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Diffstat (limited to 'arch/arm64/kvm/vgic/vgic.c')
-rw-r--r--arch/arm64/kvm/vgic/vgic.c62
1 files changed, 22 insertions, 40 deletions
diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c
index db2a95762b..4ec93587c8 100644
--- a/arch/arm64/kvm/vgic/vgic.c
+++ b/arch/arm64/kvm/vgic/vgic.c
@@ -30,7 +30,8 @@ struct vgic_global kvm_vgic_global_state __ro_after_init = {
* its->its_lock (mutex)
* vgic_cpu->ap_list_lock must be taken with IRQs disabled
* kvm->lpi_list_lock must be taken with IRQs disabled
- * vgic_irq->irq_lock must be taken with IRQs disabled
+ * vgic_dist->lpi_xa.xa_lock must be taken with IRQs disabled
+ * vgic_irq->irq_lock must be taken with IRQs disabled
*
* As the ap_list_lock might be taken from the timer interrupt handler,
* we have to disable IRQs before taking this lock and everything lower
@@ -54,32 +55,22 @@ struct vgic_global kvm_vgic_global_state __ro_after_init = {
*/
/*
- * Iterate over the VM's list of mapped LPIs to find the one with a
- * matching interrupt ID and return a reference to the IRQ structure.
+ * Index the VM's xarray of mapped LPIs and return a reference to the IRQ
+ * structure. The caller is expected to call vgic_put_irq() later once it's
+ * finished with the IRQ.
*/
static struct vgic_irq *vgic_get_lpi(struct kvm *kvm, u32 intid)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_irq *irq = NULL;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
- list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
- if (irq->intid != intid)
- continue;
+ rcu_read_lock();
- /*
- * This increases the refcount, the caller is expected to
- * call vgic_put_irq() later once it's finished with the IRQ.
- */
- vgic_get_irq_kref(irq);
- goto out_unlock;
- }
- irq = NULL;
+ irq = xa_load(&dist->lpi_xa, intid);
+ if (!vgic_try_get_irq_kref(irq))
+ irq = NULL;
-out_unlock:
- raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
+ rcu_read_unlock();
return irq;
}
@@ -120,22 +111,6 @@ static void vgic_irq_release(struct kref *ref)
{
}
-/*
- * Drop the refcount on the LPI. Must be called with lpi_list_lock held.
- */
-void __vgic_put_lpi_locked(struct kvm *kvm, struct vgic_irq *irq)
-{
- struct vgic_dist *dist = &kvm->arch.vgic;
-
- if (!kref_put(&irq->refcount, vgic_irq_release))
- return;
-
- list_del(&irq->lpi_list);
- dist->lpi_list_count--;
-
- kfree(irq);
-}
-
void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq)
{
struct vgic_dist *dist = &kvm->arch.vgic;
@@ -144,9 +119,15 @@ void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq)
if (irq->intid < VGIC_MIN_LPI)
return;
- raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
- __vgic_put_lpi_locked(kvm, irq);
- raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
+ if (!kref_put(&irq->refcount, vgic_irq_release))
+ return;
+
+ xa_lock_irqsave(&dist->lpi_xa, flags);
+ __xa_erase(&dist->lpi_xa, irq->intid);
+ xa_unlock_irqrestore(&dist->lpi_xa, flags);
+
+ atomic_dec(&dist->lpi_count);
+ kfree_rcu(irq, rcu);
}
void vgic_flush_pending_lpis(struct kvm_vcpu *vcpu)
@@ -203,7 +184,7 @@ void vgic_irq_set_phys_active(struct vgic_irq *irq, bool active)
}
/**
- * kvm_vgic_target_oracle - compute the target vcpu for an irq
+ * vgic_target_oracle - compute the target vcpu for an irq
*
* @irq: The irq to route. Must be already locked.
*
@@ -404,7 +385,8 @@ retry:
/*
* Grab a reference to the irq to reflect the fact that it is
- * now in the ap_list.
+ * now in the ap_list. This is safe as the caller must already hold a
+ * reference on the irq.
*/
vgic_get_irq_kref(irq);
list_add_tail(&irq->ap_list, &vcpu->arch.vgic_cpu.ap_list_head);