KVM: arm64: Pass mm_ops through the visitor context

As a prerequisite for getting visitors off of struct kvm_pgtable, pass
mm_ops through the visitor context.

No functional change intended.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221107215644.1895162-4-oliver.upton@linux.dev

3 files changed, 26 insertions, 41 deletions

diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
index 14d4b68a1e92..a752793482cb 100644
--- a/arch/arm64/include/asm/kvm_pgtable.h
+++ b/arch/arm64/include/asm/kvm_pgtable.h
@@ -203,6 +203,7 @@ struct kvm_pgtable_visit_ctx {
 	kvm_pte_t				*ptep;
 	kvm_pte_t				old;
 	void					*arg;
+	struct kvm_pgtable_mm_ops		*mm_ops;
 	u64					addr;
 	u64					end;
 	u32					level;
diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c
index 6af443c9d78e..1068338d77f3 100644
--- a/arch/arm64/kvm/hyp/nvhe/setup.c
+++ b/arch/arm64/kvm/hyp/nvhe/setup.c
@@ -189,7 +189,7 @@ static void hpool_put_page(void *addr)
 static int finalize_host_mappings_walker(const struct kvm_pgtable_visit_ctx *ctx,
 					 enum kvm_pgtable_walk_flags visit)
 {
-	struct kvm_pgtable_mm_ops *mm_ops = ctx->arg;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 	enum kvm_pgtable_prot prot;
 	enum pkvm_page_state state;
 	phys_addr_t phys;
@@ -239,7 +239,6 @@ static int finalize_host_mappings(void)
 	struct kvm_pgtable_walker walker = {
 		.cb	= finalize_host_mappings_walker,
 		.flags	= KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
-		.arg	= pkvm_pgtable.mm_ops,
 	};
 	int i, ret;
 
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index fb3696b3a997..db25e81a9890 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -181,9 +181,10 @@ static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data,
 }
 
 static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data,
-			      kvm_pte_t *pgtable, u32 level);
+			      struct kvm_pgtable_mm_ops *mm_ops, kvm_pte_t *pgtable, u32 level);
 
 static inline int __kvm_pgtable_visit(struct kvm_pgtable_walk_data *data,
+				      struct kvm_pgtable_mm_ops *mm_ops,
 				      kvm_pte_t *ptep, u32 level)
 {
 	enum kvm_pgtable_walk_flags flags = data->walker->flags;
@@ -191,6 +192,7 @@ static inline int __kvm_pgtable_visit(struct kvm_pgtable_walk_data *data,
 		.ptep	= ptep,
 		.old	= READ_ONCE(*ptep),
 		.arg	= data->walker->arg,
+		.mm_ops	= mm_ops,
 		.addr	= data->addr,
 		.end	= data->end,
 		.level	= level,
@@ -218,8 +220,8 @@ static inline int __kvm_pgtable_visit(struct kvm_pgtable_walk_data *data,
 		goto out;
 	}
 
-	childp = kvm_pte_follow(ctx.old, data->pgt->mm_ops);
-	ret = __kvm_pgtable_walk(data, childp, level + 1);
+	childp = kvm_pte_follow(ctx.old, mm_ops);
+	ret = __kvm_pgtable_walk(data, mm_ops, childp, level + 1);
 	if (ret)
 		goto out;
 
@@ -231,7 +233,7 @@ out:
 }
 
 static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data,
-			      kvm_pte_t *pgtable, u32 level)
+			      struct kvm_pgtable_mm_ops *mm_ops, kvm_pte_t *pgtable, u32 level)
 {
 	u32 idx;
 	int ret = 0;
@@ -245,7 +247,7 @@ static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data,
 		if (data->addr >= data->end)
 			break;
 
-		ret = __kvm_pgtable_visit(data, ptep, level);
+		ret = __kvm_pgtable_visit(data, mm_ops, ptep, level);
 		if (ret)
 			break;
 	}
@@ -269,7 +271,7 @@ static int _kvm_pgtable_walk(struct kvm_pgtable_walk_data *data)
 	for (idx = kvm_pgd_page_idx(data); data->addr < data->end; ++idx) {
 		kvm_pte_t *ptep = &pgt->pgd[idx * PTRS_PER_PTE];
 
