KVM: arm/arm64: Adapt vgic_v3_check_base to multiple rdist regions

vgic_v3_check_base() currently only handles the case of a unique legacy redistributor region whose size is not explicitly set but inferred, instead, from the number of online vcpus. We adapt it to handle the case of multiple redistributor regions with explicitly defined size. We rely on two new helpers: - vgic_v3_rdist_overlap() is used to detect overlap with the dist region if defined - vgic_v3_rd_region_size computes the size of the redist region, would it be a legacy unique region or a new explicitly sized region. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

KVM: arm/arm64: Adapt vgic_v3_check_base to multiple rdist regions
vgic_v3_check_base() currently only handles the case of a unique legacy redistributor region whose size is not explicitly set but inferred, instead, from the number of online vcpus. We adapt it to handle the case of multiple redistributor regions with explicitly defined size. We rely on two new helpers: - vgic_v3_rdist_overlap() is used to detect overlap with the dist region if defined - vgic_v3_rd_region_size computes the size of the redist region, would it be a legacy unique region or a new explicitly sized region. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Eric Auger · Marc Zyngier
1 parent ba7b3f1275
Showing 2 changed files with 42 additions and 17 deletions Side-by-side Diff
virt/kvm/arm/vgic/vgic-v3.c
virt/kvm/arm/vgic/vgic.h
@@ -419,6 +419,29 @@
 	return 0;
 }
  
+/**
+ * vgic_v3_rdist_overlap - check if a region overlaps with any
+ * existing redistributor region
+ *
+ * @kvm: kvm handle
+ * @base: base of the region
+ * @size: size of region
+ *
+ * Return: true if there is an overlap
+ */
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
+{
+	struct vgic_dist *d = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
+
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if ((base + size > rdreg->base) &&
+			(base < rdreg->base + vgic_v3_rd_region_size(kvm, rdreg)))
+			return true;
+	}
+	return false;
+}
+
 /*
  * Check for overlapping regions and for regions crossing the end of memory
  * for base addresses which have already been set.
  
  
  
  
@@ -426,31 +449,23 @@
 bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
-	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
-	struct vgic_redist_region *rdreg =
-		list_first_entry(&d->rd_regions,
-				 struct vgic_redist_region, list);
+	struct vgic_redist_region *rdreg;
  
-	redist_size *= atomic_read(&kvm->online_vcpus);
-
 	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
  
-	if (rdreg && (rdreg->base + redist_size < rdreg->base))
-		return false;
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
+			rdreg->base)
+			return false;
+	}
  
-	/* Both base addresses must be set to check if they overlap */
-	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) || !rdreg)
+	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
 		return true;
  
-	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
-		return true;
-
-	if (rdreg->base + redist_size <= d->vgic_dist_base)
-		return true;
-
-	return false;
+	return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
+				      KVM_VGIC_V3_DIST_SIZE);
 }
  
 /**
@@ -276,6 +276,16 @@
  
 struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
  
+static inline size_t
+vgic_v3_rd_region_size(struct kvm *kvm, struct vgic_redist_region *rdreg)
+{
+	if (!rdreg->count)
+		return atomic_read(&kvm->online_vcpus) * KVM_VGIC_V3_REDIST_SIZE;
+	else
+		return rdreg->count * KVM_VGIC_V3_REDIST_SIZE;
+}
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size);
+
 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);
...	...	@@ -419,6 +419,29 @@
419	419	return 0;
420	420	}
421	421
	422	+/**
	423	+ * vgic_v3_rdist_overlap - check if a region overlaps with any
	424	+ * existing redistributor region
	425	+ *
	426	+ * @kvm: kvm handle
	427	+ * @base: base of the region
	428	+ * @size: size of region
	429	+ *
	430	+ * Return: true if there is an overlap
	431	+ */
	432	+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
	433	+{
	434	+ struct vgic_dist *d = &kvm->arch.vgic;
	435	+ struct vgic_redist_region *rdreg;
	436	+
	437	+ list_for_each_entry(rdreg, &d->rd_regions, list) {
	438	+ if ((base + size > rdreg->base) &&
	439	+ (base < rdreg->base + vgic_v3_rd_region_size(kvm, rdreg)))
	440	+ return true;
	441	+ }
	442	+ return false;
	443	+}
	444	+
422	445	/*
423	446	* Check for overlapping regions and for regions crossing the end of memory
424	447	* for base addresses which have already been set.
425	448
426	449
427	450
428	451
...	...	@@ -426,31 +449,23 @@
426	449	bool vgic_v3_check_base(struct kvm *kvm)
427	450	{
428	451	struct vgic_dist *d = &kvm->arch.vgic;
429		- gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
430		- struct vgic_redist_region *rdreg =
431		- list_first_entry(&d->rd_regions,
432		- struct vgic_redist_region, list);
	452	+ struct vgic_redist_region *rdreg;
433	453
434		- redist_size *= atomic_read(&kvm->online_vcpus);
435		-
436	454	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
437	455	d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
438	456	return false;
439	457
440		- if (rdreg && (rdreg->base + redist_size < rdreg->base))
441		- return false;
	458	+ list_for_each_entry(rdreg, &d->rd_regions, list) {
	459	+ if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
	460	+ rdreg->base)
	461	+ return false;
	462	+ }
442	463
443		- /* Both base addresses must be set to check if they overlap */
444		- if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) \|\| !rdreg)
	464	+ if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
445	465	return true;
446	466
447		- if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
448		- return true;
449		-
450		- if (rdreg->base + redist_size <= d->vgic_dist_base)
451		- return true;
452		-
453		- return false;
	467	+ return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
	468	+ KVM_VGIC_V3_DIST_SIZE);
454	469	}
455	470
456	471	/**
...	...	@@ -276,6 +276,16 @@
276	276
277	277	struct vgic_redist_region vgic_v3_rdist_free_slot(struct list_head rdregs);
278	278
	279	+static inline size_t
	280	+vgic_v3_rd_region_size(struct kvm kvm, struct vgic_redist_region rdreg)
	281	+{
	282	+ if (!rdreg->count)
	283	+ return atomic_read(&kvm->online_vcpus) * KVM_VGIC_V3_REDIST_SIZE;
	284	+ else
	285	+ return rdreg->count * KVM_VGIC_V3_REDIST_SIZE;
	286	+}
	287	+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size);
	288	+
279	289	int vgic_its_resolve_lpi(struct kvm kvm, struct vgic_its its,
280	290	u32 devid, u32 eventid, struct vgic_irq **irq);
281	291	struct vgic_its vgic_msi_to_its(struct kvm kvm, struct kvm_msi *msi);