba.org>
---
arch/powerpc/include/asm/kvm_ppc.h | 2 +
arch/powerpc/kvm/book3s_rtas.c | 40 +++++++++++++++++
arch/powerpc/kvm/book3s_xics.c | 84 ++++++++++++++++++++++++++++++------
arch/powerpc/kvm/book3s_xics.h | 2 +-
4 files changed, 113 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 95a44a6..962fcc6 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -174,6 +174,8 @@ extern int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server,
u32 priority);
extern int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server,
u32 *priority);
+extern int kvmppc_xics_int_on(struct kvm *kvm, u32 irq);
+extern int kvmppc_xics_int_off(struct kvm *kvm, u32 irq);

/*
* Cuts out inst bits with ordering according to spec.
diff --git a/arch/powerpc/kvm/book3s_rtas.c b/arch/powerpc/kvm/book3s_rtas.c
index 44d652a..8e61156 100644
--- a/arch/powerpc/kvm/book3s_rtas.c
+++ b/arch/powerpc/kvm/book3s_rtas.c
@@ -63,6 +63,44 @@ static void kvm_rtas_get_xive(struct kvm_vcpu *vcpu, struct rtas_args *args)
out:
args->rets[0] = rc;
}
+
+static void kvm_rtas_int_off(struct kvm_vcpu *vcpu, struct rtas_args *args)
+{
+ u32 irq;
+ int rc;
+
+ if (args->nargs != 1 || args->nret != 1) {
+ rc = -3;
+ goto out;
+ }
+
+ irq = args->args[0];
+
+ rc = kvmppc_xics_int_off(vcpu->kvm, irq);
+ if (rc)
+ rc = -3;
+out:
+ args->rets[0] = rc;
+}
+
+static void kvm_rtas_int_on(struct kvm_vcpu *vcpu, struct rtas_args *args)
+{
+ u32 irq;
+ int rc;
+
+ if (args->nargs != 1 || args->nret != 1) {
+ rc = -3;
+ goto out;
+ }
+
+ irq = args->args[0];
+
+ rc = kvmppc_xics_int_on(vcpu->kvm, irq);
+ if (rc)
+ rc = -3;
+out:
+ args->rets[0] = rc;
+}
#endif /* CONFIG_KVM_XICS */

struct rtas_handler {
@@ -74,6 +112,8 @@ static struct rtas_handler rtas_handlers[] = {
#ifdef CONFIG_KVM_XICS
{ .name = "ibm,set-xive", .handler = kvm_rtas_set_xive },
{ .name = "ibm,get-xive", .handler = kvm_rtas_get_xive },
+ { .name = "ibm,int-off", .handler = kvm_rtas_int_off },
+ { .name = "ibm,int-on", .handler = kvm_rtas_int_on },
#endif
};

diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c
index 7fd247c..9fb2d39 100644
--- a/arch/powerpc/kvm/book3s_xics.c
+++ b/arch/powerpc/kvm/book3s_xics.c
@@ -123,6 +123,28 @@ static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
mutex_unlock(&ics->lock);
}

+static bool write_xive(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
+ struct ics_irq_state *state,
+ u32 server, u32 priority, u32 saved_priority)
+{
+ bool deliver;
+
+ mutex_lock(&ics->lock);
+
+ state->server = server;
+ state->priority = priority;
+ state->saved_priority = saved_priority;
+ deliver = false;
+ if ((state->masked_pending || state->resend) && priority != MASKED) {
+ state->masked_pending = 0;
+ deliver = true;
+ }
+
+ mutex_unlock(&ics->lock);
+
+ return deliver;
+}
+
int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority)
{
struct kvmppc_xics *xics = kvm->arch.xics;
@@ -130,7 +152,6 @@ int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority)
struct kvmppc_ics *ics;
struct ics_irq_state *state;
u16 src;
- bool deliver;

if (!xics)
return -ENODEV;
@@ -144,23 +165,11 @@ int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority)
if (!icp)
return -EINVAL;

- mutex_lock(&ics->lock);
-
XICS_DBG("set_xive %#x server %#x prio %#x MP:%d RS:%d\n",
irq, server, priority,
state->masked_pending, state->resend);

- state->server = server;
- state->priority = priority;
- deliver = false;
- if ((state->masked_pending || state->resend) && priority != MASKED) {
- state->masked_pending = 0;
- deliver = true;
- }
-
- mutex_unlock(&ics->lock);
-
- if (deliver)
+ if (write_xive(xics, ics, state, server, priority, priority))
icp_deliver_irq(xics, icp, irq);

return 0;
@@ -189,6 +198,53 @@ int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority)
return 0;
}

+int kvmppc_xics_int_on(struct kvm *kvm, u32 irq)
+{
+ struct kvmppc_xics *xics = kvm->arch.xics;
+ struct kvmppc_icp *icp;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u16 src;
+
+ if (!xics)
+ return -ENODEV;
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ return -EINVAL;
+ state = &ics->irq_state[src];
+
+ icp = kvmppc_xics_find_server(kvm, state->server);
+ if (!icp)
+ return -EINVAL;
+
+ if (write_xive(xics, ics, state, state->server, state->saved_priority,
+ state->saved_priority))
+ icp_deliver_irq(xics, icp, irq);
+
+ return 0;
+}
+
+int kvmppc_xics_int_off(struct kvm *kvm, u32 irq)
+{
+ struct kvmppc_xics *xics = kvm->arch.xics;
+ struct kvmppc_ics *ics;
+ struct ics_irq_state *state;
+ u16 src;
+
+ if (!xics)
+ return -ENODEV;
+
+ ics = kvmppc_xics_find_ics(xics, irq, &src);
+ if (!ics)
+ return -EINVAL;
+ state = &ics->irq_state[src];
+
+ write_xive(xics, ics, state, state->server, MASKED, state->priority);
+
+ return 0;
+}
+
/* -- ICP routines, including hcalls -- */

static inline bool icp_try_update(struct kvmppc_icp *icp,
diff --git a/arch/powerpc/kvm/book3s_xics.h b/arch/powerpc/kvm/book3s_xics.h
index c816c5a..e4fdec3 100644
--- a/arch/powerpc/kvm/book3s_xics.h
+++ b/arch/powerpc/kvm/book3s_xics.h
@@ -36,7 +36,7 @@ struct ics_irq_state {
u32 number;
u32 server;
u8 priority;
- u8 saved_priority; /* currently unused */
+ u8 saved_priority;
u8 resend;
u8 masked_pending;
u8 asserted; /* Only for LSI */
--
1.7.10.4