-		ret = __kvm_pgtable_walk(data, ptep, pgt->start_level);
+		ret = __kvm_pgtable_walk(data, pgt->mm_ops, ptep, pgt->start_level);
 		if (ret)
 			break;
 	}
@@ -332,7 +334,6 @@ int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr,
 struct hyp_map_data {
 	u64				phys;
 	kvm_pte_t			attr;
-	struct kvm_pgtable_mm_ops	*mm_ops;
 };
 
 static int hyp_set_prot_attr(enum kvm_pgtable_prot prot, kvm_pte_t *ptep)
@@ -400,7 +401,7 @@ static bool hyp_map_walker_try_leaf(const struct kvm_pgtable_visit_ctx *ctx,
 	if (ctx->old == new)
 		return true;
 	if (!kvm_pte_valid(ctx->old))
-		data->mm_ops->get_page(ctx->ptep);
+		ctx->mm_ops->get_page(ctx->ptep);
 	else if (WARN_ON((ctx->old ^ new) & ~KVM_PTE_LEAF_ATTR_HI_SW))
 		return false;
 
@@ -413,7 +414,7 @@ static int hyp_map_walker(const struct kvm_pgtable_visit_ctx *ctx,
 {
 	kvm_pte_t *childp;
 	struct hyp_map_data *data = ctx->arg;
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (hyp_map_walker_try_leaf(ctx, data))
 		return 0;
@@ -436,7 +437,6 @@ int kvm_pgtable_hyp_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys,
 	int ret;
 	struct hyp_map_data map_data = {
 		.phys	= ALIGN_DOWN(phys, PAGE_SIZE),
-		.mm_ops	= pgt->mm_ops,
 	};
 	struct kvm_pgtable_walker walker = {
 		.cb	= hyp_map_walker,
@@ -454,18 +454,13 @@ int kvm_pgtable_hyp_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys,
 	return ret;
 }
 
-struct hyp_unmap_data {
-	u64				unmapped;
-	struct kvm_pgtable_mm_ops	*mm_ops;
-};
-
 static int hyp_unmap_walker(const struct kvm_pgtable_visit_ctx *ctx,
 			    enum kvm_pgtable_walk_flags visit)
 {
 	kvm_pte_t *childp = NULL;
 	u64 granule = kvm_granule_size(ctx->level);
-	struct hyp_unmap_data *data = ctx->arg;
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	u64 *unmapped = ctx->arg;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (!kvm_pte_valid(ctx->old))
 		return -EINVAL;
@@ -486,7 +481,7 @@ static int hyp_unmap_walker(const struct kvm_pgtable_visit_ctx *ctx,
 		kvm_clear_pte(ctx->ptep);
 		dsb(ishst);
 		__tlbi_level(vale2is, __TLBI_VADDR(ctx->addr, 0), ctx->level);
-		data->unmapped += granule;
+		*unmapped += granule;
 	}
 
 	dsb(ish);
@@ -501,12 +496,10 @@ static int hyp_unmap_walker(const struct kvm_pgtable_visit_ctx *ctx,
 
 u64 kvm_pgtable_hyp_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size)
 {
-	struct hyp_unmap_data unmap_data = {
-		.mm_ops	= pgt->mm_ops,
-	};
+	u64 unmapped = 0;
 	struct kvm_pgtable_walker walker = {
 		.cb	= hyp_unmap_walker,
-		.arg	= &unmap_data,
+		.arg	= &unmapped,
 		.flags	= KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
 	};
 
@@ -514,7 +507,7 @@ u64 kvm_pgtable_hyp_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size)
 		return 0;
 
 	kvm_pgtable_walk(pgt, addr, size, &walker);
-	return unmap_data.unmapped;
+	return unmapped;
 }
 
 int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits,
@@ -538,7 +531,7 @@ int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits,
 static int hyp_free_walker(const struct kvm_pgtable_visit_ctx *ctx,
 			   enum kvm_pgtable_walk_flags visit)
 {
-	struct kvm_pgtable_mm_ops *mm_ops = ctx->arg;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (!kvm_pte_valid(ctx->old))
 		return 0;
@@ -556,7 +549,6 @@ void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt)
 	struct kvm_pgtable_walker walker = {
 		.cb	= hyp_free_walker,
 		.flags	= KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
-		.arg	= pgt->mm_ops,
 	};
 
 	WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker));
@@ -575,8 +567,6 @@ struct stage2_map_data {
 	struct kvm_s2_mmu		*mmu;
 	void				*memcache;
 
