KVM: PPC: Book3S HV: Don't store values derivable from HPT order

Currently the kvm_hpt_info structure stores the hashed page table's order,
and also the number of HPTEs it contains and a mask for its size.  The
last two can be easily derived from the order, so remove them and just
calculate them as necessary with a couple of helper inlines.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/include/asm/kvm_book3s_64.h

@@ -356,6 +356,18 @@ extern void kvmppc_mmu_debugfs_init(struct kvm *kvm);
 
 extern void kvmhv_rm_send_ipi(int cpu);
 
+static inline unsigned long kvmppc_hpt_npte(struct kvm_hpt_info *hpt)
+{
+	/* HPTEs are 2**4 bytes long */
+	return 1UL << (hpt->order - 4);
+}
+
+static inline unsigned long kvmppc_hpt_mask(struct kvm_hpt_info *hpt)
+{
+	/* 128 (2**7) bytes in each HPTEG */
+	return (1UL << (hpt->order - 7)) - 1;
+}
+
 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 
 #endif /* __ASM_KVM_BOOK3S_64_H__ */

arch/powerpc/include/asm/kvm_host.h

@@ -246,8 +246,6 @@ struct kvm_hpt_info {
 	unsigned long virt;
 	/* Array of reverse mapping entries for each guest HPTE */
 	struct revmap_entry *rev;
-	unsigned long npte;
-	unsigned long mask;
 	/* Guest HPT size is 2**(order) bytes */
 	u32 order;
 	/* 1 if HPT allocated with CMA, 0 otherwise */

arch/powerpc/kvm/book3s_64_mmu_hv.c

@@ -83,15 +83,11 @@ long kvmppc_alloc_hpt(struct kvm *kvm, u32 *htab_orderp)
 
 	kvm->arch.hpt.virt = hpt;
 	kvm->arch.hpt.order = order;
-	/* HPTEs are 2**4 bytes long */
-	kvm->arch.hpt.npte = 1ul << (order - 4);
-	/* 128 (2**7) bytes in each HPTEG */
-	kvm->arch.hpt.mask = (1ul << (order - 7)) - 1;
 
 	atomic64_set(&kvm->arch.mmio_update, 0);
 
 	/* Allocate reverse map array */
-	rev = vmalloc(sizeof(struct revmap_entry) * kvm->arch.hpt.npte);
+	rev = vmalloc(sizeof(struct revmap_entry) * kvmppc_hpt_npte(&kvm->arch.hpt));
 	if (!rev) {
 		pr_err("kvmppc_alloc_hpt: Couldn't alloc reverse map array\n");
 		goto out_freehpt;
@@ -196,8 +192,8 @@ void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
 	if (npages > 1ul << (40 - porder))
 		npages = 1ul << (40 - porder);
 	/* Can't use more than 1 HPTE per HPTEG */
-	if (npages > kvm->arch.hpt.mask + 1)
-		npages = kvm->arch.hpt.mask + 1;
+	if (npages > kvmppc_hpt_mask(&kvm->arch.hpt) + 1)
+		npages = kvmppc_hpt_mask(&kvm->arch.hpt) + 1;
 
 	hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
 		HPTE_V_BOLTED | hpte0_pgsize_encoding(psize);
@@ -207,7 +203,8 @@ void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
 	for (i = 0; i < npages; ++i) {
 		addr = i << porder;
 		/* can't use hpt_hash since va > 64 bits */
-		hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25))) & kvm->arch.hpt.mask;
+		hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25)))
+			& kvmppc_hpt_mask(&kvm->arch.hpt);
 		/*
 		 * We assume that the hash table is empty and no
 		 * vcpus are using it at this stage.  Since we create
@@ -1327,7 +1324,7 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf,
 
 		/* Skip uninteresting entries, i.e. clean on not-first pass */
 		if (!first_pass) {
-			while (i < kvm->arch.hpt.npte &&
+			while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
 			       !hpte_dirty(revp, hptp)) {
 				++i;
 				hptp += 2;
@@ -1337,7 +1334,7 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf,
 		hdr.index = i;
 
