[PATCH v3 06/15] KVM: Refactor hva based memory invalidation code

[Chao Peng <chao.p.peng@linux.intel.com>]

The purpose of this patch is for fd-based memslot to reuse the same
mmu_notifier based guest memory invalidation code for private pages.

No functional changes except renaming 'hva' to more neutral 'useraddr'
so that it can also cover 'offset' in a fd that private pages live in.

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
---
 include/linux/kvm_host.h |  8 +++++--
 virt/kvm/kvm_main.c      | 47 +++++++++++++++++++++-------------------
 2 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index b0b63c9a160f..7279f46f35d3 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1327,9 +1327,13 @@ static inline int memslot_id(struct kvm *kvm, gfn_t gfn)
 }
 
 static inline gfn_t
-hva_to_gfn_memslot(unsigned long hva, struct kvm_memory_slot *slot)
+useraddr_to_gfn_memslot(unsigned long useraddr, struct kvm_memory_slot *slot,
+			bool addr_is_hva)
 {
-	gfn_t gfn_offset = (hva - slot->userspace_addr) >> PAGE_SHIFT;
+	unsigned long useraddr_base = addr_is_hva ? slot->userspace_addr
+						  : slot->file_ofs;
+
+	gfn_t gfn_offset = (useraddr - useraddr_base) >> PAGE_SHIFT;
 
 	return slot->base_gfn + gfn_offset;
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 68018ee7f0cd..856f89ed8ab5 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -471,16 +471,16 @@ static void kvm_mmu_notifier_invalidate_range(struct mmu_notifier *mn,
 	srcu_read_unlock(&kvm->srcu, idx);
 }
 
-typedef bool (*hva_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range);
+typedef bool (*gfn_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range);
 
 typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start,
 			     unsigned long end);
 
-struct kvm_hva_range {
+struct kvm_useraddr_range {
 	unsigned long start;
 	unsigned long end;
 	pte_t pte;
-	hva_handler_t handler;
+	gfn_handler_t handler;
 	on_lock_fn_t on_lock;
 	bool flush_on_ret;
 	bool may_block;
@@ -499,8 +499,8 @@ static void kvm_null_fn(void)
 }
 #define IS_KVM_NULL_FN(fn) ((fn) == (void *)kvm_null_fn)
 
-static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
-						  const struct kvm_hva_range *range)
+static __always_inline int __kvm_handle_useraddr_range(struct kvm *kvm,
+					const struct kvm_useraddr_range *range)
 {
 	bool ret = false, locked = false;
 	struct kvm_gfn_range gfn_range;
@@ -518,12 +518,12 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
 	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
 		slots = __kvm_memslots(kvm, i);
 		kvm_for_each_memslot(slot, slots) {
-			unsigned long hva_start, hva_end;
+			unsigned long useraddr_start, useraddr_end;
 
-			hva_start = max(range->start, slot->userspace_addr);
-			hva_end = min(range->end, slot->userspace_addr +
+			useraddr_start = max(range->start, slot->userspace_addr);
+			useraddr_end = min(range->end, slot->userspace_addr +
 						  (slot->npages << PAGE_SHIFT));
-			if (hva_start >= hva_end)
+			if (useraddr_start >= useraddr_end)
 				continue;
 
 			/*
@@ -536,11 +536,14 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
 			gfn_range.may_block = range->may_block;
 
 			/*
-			 * {gfn(page) | page intersects with [hva_start, hva_end)} =
+			 * {gfn(page) | page intersects with [useraddr_start, useraddr_end)} =
 			 * {gfn_start, gfn_start+1, ..., gfn_end-1}.
 			 */
-			gfn_range.start = hva_to_gfn_memslot(hva_start, slot);
-			gfn_range.end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, slot);
+			gfn_range.start = useraddr_to_gfn_memslot(useraddr_start,
+								  slot, true);
+			gfn_range.end = useraddr_to_gfn_memslot(
+						useraddr_end + PAGE_SIZE - 1,
+						slot, true);
 			gfn_range.slot = slot;
 
 			if (!locked) {
@@ -571,10 +574,10 @@ static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn,
 						unsigned long start,
 						unsigned long end,
 						pte_t pte,
-						hva_handler_t handler)
+						gfn_handler_t handler)
 {
 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
-	const struct kvm_hva_range range = {
+	const struct kvm_useraddr_range range = {
 		.start		= start,
 		.end		= end,
 		.pte		= pte,
@@ -584,16 +587,16 @@ static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn,
 		.may_block	= false,
 	};
 
-	return __kvm_handle_hva_range(kvm, &range);
+	return __kvm_handle_useraddr_range(kvm, &range);
 }
 
 static __always_inline int kvm_handle_hva_range_no_flush(struct mmu_notifier *mn,
 							 unsigned long start,
 							 unsigned long end,
-							 hva_handler_t handler)
+							 gfn_handler_t handler)
 {
 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
-	const struct kvm_hva_range range = {
+	const struct kvm_useraddr_range range = {
 		.start		= start,
 		.end		= end,
 		.pte		= __pte(0),
@@ -603,7 +606,7 @@ static __always_inline int kvm_handle_hva_range_no_flush(struct mmu_notifier *mn
 		.may_block	= false,
 	};
 
-	return __kvm_handle_hva_range(kvm, &range);
+	return __kvm_handle_useraddr_range(kvm, &range);
 }
 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 					struct mm_struct *mm,
@@ -661,7 +664,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 					const struct mmu_notifier_range *range)
 {
 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
-	const struct kvm_hva_range hva_range = {
+	const struct kvm_useraddr_range useraddr_range = {
 		.start		= range->start,
 		.end		= range->end,
 		.pte		= __pte(0),
@@ -685,7 +688,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 	kvm->mn_active_invalidate_count++;
 	spin_unlock(&kvm->mn_invalidate_lock);
 
-	__kvm_handle_hva_range(kvm, &hva_range);
+	__kvm_handle_useraddr_range(kvm, &useraddr_range);
 
 	return 0;
 }
@@ -712,7 +715,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 					const struct mmu_notifier_range *range)
 {
 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
-	const struct kvm_hva_range hva_range = {
+	const struct kvm_useraddr_range useraddr_range = {
 		.start		= range->start,
 		.end		= range->end,
 		.pte		= __pte(0),
@@ -723,7 +726,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
 	};
 	bool wake;
 
-	__kvm_handle_hva_range(kvm, &hva_range);
+	__kvm_handle_useraddr_range(kvm, &useraddr_range);
 
 	/* Pairs with the increment in range_start(). */
 	spin_lock(&kvm->mn_invalidate_lock);
-- 
2.17.1