Merge tag 'loongarch-kvm-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.10

1. Add ParaVirt IPI support.
2. Add software breakpoint support.
3. Add mmio trace events support.

3 files changed, 38 insertions, 21 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 38b498669ef9..38694f95bb56 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -798,8 +798,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 	 * mn_active_invalidate_count (see above) instead of
 	 * mmu_invalidate_in_progress.
 	 */
-	gfn_to_pfn_cache_invalidate_start(kvm, range->start, range->end,
-					  hva_range.may_block);
+	gfn_to_pfn_cache_invalidate_start(kvm, range->start, range->end);
 
 	/*
 	 * If one or more memslots were found and thus zapped, notify arch code
diff --git a/virt/kvm/kvm_mm.h b/virt/kvm/kvm_mm.h
index ecefc7ec51af..715f19669d01 100644
--- a/virt/kvm/kvm_mm.h
+++ b/virt/kvm/kvm_mm.h
@@ -26,13 +26,11 @@ kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool interruptible,
 #ifdef CONFIG_HAVE_KVM_PFNCACHE
 void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm,
 				       unsigned long start,
-				       unsigned long end,
-				       bool may_block);
+				       unsigned long end);
 #else
 static inline void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm,
 						     unsigned long start,
-						     unsigned long end,
-						     bool may_block)
+						     unsigned long end)
 {
 }
 #endif /* HAVE_KVM_PFNCACHE */
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
index 4e07112a24c2..e3453e869e92 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -23,7 +23,7 @@
  * MMU notifier 'invalidate_range_start' hook.
  */
 void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm, unsigned long start,
-				       unsigned long end, bool may_block)
+				       unsigned long end)
 {
 	struct gfn_to_pfn_cache *gpc;
 
@@ -57,6 +57,19 @@ void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm, unsigned long start,
 	spin_unlock(&kvm->gpc_lock);
 }
 
+static bool kvm_gpc_is_valid_len(gpa_t gpa, unsigned long uhva,
+				 unsigned long len)
+{
+	unsigned long offset = kvm_is_error_gpa(gpa) ? offset_in_page(uhva) :
+						       offset_in_page(gpa);
+
+	/*
+	 * The cached access must fit within a single page. The 'len' argument
+	 * to activate() and refresh() exists only to enforce that.
+	 */
+	return offset + len <= PAGE_SIZE;
+}
+
 bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsigned long len)
 {
 	struct kvm_memslots *slots = kvm_memslots(gpc->kvm);
@@ -74,7 +87,7 @@ bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsigned long len)
 	if (kvm_is_error_hva(gpc->uhva))
 		return false;
 
-	if (offset_in_page(gpc->uhva) + len > PAGE_SIZE)
+	if (!kvm_gpc_is_valid_len(gpc->gpa, gpc->uhva, len))
 		return false;
 
 	if (!gpc->valid)
@@ -232,8 +245,7 @@ out_error:
 	return -EFAULT;
 }
 
-static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long uhva,
-			     unsigned long len)
+static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long uhva)
 {
 	unsigned long page_offset;
 	bool unmap_old = false;
@@ -247,15 +259,6 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned l
 	if (WARN_ON_ONCE(kvm_is_error_gpa(gpa) == kvm_is_error_hva(uhva)))
 		return -EINVAL;
 
-	/*
-	 * The cached acces must fit within a single page. The 'len' argument
-	 * exists only to enforce that.
-	 */
-	page_offset = kvm_is_error_gpa(gpa) ? offset_in_page(uhva) :
-					      offset_in_page(gpa);
-	if (page_offset + len > PAGE_SIZE)
-		return -EINVAL;
-
 	lockdep_assert_held(&gpc->refresh_lock);
 
 	write_lock_irq(&gpc->lock);
@@ -270,6 +273,8 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned l
 	old_uhva = PAGE_ALIGN_DOWN(gpc->uhva);
 
 	if (kvm_is_error_gpa(gpa)) {
+		page_offset = offset_in_page(uhva);
+
 		gpc->gpa = INVALID_GPA;
 		gpc->memslot = NULL;
 		gpc->uhva = PAGE_ALIGN_DOWN(uhva);
@@ -279,6 +284,8 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned l
 	} else {
 		struct kvm_memslots *slots = kvm_memslots(gpc->kvm);
 
+		page_offset = offset_in_page(gpa);
+
 		if (gpc->gpa != gpa || gpc->generation != slots->generation ||
 		    kvm_is_error_hva(gpc->uhva)) {
 			gfn_t gfn = gpa_to_gfn(gpa);
@@ -354,6 +361,9 @@ int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, unsigned long len)
 
 	guard(mutex)(&gpc->refresh_lock);
 
+	if (!kvm_gpc_is_valid_len(gpc->gpa, gpc->uhva, len))
+		return -EINVAL;
+
 	/*
 	 * If the GPA is valid then ignore the HVA, as a cache can be GPA-based
 	 * or HVA-based, not both.  For GPA-based caches, the HVA will be
@@ -361,7 +371,7 @@ int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, unsigned long len)
 	 */
 	uhva = kvm_is_error_gpa(gpc->gpa) ? gpc->uhva : KVM_HVA_ERR_BAD;
 
-	return __kvm_gpc_refresh(gpc, gpc->gpa, uhva, len);
+	return __kvm_gpc_refresh(gpc, gpc->gpa, uhva);
 }
 
 void kvm_gpc_init(struct gfn_to_pfn_cache *gpc, struct kvm *kvm)
@@ -381,6 +391,9 @@ static int __kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned
 {
 	struct kvm *kvm = gpc->kvm;
 
+	if (!kvm_gpc_is_valid_len(gpa, uhva, len))
+		return -EINVAL;
+
 	guard(mutex)(&gpc->refresh_lock);
 
 	if (!gpc->active) {
@@ -400,11 +413,18 @@ static int __kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned
 		gpc->active = true;
 		write_unlock_irq(&gpc->lock);
 	}
-	return __kvm_gpc_refresh(gpc, gpa, uhva, len);
+	return __kvm_gpc_refresh(gpc, gpa, uhva);
 }
 
 int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len)
 {
+	/*
+	 * Explicitly disallow INVALID_GPA so that the magic value can be used
+	 * by KVM to differentiate between GPA-based and HVA-based caches.
+	 */
+	if (WARN_ON_ONCE(kvm_is_error_gpa(gpa)))
+		return -EINVAL;
+
 	return __kvm_gpc_activate(gpc, gpa, KVM_HVA_ERR_BAD, len);
 }