[PATCH 14/17] kvm/ppc/mpic: add KVM_CAP_IRQ_MPIC

Alexander Graf
2013-04-18T14:11:54Z

From: Scott Wood <scottwood@freescale.com>

Enabling this capability connects the vcpu to the designated in-kernel
MPIC. Using explicit connections between vcpus and irqchips allows
for flexibility, but the main benefit at the moment is that it
simplifies the code -- KVM doesn't need vm-global state to remember
which MPIC object is associated with this vm, and it doesn't need to
care about ordering between irqchip creation and vcpu creation.

Signed-off-by: Scott Wood <scottwood@freescale.com>
[agraf: add stub functions for kvmppc_mpic_{dis,}connect_vcpu]
Signed-off-by: Alexander Graf <agraf@suse.de>
---
Documentation/virtual/kvm/api.txt | 8 +++
arch/powerpc/include/asm/kvm_host.h | 9 ++++
arch/powerpc/include/asm/kvm_ppc.h | 15 ++++++-
arch/powerpc/kvm/booke.c | 4 ++
arch/powerpc/kvm/mpic.c | 82 ++++++++++++++++++++++++++++++++---
arch/powerpc/kvm/powerpc.c | 30 +++++++++++++
include/uapi/linux/kvm.h | 1 +
7 files changed, 141 insertions(+), 8 deletions(-)

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index d52f3f9..4c326ae 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2728,3 +2728,11 @@ to receive the topmost interrupt vector.
When disabled (args[0] = 0), behavior is as if this facility is unsupported.

When this capability is enabled, KVM_EXIT_EPR can occur.
+
+6.6 KVM_CAP_IRQ_MPIC
+
+Architectures: ppc
+Parameters: args[0] is the MPIC device fd
+ args[1] is the MPIC CPU number for this vcpu
+
+This capability connects the vcpu to an in-kernel MPIC device.
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 7e7aef9..36368c9 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -375,6 +375,11 @@ struct kvmppc_booke_debug_reg {
u64 dac[KVMPPC_BOOKE_MAX_DAC];
};

+#define KVMPPC_IRQ_DEFAULT 0
+#define KVMPPC_IRQ_MPIC 1
+
+struct openpic;
+
struct kvm_vcpu_arch {
ulong host_stack;
u32 host_pid;
@@ -554,6 +559,10 @@ struct kvm_vcpu_arch {
unsigned long magic_page_pa; /* phys addr to map the magic page to */
unsigned long magic_page_ea; /* effect. addr to map the magic page to */

+ int irq_type; /* one of KVM_IRQ_* */
+ int irq_cpu_id;
+ struct openpic *mpic; /* KVM_IRQ_MPIC */
+
#ifdef CONFIG_KVM_BOOK3S_64_HV
struct kvm_vcpu_arch_shared shregs;

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 0b86604..c9d9faf 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -248,7 +248,6 @@ int kvmppc_set_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *);
void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 pid);

struct openpic;
-void kvmppc_mpic_put(struct openpic *opp);

#ifdef CONFIG_KVM_BOOK3S_64_HV
static inline void kvmppc_set_xics_phys(int cpu, unsigned long addr)
@@ -278,6 +277,9 @@ static inline void kvmppc_set_epr(struct kvm_vcpu *vcpu, u32 epr)
#ifdef CONFIG_KVM_MPIC

void kvmppc_mpic_set_epr(struct kvm_vcpu *vcpu);
+int kvmppc_mpic_connect_vcpu(struct kvm_device *dev, struct kvm_vcpu *vcpu,
+ u32 cpu);
+void kvmppc_mpic_disconnect_vcpu(struct openpic *opp, struct kvm_vcpu *vcpu);

#else

@@ -285,6 +287,17 @@ static inline void kvmppc_mpic_set_epr(struct kvm_vcpu *vcpu)
{
}

+static inline int kvmppc_mpic_connect_vcpu(struct kvm_device *dev,
+ struct kvm_vcpu *vcpu, u32 cpu)
+{
+ return -EINVAL;
+}
+
+static inline void kvmppc_mpic_disconnect_vcpu(struct openpic *opp,
+ struct kvm_vcpu *vcpu)
+{
+}
+
#endif /* CONFIG_KVM_MPIC */

int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index cff53d4..0097912 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -430,6 +430,10 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu,
if (update_epr = true) {
if (vcpu->arch.epr_flags & KVMPPC_EPR_USER)
kvm_make_request(KVM_REQ_EPR_EXIT, vcpu);
+ else if (vcpu->arch.epr_flags & KVMPPC_EPR_KERNEL) {
+ BUG_ON(vcpu->arch.irq_type != KVMPPC_IRQ_MPIC);
+ kvmppc_mpic_set_epr(vcpu);
+ }
}

new_msr &= msr_mask;
diff --git a/arch/powerpc/kvm/mpic.c b/arch/powerpc/kvm/mpic.c
index 60857d5..b1ae02d 100644
--- a/arch/powerpc/kvm/mpic.c
+++ b/arch/powerpc/kvm/mpic.c
@@ -115,7 +115,7 @@ static int get_current_cpu(void)
{
#if defined(CONFIG_KVM) && defined(CONFIG_BOOKE)
struct kvm_vcpu *vcpu = current->thread.kvm_vcpu;
- return vcpu ? vcpu->vcpu_id : -1;
+ return vcpu ? vcpu->arch.irq_cpu_id : -1;
#else
/* XXX */
return -1;
@@ -249,7 +249,7 @@ static void mpic_irq_raise(struct openpic *opp, struct irq_dest *dst,
return;
}

- pr_debug("%s: cpu %d output %d\n", __func__, dst->vcpu->vcpu_id,
+ pr_debug("%s: cpu %d output %d\n", __func__, dst->vcpu->arch.irq_cpu_id,
output);

if (output != ILR_INTTGT_INT) /* TODO */
@@ -267,7 +267,7 @@ static void mpic_irq_lower(struct openpic *opp, struct irq_dest *dst,
return;
}

- pr_debug("%s: cpu %d output %d\n", __func__, dst->vcpu->vcpu_id,
+ pr_debug("%s: cpu %d output %d\n", __func__, dst->vcpu->arch.irq_cpu_id,
output);

if (output != ILR_INTTGT_INT) /* TODO */
@@ -1165,6 +1165,20 @@ static uint32_t openpic_iack(struct openpic *opp, struct irq_dest *dst,
return retval;
}

+void kvmppc_mpic_set_epr(struct kvm_vcpu *vcpu)
+{
+ struct openpic *opp = vcpu->arch.mpic;
+ int cpu = vcpu->arch.irq_cpu_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&opp->lock, flags);
+
+ if ((opp->gcr & opp->mpic_mode_mask) = GCR_MODE_PROXY)
+ kvmppc_set_epr(vcpu, openpic_iack(opp, &opp->dst[cpu], cpu));
+
+ spin_unlock_irqrestore(&opp->lock, flags);
+}
+
static int openpic_cpu_read_internal(void *opaque, gpa_t addr,
u32 *ptr, int idx)
{
@@ -1431,10 +1445,10 @@ static void map_mmio(struct openpic *opp)

static void unmap_mmio(struct openpic *opp)
{
- BUG_ON(opp->mmio_mapped);
- opp->mmio_mapped = false;
-
- kvm_io_bus_unregister_dev(opp->kvm, KVM_MMIO_BUS, &opp->mmio);
+ if (opp->mmio_mapped) {
+ opp->mmio_mapped = false;
+ kvm_io_bus_unregister_dev(opp->kvm, KVM_MMIO_BUS, &opp->mmio);
+ }
}