-	struct kvm_pgtable_mm_ops	*mm_ops;
-
 	/* Force mappings to page granularity */
 	bool				force_pte;
 };
@@ -725,7 +715,7 @@ static int stage2_map_walker_try_leaf(const struct kvm_pgtable_visit_ctx *ctx,
 	kvm_pte_t new;
 	u64 granule = kvm_granule_size(ctx->level), phys = data->phys;
 	struct kvm_pgtable *pgt = data->mmu->pgt;
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (!stage2_leaf_mapping_allowed(ctx, data))
 		return -E2BIG;
@@ -773,7 +763,7 @@ static int stage2_map_walk_table_pre(const struct kvm_pgtable_visit_ctx *ctx,
 	if (!stage2_leaf_mapping_allowed(ctx, data))
 		return 0;
 
-	data->childp = kvm_pte_follow(ctx->old, data->mm_ops);
+	data->childp = kvm_pte_follow(ctx->old, ctx->mm_ops);
 	kvm_clear_pte(ctx->ptep);
 
 	/*
@@ -789,7 +779,7 @@ static int stage2_map_walk_table_pre(const struct kvm_pgtable_visit_ctx *ctx,
 static int stage2_map_walk_leaf(const struct kvm_pgtable_visit_ctx *ctx,
 				struct stage2_map_data *data)
 {
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 	kvm_pte_t *childp;
 	int ret;
 
@@ -831,7 +821,7 @@ static int stage2_map_walk_leaf(const struct kvm_pgtable_visit_ctx *ctx,
 static int stage2_map_walk_table_post(const struct kvm_pgtable_visit_ctx *ctx,
 				      struct stage2_map_data *data)
 {
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 	kvm_pte_t *childp;
 	int ret = 0;
 
@@ -898,7 +888,6 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size,
 		.phys		= ALIGN_DOWN(phys, PAGE_SIZE),
 		.mmu		= pgt->mmu,
 		.memcache	= mc,
-		.mm_ops		= pgt->mm_ops,
 		.force_pte	= pgt->force_pte_cb && pgt->force_pte_cb(addr, addr + size, prot),
 	};
 	struct kvm_pgtable_walker walker = {
@@ -929,7 +918,6 @@ int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size,
 		.phys		= KVM_PHYS_INVALID,
 		.mmu		= pgt->mmu,
 		.memcache	= mc,
-		.mm_ops		= pgt->mm_ops,
 		.owner_id	= owner_id,
 		.force_pte	= true,
 	};
@@ -953,7 +941,7 @@ static int stage2_unmap_walker(const struct kvm_pgtable_visit_ctx *ctx,
 {
 	struct kvm_pgtable *pgt = ctx->arg;
 	struct kvm_s2_mmu *mmu = pgt->mmu;
-	struct kvm_pgtable_mm_ops *mm_ops = pgt->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 	kvm_pte_t *childp = NULL;
 	bool need_flush = false;
 
@@ -1007,7 +995,6 @@ struct stage2_attr_data {
 	kvm_pte_t			attr_clr;
 	kvm_pte_t			pte;
 	u32				level;
-	struct kvm_pgtable_mm_ops	*mm_ops;
 };
 
 static int stage2_attr_walker(const struct kvm_pgtable_visit_ctx *ctx,
@@ -1015,7 +1002,7 @@ static int stage2_attr_walker(const struct kvm_pgtable_visit_ctx *ctx,
 {
 	kvm_pte_t pte = ctx->old;
 	struct stage2_attr_data *data = ctx->arg;
-	struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (!kvm_pte_valid(ctx->old))
 		return 0;
@@ -1055,7 +1042,6 @@ static int stage2_update_leaf_attrs(struct kvm_pgtable *pgt, u64 addr,
 	struct stage2_attr_data data = {
 		.attr_set	= attr_set & attr_mask,
 		.attr_clr	= attr_clr & attr_mask,
-		.mm_ops		= pgt->mm_ops,
 	};
 	struct kvm_pgtable_walker walker = {
 		.cb		= stage2_attr_walker,
@@ -1198,7 +1184,7 @@ int __kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm_s2_mmu *mmu,
 static int stage2_free_walker(const struct kvm_pgtable_visit_ctx *ctx,
 			      enum kvm_pgtable_walk_flags visit)
 {
-	struct kvm_pgtable_mm_ops *mm_ops = ctx->arg;
+	struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
 
 	if (!stage2_pte_is_counted(ctx->old))
 		return 0;
@@ -1218,7 +1204,6 @@ void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt)
 		.cb	= stage2_free_walker,
 		.flags	= KVM_PGTABLE_WALK_LEAF |
 			  KVM_PGTABLE_WALK_TABLE_POST,
-		.arg	= pgt->mm_ops,
 	};
 
 	WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker));