1 files changed, 66 insertions, 37 deletions

diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index aa12cd4078b3..02219e28b1e4 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -499,13 +499,14 @@ void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, unsigned int lpid)
 	unsigned long ig;
 
 	for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) {
+		p4d_t *p4d = p4d_offset(pgd, 0);
 		pud_t *pud;
 
-		if (!pgd_present(*pgd))
+		if (!p4d_present(*p4d))
 			continue;
-		pud = pud_offset(pgd, 0);
+		pud = pud_offset(p4d, 0);
 		kvmppc_unmap_free_pud(kvm, pud, lpid);
-		pgd_clear(pgd);
+		p4d_clear(p4d);
 	}
 }
 
@@ -566,6 +567,7 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
 		      unsigned long *rmapp, struct rmap_nested **n_rmap)
 {
 	pgd_t *pgd;
+	p4d_t *p4d;
 	pud_t *pud, *new_pud = NULL;
 	pmd_t *pmd, *new_pmd = NULL;
 	pte_t *ptep, *new_ptep = NULL;
@@ -573,9 +575,11 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
 
 	/* Traverse the guest's 2nd-level tree, allocate new levels needed */
 	pgd = pgtable + pgd_index(gpa);
+	p4d = p4d_offset(pgd, gpa);
+
 	pud = NULL;
-	if (pgd_present(*pgd))
-		pud = pud_offset(pgd, gpa);
+	if (p4d_present(*p4d))
+		pud = pud_offset(p4d, gpa);
 	else
 		new_pud = pud_alloc_one(kvm->mm, gpa);
 
@@ -596,13 +600,13 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
 
 	/* Now traverse again under the lock and change the tree */
 	ret = -ENOMEM;
-	if (pgd_none(*pgd)) {
+	if (p4d_none(*p4d)) {
 		if (!new_pud)
 			goto out_unlock;
-		pgd_populate(kvm->mm, pgd, new_pud);
+		p4d_populate(kvm->mm, p4d, new_pud);
 		new_pud = NULL;
 	}
-	pud = pud_offset(pgd, gpa);
+	pud = pud_offset(p4d, gpa);
 	if (pud_is_leaf(*pud)) {
 		unsigned long hgpa = gpa & PUD_MASK;
 
@@ -735,7 +739,7 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
 	return ret;
 }
 
-bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable, bool writing,
+bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested, bool writing,
 			     unsigned long gpa, unsigned int lpid)
 {
 	unsigned long pgflags;
@@ -750,12 +754,12 @@ bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable, bool writing,
 	pgflags = _PAGE_ACCESSED;
 	if (writing)
 		pgflags |= _PAGE_DIRTY;
-	/*
-	 * We are walking the secondary (partition-scoped) page table here.
-	 * We can do this without disabling irq because the Linux MM
-	 * subsystem doesn't do THP splits and collapses on this tree.
-	 */
-	ptep = __find_linux_pte(pgtable, gpa, NULL, &shift);
+
+	if (nested)
+		ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
+	else
+		ptep = find_kvm_secondary_pte(kvm, gpa, &shift);
+
 	if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) {
 		kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift);
 		return true;
@@ -813,12 +817,12 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
 	 * Read the PTE from the process' radix tree and use that
 	 * so we get the shift and attribute bits.
 	 */
-	local_irq_disable();
-	ptep = __find_linux_pte(vcpu->arch.pgdir, hva, NULL, &shift);
+	spin_lock(&kvm->mmu_lock);
+	ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift);
 	pte = __pte(0);
 	if (ptep)
-		pte = *ptep;
-	local_irq_enable();
+		pte = READ_ONCE(*ptep);
+	spin_unlock(&kvm->mmu_lock);
 	/*
 	 * If the PTE disappeared temporarily due to a THP
 	 * collapse, just return and let the guest try again.
@@ -949,8 +953,8 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	/* Failed to set the reference/change bits */
 	if (dsisr & DSISR_SET_RC) {
 		spin_lock(&kvm->mmu_lock);
-		if (kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable,
-					    writing, gpa, kvm->arch.lpid))
+		if (kvmppc_hv_handle_set_rc(kvm, false, writing,
+					    gpa, kvm->arch.lpid))
 			dsisr &= ~DSISR_SET_RC;
 		spin_unlock(&kvm->mmu_lock);
 
@@ -981,11 +985,11 @@ int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 		return 0;
 	}
 
-	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
+	ptep = find_kvm_secondary_pte(kvm, gpa, &shift);
 	if (ptep && pte_present(*ptep))
 		kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot,
 				 kvm->arch.lpid);
-	return 0;				
+	return 0;
 }
 
 /* Called with kvm->mmu_lock held */
@@ -1001,7 +1005,7 @@ int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 	if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE)
 		return ref;
 
-	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
+	ptep = find_kvm_secondary_pte(kvm, gpa, &shift);
 	if (ptep && pte_present(*ptep) && pte_young(*ptep)) {
 		old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0,
 					      gpa, shift);
@@ -1028,7 +1032,7 @@ int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 	if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE)
 		return ref;
 
-	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
+	ptep = find_kvm_secondary_pte(kvm, gpa, &shift);
 	if (ptep && pte_present(*ptep) && pte_young(*ptep))
 		ref = 1;
 	return ref;
@@ -1040,7 +1044,7 @@ static int kvm_radix_test_clear_dirty(struct kvm *kvm,
 {
 	unsigned long gfn = memslot->base_gfn + pagenum;
 	unsigned long gpa = gfn << PAGE_SHIFT;
-	pte_t *ptep;
+	pte_t *ptep, pte;
 	unsigned int shift;
 	int ret = 0;
 	unsigned long old, *rmapp;
@@ -1048,12 +1052,35 @@ static int kvm_radix_test_clear_dirty(struct kvm *kvm,
 	if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE)
 		return ret;
 
-	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
-	if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) {
-		ret = 1;
-		if (shift)
-			ret = 1 << (shift - PAGE_SHIFT);
+	/*
+	 * For performance reasons we don't hold kvm->mmu_lock while walking the
+	 * partition scoped table.
+	 */
+	ptep = find_kvm_secondary_pte_unlocked(kvm, gpa, &shift);
+	if (!ptep)
+		return 0;
+
+	pte = READ_ONCE(*ptep);
+	if (pte_present(pte) && pte_dirty(pte)) {
 		spin_lock(&kvm->mmu_lock);
+		/*
+		 * Recheck the pte again
+		 */
+		if (pte_val(pte) != pte_val(*ptep)) {
+			/*
+			 * We have KVM_MEM_LOG_DIRTY_PAGES enabled. Hence we can
+			 * only find PAGE_SIZE pte entries here. We can continue
+			 * to use the pte addr returned by above page table
+			 * walk.
+			 */
+			if (!pte_present(*ptep) || !pte_dirty(*ptep)) {
+				spin_unlock(&kvm->mmu_lock);
+				return 0;
+			}
+		}
+
+		ret = 1;
+		VM_BUG_ON(shift);
 		old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0,
 					      gpa, shift);
 		kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid);
@@ -1109,7 +1136,7 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm,
 	gpa = memslot->base_gfn << PAGE_SHIFT;
 	spin_lock(&kvm->mmu_lock);
 	for (n = memslot->npages; n; --n) {
-		ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
+		ptep = find_kvm_secondary_pte(kvm, gpa, &shift);
 		if (ptep && pte_present(*ptep))
 			kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot,
 					 kvm->arch.lpid);
@@ -1220,7 +1247,8 @@ static ssize_t debugfs_radix_read(struct file *file, char __user *buf,
 	unsigned long gpa;
 	pgd_t *pgt;
 	struct kvm_nested_guest *nested;
-	pgd_t pgd, *pgdp;
+	pgd_t *pgdp;
+	p4d_t p4d, *p4dp;
 	pud_t pud, *pudp;
 	pmd_t pmd, *pmdp;
 	pte_t *ptep;
@@ -1293,13 +1321,14 @@ static ssize_t debugfs_radix_read(struct file *file, char __user *buf,
 		}
 
 		pgdp = pgt + pgd_index(gpa);
-		pgd = READ_ONCE(*pgdp);
-		if (!(pgd_val(pgd) & _PAGE_PRESENT)) {
-			gpa = (gpa & PGDIR_MASK) + PGDIR_SIZE;
+		p4dp = p4d_offset(pgdp, gpa);
+		p4d = READ_ONCE(*p4dp);
+		if (!(p4d_val(p4d) & _PAGE_PRESENT)) {
+			gpa = (gpa & P4D_MASK) + P4D_SIZE;
 			continue;
 		}
 
-		pudp = pud_offset(&pgd, gpa);
+		pudp = pud_offset(&p4d, gpa);
 		pud = READ_ONCE(*pudp);
 		if (!(pud_val(pud) & _PAGE_PRESENT)) {
 			gpa = (gpa & PUD_MASK) + PUD_SIZE;