[PATCH v2 06/10] KVM: arm/arm64: vgic: Allow dynamic mapping of physical/virtual interrupts
Marc Zyngier
marc.zyngier at arm.com
Wed Jul 8 10:56:38 PDT 2015
In order to be able to feed physical interrupts to a guest, we need
to be able to establish the virtual-physical mapping between the two
worlds.
The mappings are kept in a set of RCU lists, indexed by virtual interrupts.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm/kvm/arm.c | 2 +
include/kvm/arm_vgic.h | 25 +++++++++
virt/kvm/arm/vgic.c | 144 ++++++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 170 insertions(+), 1 deletion(-)
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 1583a34..d5ce5cc 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -125,6 +125,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
if (ret)
goto out_free_stage2_pgd;
+ kvm_vgic_init(kvm);
kvm_timer_init(kvm);
/* Mark the initial VMID generation invalid */
@@ -249,6 +250,7 @@ out:
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
+ kvm_vgic_vcpu_postcreate(vcpu);
}
void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 4f9fa1d..32e57d2 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -159,6 +159,19 @@ struct vgic_io_device {
struct kvm_io_device dev;
};
+struct irq_phys_map {
+ u32 virt_irq;
+ u32 phys_irq;
+ u32 irq;
+ bool active;
+};
+
+struct irq_phys_map_entry {
+ struct list_head entry;
+ struct rcu_head rcu;
+ struct irq_phys_map map;
+};
+
struct vgic_dist {
spinlock_t lock;
bool in_kernel;
@@ -256,6 +269,10 @@ struct vgic_dist {
struct vgic_vm_ops vm_ops;
struct vgic_io_device dist_iodev;
struct vgic_io_device *redist_iodevs;
+
+ /* Virtual irq to hwirq mapping */
+ spinlock_t irq_phys_map_lock;
+ struct list_head irq_phys_map_list;
};
struct vgic_v2_cpu_if {
@@ -307,6 +324,9 @@ struct vgic_cpu {
struct vgic_v2_cpu_if vgic_v2;
struct vgic_v3_cpu_if vgic_v3;
};
+
+ /* Protected by the distributor's irq_phys_map_lock */
+ struct list_head irq_phys_map_list;
};
#define LR_EMPTY 0xff
@@ -321,8 +341,10 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write);
int kvm_vgic_hyp_init(void);
int kvm_vgic_map_resources(struct kvm *kvm);
int kvm_vgic_get_max_vcpus(void);
+void kvm_vgic_init(struct kvm *kvm);
int kvm_vgic_create(struct kvm *kvm, u32 type);
void kvm_vgic_destroy(struct kvm *kvm);
+void kvm_vgic_vcpu_postcreate(struct kvm_vcpu *vcpu);
void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu);
void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu);
void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu);
@@ -331,6 +353,9 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg);
int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu);
+struct irq_phys_map *vgic_map_phys_irq(struct kvm_vcpu *vcpu,
+ int virt_irq, int irq);
+int vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map);
#define irqchip_in_kernel(k) (!!((k)->arch.vgic.in_kernel))
#define vgic_initialized(k) (!!((k)->arch.vgic.nr_cpus))
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 5bd1695..3424329 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -24,6 +24,7 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
+#include <linux/rculist.h>
#include <linux/uaccess.h>
#include <asm/kvm_emulate.h>
@@ -82,6 +83,8 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu);
static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr);
static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc);
+static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu,
+ int virt_irq);
static const struct vgic_ops *vgic_ops;
static const struct vgic_params *vgic;
@@ -1583,6 +1586,131 @@ static irqreturn_t vgic_maintenance_handler(int irq, void *data)
return IRQ_HANDLED;
}
+static struct list_head *vgic_get_irq_phys_map(struct kvm_vcpu *vcpu,
+ int virt_irq)
+{
+ if (virt_irq < VGIC_NR_PRIVATE_IRQS)
+ return &vcpu->arch.vgic_cpu.irq_phys_map_list;
+ else
+ return &vcpu->kvm->arch.vgic.irq_phys_map_list;
+}
+
+struct irq_phys_map *vgic_map_phys_irq(struct kvm_vcpu *vcpu,
+ int virt_irq, int irq)
+{
+ struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+ struct list_head *root = vgic_get_irq_phys_map(vcpu, virt_irq);