static int set_base_addr(struct openpic *opp, struct kvm_device_attr *attr)
@@ -1693,3 +1707,57 @@ struct kvm_device_ops kvm_mpic_ops = {
.get_attr = mpic_get_attr,
.has_attr = mpic_has_attr,
};
+
+int kvmppc_mpic_connect_vcpu(struct kvm_device *dev, struct kvm_vcpu *vcpu,
+ u32 cpu)
+{
+ struct openpic *opp = dev->private;
+ int ret = 0;
+
+ if (dev->ops != &kvm_mpic_ops)
+ return -EPERM;
+ if (opp->kvm != vcpu->kvm)
+ return -EPERM;
+ if (cpu < 0 || cpu >= MAX_CPU)
+ return -EPERM;
+
+ spin_lock_irq(&opp->lock);
+
+ if (opp->dst[cpu].vcpu) {
+ ret = -EEXIST;
+ goto out;
+ }
+ if (vcpu->arch.irq_type) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ opp->dst[cpu].vcpu = vcpu;
+ opp->nb_cpus = max(opp->nb_cpus, cpu + 1);
+
+ vcpu->arch.mpic = opp;
+ vcpu->arch.irq_cpu_id = cpu;
+ vcpu->arch.irq_type = KVMPPC_IRQ_MPIC;
+
+ /* This might need to be changed if GCR gets extended */
+ if (opp->mpic_mode_mask = GCR_MODE_PROXY)
+ vcpu->arch.epr_flags |= KVMPPC_EPR_KERNEL;
+
+ kvm_device_get(dev);
+out:
+ spin_unlock_irq(&opp->lock);
+ return ret;
+}
+
+/*
+ * This should only happen immediately before the mpic is destroyed,
+ * so we shouldn't need to worry about anything still trying to
+ * access the vcpu pointer.
+ */
+void kvmppc_mpic_disconnect_vcpu(struct openpic *opp, struct kvm_vcpu *vcpu)
+{
+ BUG_ON(!opp->dst[vcpu->arch.irq_cpu_id].vcpu);
+
+ opp->dst[vcpu->arch.irq_cpu_id].vcpu = NULL;
+ kvm_device_put(opp->dev);
+}
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 3cad714..c431fea 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -25,6 +25,7 @@
#include <linux/hrtimer.h>
#include <linux/fs.h>
#include <linux/slab.h>
+#include <linux/file.h>
#include <asm/cputable.h>
#include <asm/uaccess.h>
#include <asm/kvm_ppc.h>
@@ -327,6 +328,9 @@ int kvm_dev_ioctl_check_extension(long ext)
#if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC)
case KVM_CAP_SW_TLB:
#endif
+#ifdef CONFIG_KVM_MPIC
+ case KVM_CAP_IRQ_MPIC:
+#endif
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
@@ -460,6 +464,13 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
tasklet_kill(&vcpu->arch.tasklet);

kvmppc_remove_vcpu_debugfs(vcpu);
+
+ switch (vcpu->arch.irq_type) {
+ case KVMPPC_IRQ_MPIC:
+ kvmppc_mpic_disconnect_vcpu(vcpu->arch.mpic, vcpu);
+ break;
+ }
+
kvmppc_core_vcpu_free(vcpu);
}

@@ -793,6 +804,25 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
break;
}
#endif
+#ifdef CONFIG_KVM_MPIC
+ case KVM_CAP_IRQ_MPIC: {
+ struct file *filp;
+ struct kvm_device *dev;
+
+ r = -EBADF;
+ filp = fget(cap->args[0]);
+ if (!filp)
+ break;
+
+ r = -EPERM;
+ dev = kvm_device_from_filp(filp);
+ if (dev)
+ r = kvmppc_mpic_connect_vcpu(dev, vcpu, cap->args[1]);
+
+ fput(filp);
+ break;
+ }
+#endif
default:
r = -EINVAL;
break;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 568d65d..8f95cac 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -667,6 +667,7 @@ struct kvm_ppc_smmu_info {
#define KVM_CAP_ARM_PSCI 87
#define KVM_CAP_ARM_SET_DEVICE_ADDR 88
#define KVM_CAP_DEVICE_CTRL 89
+#define KVM_CAP_IRQ_MPIC 90

#ifdef KVM_CAP_IRQ_ROUTING

--
1.6.0.2