KVM: arm64: vgic-its: Get rid of vgic_copy_lpi_list()

The last user has been transitioned to walking the LPI xarray directly.
Cut the wart off, and get rid of the now unneeded lpi_count while doing
so.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-7-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index 5025ac968d27302a31f0dc5b0b4ff99bbaebf8a8..441134ad674e28a7cf378b1b2196235cfaf20074 100644 (file)
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -86,11 +86,8 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
        if (ret) {
                xa_release(&dist->lpi_xa, intid);
                kfree(irq);
-               goto out_unlock;
        }
 
-       atomic_inc(&dist->lpi_count);
-
 out_unlock:
        raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
 
@@ -316,51 +313,6 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
        return 0;
 }
 
-/*
- * Create a snapshot of the current LPIs targeting @vcpu, so that we can
- * enumerate those LPIs without holding any lock.
- * Returns their number and puts the kmalloc'ed array into intid_ptr.
- */
-int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr)
-{
-       struct vgic_dist *dist = &kvm->arch.vgic;
-       XA_STATE(xas, &dist->lpi_xa, GIC_LPI_OFFSET);
-       struct vgic_irq *irq;
-       unsigned long flags;
-       u32 *intids;
-       int irq_count, i = 0;
-
-       /*
-        * There is an obvious race between allocating the array and LPIs
-        * being mapped/unmapped. If we ended up here as a result of a
-        * command, we're safe (locks are held, preventing another
-        * command). If coming from another path (such as enabling LPIs),
-        * we must be careful not to overrun the array.
-        */
-       irq_count = atomic_read(&dist->lpi_count);
-       intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL_ACCOUNT);
-       if (!intids)
-               return -ENOMEM;
-
-       raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
-       rcu_read_lock();
-
-       xas_for_each(&xas, irq, VGIC_LPI_MAX_INTID) {
-               if (i == irq_count)
-                       break;
-               /* We don't need to "get" the IRQ, as we hold the list lock. */
-               if (vcpu && irq->target_vcpu != vcpu)
-                       continue;
-               intids[i++] = irq->intid;
-       }
-
-       rcu_read_unlock();
-       raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
-
-       *intid_ptr = intids;
-       return i;
-}
-
 static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
 {
        int ret = 0;

diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c
index 4ec93587c8cd2b07d11e08efe0614e211c44ef51..e3ee1bc1214af40b4c390c6470a6f45cfc9d9c36 100644 (file)
--- a/arch/arm64/kvm/vgic/vgic.c
+++ b/arch/arm64/kvm/vgic/vgic.c
@@ -126,7 +126,6 @@ void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq)
        __xa_erase(&dist->lpi_xa, irq->intid);
        xa_unlock_irqrestore(&dist->lpi_xa, flags);
 
-       atomic_dec(&dist->lpi_count);
        kfree_rcu(irq, rcu);
 }
 

diff --git a/arch/arm64/kvm/vgic/vgic.h b/arch/arm64/kvm/vgic/vgic.h
index e0c77e1bd9f6b45d16f44040693e409ca006ada3..060dfd96b41fed282b931e3eb750134c24728ed3 100644 (file)
--- a/arch/arm64/kvm/vgic/vgic.h
+++ b/arch/arm64/kvm/vgic/vgic.h
@@ -331,7 +331,6 @@ static inline bool vgic_dist_overlap(struct kvm *kvm, gpa_t base, size_t size)
 }
 
 bool vgic_lpis_enabled(struct kvm_vcpu *vcpu);
-int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr);
 int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
                         u32 devid, u32 eventid, struct vgic_irq **irq);
 struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 8eb72721dac11395c373d73ce54724d3167e4d00..ac7f15ec15869f4502351491f1253a534ac227c6 100644 (file)
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -279,7 +279,6 @@ struct vgic_dist {
 
 #define LPI_XA_MARK_DEBUG_ITER XA_MARK_0
        struct xarray           lpi_xa;
-       atomic_t                lpi_count;
 
        /* LPI translation cache */
        struct list_head        lpi_translation_cache;