+ struct irq_phys_map *map;
+ struct irq_phys_map_entry *entry;
+ struct irq_desc *desc;
+ struct irq_data *data;
+ int phys_irq;
+
+ desc = irq_to_desc(irq);
+ if (!desc) {
+ kvm_err("kvm_arch_timer: can't obtain interrupt descriptor\n");
+ return NULL;
+ }
+
+ data = irq_desc_get_irq_data(desc);
+ while (data->parent_data)
+ data = data->parent_data;
+
+ phys_irq = data->hwirq;
+
+ spin_lock(&dist->irq_phys_map_lock);
+
+ /* Try to match an existing mapping */
+ map = vgic_irq_map_search(vcpu, virt_irq);
+ if (map) {
+ /* Make sure this mapping matches */
+ if (map->phys_irq != phys_irq ||
+ map->irq != irq)
+ map = NULL;
+
+ goto out;
+ }
+
+ /* Create a new mapping */
+ entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
+ if (!entry)
+ goto out;
+
+ map = &entry->map;
+ map->virt_irq = virt_irq;
+ map->phys_irq = phys_irq;
+ map->irq = irq;
+
+ list_add_tail_rcu(&entry->entry, root);
+
+out:
+ spin_unlock(&dist->irq_phys_map_lock);
+ return map;
+}
+
+static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu,
+ int virt_irq)
+{
+ struct list_head *root = vgic_get_irq_phys_map(vcpu, virt_irq);
+ struct irq_phys_map_entry *entry;
+ struct irq_phys_map *map;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, root, entry) {
+ map = &entry->map;
+ if (map->virt_irq == virt_irq) {
+ rcu_read_unlock();
+ return map;
+ }
+ }
+
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu)
+{
+ struct irq_phys_map_entry *entry;
+
+ entry = container_of(rcu, struct irq_phys_map_entry, rcu);
+ kfree(entry);
+}
+
+int vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map)
+{
+ struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+ struct irq_phys_map_entry *entry;
+
+ if (!map)
+ return -EINVAL;
+
+ entry = container_of(map, struct irq_phys_map_entry, map);
+
+ spin_lock(&dist->irq_phys_map_lock);
+ list_del_rcu(&entry->entry);
+ call_rcu(&entry->rcu, vgic_free_phys_irq_map_rcu);
+ spin_unlock(&dist->irq_phys_map_lock);
+
+ return 0;
+}
+
+static void vgic_destroy_irq_phys_map(struct kvm *kvm, struct list_head *root)
+{
+ struct vgic_dist *dist = &kvm->arch.vgic;
+ struct irq_phys_map_entry *entry;
+
+ spin_lock(&dist->irq_phys_map_lock);
+
+ list_for_each_entry(entry, root, entry) {
+ list_del_rcu(&entry->entry);
+ call_rcu(&entry->rcu, vgic_free_phys_irq_map_rcu);
+ }
+
+ spin_unlock(&dist->irq_phys_map_lock);
+}
+
void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
@@ -1591,6 +1719,7 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
kfree(vgic_cpu->active_shared);
kfree(vgic_cpu->pend_act_shared);
kfree(vgic_cpu->vgic_irq_lr_map);
+ vgic_destroy_irq_phys_map(vcpu->kvm, &vgic_cpu->irq_phys_map_list);
vgic_cpu->pending_shared = NULL;
vgic_cpu->active_shared = NULL;
vgic_cpu->pend_act_shared = NULL;
@@ -1627,6 +1756,12 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
return 0;
}
+void kvm_vgic_vcpu_postcreate(struct kvm_vcpu *vcpu)
+{
+ struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+ INIT_LIST_HEAD(&vgic_cpu->irq_phys_map_list);
+}
+
/**
* kvm_vgic_get_max_vcpus - Get the maximum number of VCPUs allowed by HW
*
@@ -1664,6 +1799,7 @@ void kvm_vgic_destroy(struct kvm *kvm)
kfree(dist->irq_spi_target);
kfree(dist->irq_pending_on_cpu);
kfree(dist->irq_active_on_cpu);
+ vgic_destroy_irq_phys_map(kvm, &dist->irq_phys_map_list);
dist->irq_sgi_sources = NULL;
dist->irq_spi_cpu = NULL;
dist->irq_spi_target = NULL;
@@ -1787,6 +1923,13 @@ static int init_vgic_model(struct kvm *kvm, int type)
return 0;
}
+void kvm_vgic_init(struct kvm *kvm)
+{
+ spin_lock_init(&kvm->arch.vgic.lock);
+ spin_lock_init(&kvm->arch.vgic.irq_phys_map_lock);
+ INIT_LIST_HEAD(&kvm->arch.vgic.irq_phys_map_list);
+}
+
int kvm_vgic_create(struct kvm *kvm, u32 type)
{
int i, vcpu_lock_idx = -1, ret;
@@ -1832,7 +1975,6 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
if (ret)
goto out_unlock;
- spin_lock_init(&kvm->arch.vgic.lock);
kvm->arch.vgic.in_kernel = true;
kvm->arch.vgic.vgic_model = type;
kvm->arch.vgic.vctrl_base = vgic->vctrl_base;
--
2.1.4
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