Commit eff484e0 authored by Eric Auger's avatar Eric Auger Committed by Christoffer Dall
Browse files

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: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarChristoffer Dall <cdall@linaro.org>
parent 57a9a117

virt/kvm/arm/vgic/vgic-its.c

+113 −3
Original line number Diff line number Diff line
@@ -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 @@ static int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, 
	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;

}



/**

virt/kvm/arm/vgic/vgic.h

+4 −0
Original line number Diff line number Diff line
@@ -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