[PATCH v3 04/12] KVM: arm/arm64: Helper to locate free rdist index

[Eric Auger]

We introduce vgic_v3_rdist_free_slot to help identifying
where we can place a new 2x64KB redistributor.

Signed-off-by: Eric Auger <eric.au...@redhat.com>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c |  3 +--
 virt/kvm/arm/vgic/vgic-v3.c      | 17 +++++++++++++++++
 virt/kvm/arm/vgic/vgic.h         | 11 +++++++++++
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index d1aab18..49ca176 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -593,8 +593,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
         * function for all VCPUs when the base address is set.  Just return
         * without doing any work for now.
         */
-       rdreg = list_first_entry(&vgic->rd_regions,
-                                struct vgic_redist_region, list);
+       rdreg = vgic_v3_rdist_free_slot(&vgic->rd_regions);
        if (!rdreg)
                return 0;
 
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 94de6cd..820012a 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -444,6 +444,23 @@ bool vgic_v3_check_base(struct kvm *kvm)
        return false;
 }
 
+/**
+ * vgic_v3_rdist_free_slot - Look up registered rdist regions and identify one
+ * which has free space to put a new rdist regions
+ *
+ * If any, return this redist region handle, otherwise returns NULL.
+ */
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head 
*rd_regions)
+{
+       struct vgic_redist_region *rdreg;
+
+       list_for_each_entry(rdreg, rd_regions, list) {
+               if (!vgic_v3_redist_region_full(rdreg))
+                       return rdreg;
+       }
+       return NULL;
+}
+
 int vgic_v3_map_resources(struct kvm *kvm)
 {
        int ret = 0;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 830e815..fea32cb 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -251,6 +251,17 @@ static inline int vgic_v3_max_apr_idx(struct kvm_vcpu 
*vcpu)
        }
 }
 
+static inline bool
+vgic_v3_redist_region_full(struct vgic_redist_region *region)
+{
+       if (!region->count)
+               return false;
+
+       return (region->free_index >= region->count);
+}
+
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
+
 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);
-- 
2.5.5

_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm