KVM: arm64: vgic-its: ITT save and restore

Implement routines to save and restore device ITT and their
interrupt table entries (ITE).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 3dea626400d1bb7b548c460bcdb6a90d77baa336..adb3d9ea72f706648bb966ab1d78bd0660f522e2 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1750,7 +1750,7 @@ static u32 compute_next_devid_offset(struct list_head *h,
        return min_t(u32, next_offset, VITS_DTE_MAX_DEVID_OFFSET);
 }
 
-u32 compute_next_eventid_offset(struct list_head *h, struct its_ite *ite)
+static u32 compute_next_eventid_offset(struct list_head *h, struct its_ite *ite)
 {
        struct its_ite *next;
        u32 next_offset;
@@ -1827,14 +1827,124 @@ out:
        return ret;
 }
 
+/**
+ * vgic_its_save_ite - Save an interrupt translation entry at @gpa
+ */
+static int vgic_its_save_ite(struct vgic_its *its, struct its_device *dev,
+                             struct its_ite *ite, gpa_t gpa, int ite_esz)
+{
+       struct kvm *kvm = its->dev->kvm;
+       u32 next_offset;
+       u64 val;
+
+       next_offset = compute_next_eventid_offset(&dev->itt_head, ite);
+       val = ((u64)next_offset << KVM_ITS_ITE_NEXT_SHIFT) |
+              ((u64)ite->lpi << KVM_ITS_ITE_PINTID_SHIFT) |
+               ite->collection->collection_id;
+       val = cpu_to_le64(val);
+       return kvm_write_guest(kvm, gpa, &val, ite_esz);
+}
+
+/**
+ * vgic_its_restore_ite - restore an interrupt translation entry
+ * @event_id: id used for indexing
+ * @ptr: pointer to the ITE entry
+ * @opaque: pointer to the its_device
+ */
+static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id,
+                               void *ptr, void *opaque)
+{
+       struct its_device *dev = (struct its_device *)opaque;
+       struct its_collection *collection;
+       struct kvm *kvm = its->dev->kvm;
+       struct kvm_vcpu *vcpu = NULL;
+       u64 val;
+       u64 *p = (u64 *)ptr;
+       struct vgic_irq *irq;
+       u32 coll_id, lpi_id;
+       struct its_ite *ite;
+       u32 offset;
+
+       val = *p;
+
+       val = le64_to_cpu(val);
+
+       coll_id = val & KVM_ITS_ITE_ICID_MASK;
+       lpi_id = (val & KVM_ITS_ITE_PINTID_MASK) >> KVM_ITS_ITE_PINTID_SHIFT;
+
+       if (!lpi_id)
+               return 1; /* invalid entry, no choice but to scan next entry */
+
+       if (lpi_id < VGIC_MIN_LPI)
+               return -EINVAL;
+
+       offset = val >> KVM_ITS_ITE_NEXT_SHIFT;
+       if (event_id + offset >= BIT_ULL(dev->num_eventid_bits))
+               return -EINVAL;
+
+       collection = find_collection(its, coll_id);
+       if (!collection)
+               return -EINVAL;
+
+       ite = vgic_its_alloc_ite(dev, collection, lpi_id, event_id);
+       if (IS_ERR(ite))
+               return PTR_ERR(ite);
+
+       if (its_is_collection_mapped(collection))
+               vcpu = kvm_get_vcpu(kvm, collection->target_addr);
+
+       irq = vgic_add_lpi(kvm, lpi_id, vcpu);
+       if (IS_ERR(irq))
+               return PTR_ERR(irq);
+       ite->irq = irq;
+
+       return offset;
+}
+
+static int vgic_its_ite_cmp(void *priv, struct list_head *a,
+                           struct list_head *b)
+{
+       struct its_ite *itea = container_of(a, struct its_ite, ite_list);
+       struct its_ite *iteb = container_of(b, struct its_ite, ite_list);
+
+       if (itea->event_id < iteb->event_id)
+               return -1;
+       else
+               return 1;
+}
+
 static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device)
 {
-       return -ENXIO;
+       const struct vgic_its_abi *abi = vgic_its_get_abi(its);
+       gpa_t base = device->itt_addr;
+       struct its_ite *ite;
+       int ret;
+       int ite_esz = abi->ite_esz;
+
+       list_sort(NULL, &device->itt_head, vgic_its_ite_cmp);
+
+       list_for_each_entry(ite, &device->itt_head, ite_list) {
+               gpa_t gpa = base + ite->event_id * ite_esz;
+
+               ret = vgic_its_save_ite(its, device, ite, gpa, ite_esz);
+               if (ret)
+                       return ret;
+       }
+       return 0;
 }
 
 static int vgic_its_restore_itt(struct vgic_its *its, struct its_device *dev)
 {
-       return -ENXIO;
+       const struct vgic_its_abi *abi = vgic_its_get_abi(its);
+       gpa_t base = dev->itt_addr;
+       int ret;
+       int ite_esz = abi->ite_esz;
+       size_t max_size = BIT_ULL(dev->num_eventid_bits) * ite_esz;
+
+       ret = scan_its_table(its, base, max_size, ite_esz, 0,
+                            vgic_its_restore_ite, dev);
+
+       return ret;
 }
 
 /**

diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index f35e993883dce2e980dc2360963d250f7d44e301..433449b25c785663b928a723aabe67de4627df88 100644 (file)
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -81,6 +81,10 @@
 #define KVM_ITS_CTE_VALID_MASK         BIT_ULL(63)
 #define KVM_ITS_CTE_RDBASE_SHIFT       16
 #define KVM_ITS_CTE_ICID_MASK          GENMASK_ULL(15, 0)
+#define KVM_ITS_ITE_NEXT_SHIFT         48
+#define KVM_ITS_ITE_PINTID_SHIFT       16
+#define KVM_ITS_ITE_PINTID_MASK                GENMASK_ULL(47, 16)
+#define KVM_ITS_ITE_ICID_MASK          GENMASK_ULL(15, 0)
 #define KVM_ITS_DTE_VALID_SHIFT                63
 #define KVM_ITS_DTE_VALID_MASK         BIT_ULL(63)
 #define KVM_ITS_DTE_NEXT_SHIFT         49