 		/* Grab a series of valid entries */
-		while (i < kvm->arch.hpt.npte &&
+		while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
 		       hdr.n_valid < 0xffff &&
 		       nb + HPTE_SIZE < count &&
 		       record_hpte(flags, hptp, hpte, revp, 1, first_pass)) {
@@ -1353,7 +1350,7 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf,
 			++revp;
 		}
 		/* Now skip invalid entries while we can */
-		while (i < kvm->arch.hpt.npte &&
+		while (i < kvmppc_hpt_npte(&kvm->arch.hpt) &&
 		       hdr.n_invalid < 0xffff &&
 		       record_hpte(flags, hptp, hpte, revp, 0, first_pass)) {
 			/* found an invalid entry */
@@ -1374,7 +1371,7 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf,
 		}
 
 		/* Check if we've wrapped around the hash table */
-		if (i >= kvm->arch.hpt.npte) {
+		if (i >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
 			i = 0;
 			ctx->first_pass = 0;
 			break;
@@ -1433,8 +1430,8 @@ static ssize_t kvm_htab_write(struct file *file, const char __user *buf,
 
 		err = -EINVAL;
 		i = hdr.index;
-		if (i >= kvm->arch.hpt.npte ||
-		    i + hdr.n_valid + hdr.n_invalid > kvm->arch.hpt.npte)
+		if (i >= kvmppc_hpt_npte(&kvm->arch.hpt) ||
+		    i + hdr.n_valid + hdr.n_invalid > kvmppc_hpt_npte(&kvm->arch.hpt))
 			break;
 
 		hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
@@ -1625,7 +1622,8 @@ static ssize_t debugfs_htab_read(struct file *file, char __user *buf,
 	kvm = p->kvm;
 	i = p->hpt_index;
 	hptp = (__be64 *)(kvm->arch.hpt.virt + (i * HPTE_SIZE));
-	for (; len != 0 && i < kvm->arch.hpt.npte; ++i, hptp += 2) {
+	for (; len != 0 && i < kvmppc_hpt_npte(&kvm->arch.hpt);
+	     ++i, hptp += 2) {
 		if (!(be64_to_cpu(hptp[0]) & (HPTE_V_VALID | HPTE_V_ABSENT)))
 			continue;
 

arch/powerpc/kvm/book3s_hv_rm_mmu.c

@@ -292,7 +292,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
 
 	/* Find and lock the HPTEG slot to use */
  do_insert:
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 	if (likely((flags & H_EXACT) == 0)) {
 		pte_index &= ~7UL;
@@ -469,7 +469,7 @@ long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
 
 	if (kvm_is_radix(kvm))
 		return H_FUNCTION;
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
 	while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
@@ -557,7 +557,7 @@ long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
 				break;
 			}
 			if (req != 1 || flags == 3 ||
-			    pte_index >= kvm->arch.hpt.npte) {
+			    pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
 				/* parameter error */
 				args[j] = ((0xa0 | flags) << 56) + pte_index;
 				ret = H_PARAMETER;
@@ -657,7 +657,7 @@ long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
 
 	if (kvm_is_radix(kvm))
 		return H_FUNCTION;
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 
 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
@@ -728,7 +728,7 @@ long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
 
 	if (kvm_is_radix(kvm))
 		return H_FUNCTION;
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 	if (flags & H_READ_4) {
 		pte_index &= ~3;
@@ -769,7 +769,7 @@ long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags,
 
 	if (kvm_is_radix(kvm))
 		return H_FUNCTION;
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 
 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
@@ -817,7 +817,7 @@ long kvmppc_h_clear_mod(struct kvm_vcpu *vcpu, unsigned long flags,
 
 	if (kvm_is_radix(kvm))
 		return H_FUNCTION;
-	if (pte_index >= kvm->arch.hpt.npte)
+	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
 		return H_PARAMETER;
 
 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
@@ -970,7 +970,7 @@ long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
 		somask = (1UL << 28) - 1;
 		vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT;
 	}
-	hash = (vsid ^ ((eaddr & somask) >> pshift)) & kvm->arch.hpt.mask;
+	hash = (vsid ^ ((eaddr & somask) >> pshift)) & kvmppc_hpt_mask(&kvm->arch.hpt);
 	avpn = slb_v & ~(somask >> 16);	/* also includes B */
 	avpn |= (eaddr & somask) >> 16;
 
@@ -1017,7 +1017,7 @@ long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
 		if (val & HPTE_V_SECONDARY)
 			break;
 		val |= HPTE_V_SECONDARY;
-		hash = hash ^ kvm->arch.hpt.mask;
+		hash = hash ^ kvmppc_hpt_mask(&kvm->arch.hpt);
 	}
 	return -1;
 }