KVM/ARM Fixes for the Linux 3.11 release

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Merge tag 'kvm-arm-fixes-3.11' of git://git.linaro.org/people/cdall/linux-kvm-arm into kvm-master

KVM/ARM Fixes for the Linux 3.11 release

arch/arm/kvm/coproc.c

@@ -146,7 +146,11 @@ static bool pm_fake(struct kvm_vcpu *vcpu,
 #define access_pmintenclr pm_fake
 
 /* Architected CP15 registers.
- * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ * CRn denotes the primary register number, but is copied to the CRm in the
+ * user space API for 64-bit register access in line with the terminology used
+ * in the ARM ARM.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit
+ *            registers preceding 32-bit ones.
  */
 static const struct coproc_reg cp15_regs[] = {
 	/* CSSELR: swapped by interrupt.S. */
@@ -154,8 +158,8 @@ static const struct coproc_reg cp15_regs[] = {
 			NULL, reset_unknown, c0_CSSELR },
 
 	/* TTBR0/TTBR1: swapped by interrupt.S. */
-	{ CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
+	{ CRm64( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
-	{ CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
+	{ CRm64( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
 
 	/* TTBCR: swapped by interrupt.S. */
 	{ CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32,
@@ -182,7 +186,7 @@ static const struct coproc_reg cp15_regs[] = {
 			NULL, reset_unknown, c6_IFAR },
 
 	/* PAR swapped by interrupt.S */
-	{ CRn( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR },
+	{ CRm64( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR },
 
 	/*
 	 * DC{C,I,CI}SW operations:
@@ -399,12 +403,13 @@ static bool index_to_params(u64 id, struct coproc_params *params)
 			      | KVM_REG_ARM_OPC1_MASK))
 			return false;
 		params->is_64bit = true;
-		params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
+		/* CRm to CRn: see cp15_to_index for details */
+		params->CRn = ((id & KVM_REG_ARM_CRM_MASK)
 			       >> KVM_REG_ARM_CRM_SHIFT);
 		params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
 			       >> KVM_REG_ARM_OPC1_SHIFT);
 		params->Op2 = 0;
-		params->CRn = 0;
+		params->CRm = 0;
 		return true;
 	default:
 		return false;
@@ -898,7 +903,14 @@ static u64 cp15_to_index(const struct coproc_reg *reg)
 	if (reg->is_64) {
 		val |= KVM_REG_SIZE_U64;
 		val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
-		val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
+		/*
+		 * CRn always denotes the primary coproc. reg. nr. for the
+		 * in-kernel representation, but the user space API uses the
+		 * CRm for the encoding, because it is modelled after the
+		 * MRRC/MCRR instructions: see the ARM ARM rev. c page
+		 * B3-1445
+		 */
+		val |= (reg->CRn << KVM_REG_ARM_CRM_SHIFT);
 	} else {
 		val |= KVM_REG_SIZE_U32;
 		val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);

arch/arm/kvm/coproc.h

@@ -135,6 +135,8 @@ static inline int cmp_reg(const struct coproc_reg *i1,
 		return -1;
 	if (i1->CRn != i2->CRn)
 		return i1->CRn - i2->CRn;
+	if (i1->is_64 != i2->is_64)
+		return i2->is_64 - i1->is_64;
 	if (i1->CRm != i2->CRm)
 		return i1->CRm - i2->CRm;
 	if (i1->Op1 != i2->Op1)
@@ -145,6 +147,7 @@ static inline int cmp_reg(const struct coproc_reg *i1,
 
 #define CRn(_x)		.CRn = _x
 #define CRm(_x) 	.CRm = _x
+#define CRm64(_x)       .CRn = _x, .CRm = 0
 #define Op1(_x) 	.Op1 = _x
 #define Op2(_x) 	.Op2 = _x
 #define is64		.is_64 = true

arch/arm/kvm/coproc_a15.c

@@ -114,7 +114,11 @@ static bool access_l2ectlr(struct kvm_vcpu *vcpu,
 
 /*
  * A15-specific CP15 registers.
- * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ * CRn denotes the primary register number, but is copied to the CRm in the
+ * user space API for 64-bit register access in line with the terminology used
+ * in the ARM ARM.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit
+ *            registers preceding 32-bit ones.
  */
 static const struct coproc_reg a15_regs[] = {
 	/* MPIDR: we use VMPIDR for guest access. */

arch/arm/kvm/mmio.c

@@ -63,7 +63,8 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
 static int decode_hsr(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 		      struct kvm_exit_mmio *mmio)
 {
-	unsigned long rt, len;
+	unsigned long rt;
+	int len;
 	bool is_write, sign_extend;
 
 	if (kvm_vcpu_dabt_isextabt(vcpu)) {

arch/arm/kvm/mmu.c

@@ -85,6 +85,12 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
 	return p;
 }
 
+static bool page_empty(void *ptr)
+{
+	struct page *ptr_page = virt_to_page(ptr);
+	return page_count(ptr_page) == 1;
+}
+
 static void clear_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr)
 {
 	pmd_t *pmd_table = pmd_offset(pud, 0);
@@ -103,12 +109,6 @@ static void clear_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr)
 	put_page(virt_to_page(pmd));
 }
 
-static bool pmd_empty(pmd_t *pmd)
-{
-	struct page *pmd_page = virt_to_page(pmd);
-	return page_count(pmd_page) == 1;
-}
-
 static void clear_pte_entry(struct kvm *kvm, pte_t *pte, phys_addr_t addr)
 {
 	if (pte_present(*pte)) {
@@ -118,12 +118,6 @@ static void clear_pte_entry(struct kvm *kvm, pte_t *pte, phys_addr_t addr)
 	}
 }
 
-static bool pte_empty(pte_t *pte)
-{
-	struct page *pte_page = virt_to_page(pte);
-	return page_count(pte_page) == 1;
-}
-
 static void unmap_range(struct kvm *kvm, pgd_t *pgdp,
 			unsigned long long start, u64 size)
 {
@@ -132,37 +126,37 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp,
 	pmd_t *pmd;
 	pte_t *pte;
 	unsigned long long addr = start, end = start + size;
-	u64 range;
+	u64 next;
 
 	while (addr < end) {
 		pgd = pgdp + pgd_index(addr);
 		pud = pud_offset(pgd, addr);
 		if (pud_none(*pud)) {
-			addr += PUD_SIZE;
+			addr = pud_addr_end(addr, end);
 			continue;
 		}
 
 		pmd = pmd_offset(pud, addr);
 		if (pmd_none(*pmd)) {
-			addr += PMD_SIZE;
+			addr = pmd_addr_end(addr, end);
 			continue;
 		}
 
 		pte = pte_offset_kernel(pmd, addr);
 		clear_pte_entry(kvm, pte, addr);
-		range = PAGE_SIZE;
+		next = addr + PAGE_SIZE;
 
 		/* If we emptied the pte, walk back up the ladder */
-		if (pte_empty(pte)) {
+		if (page_empty(pte)) {
 			clear_pmd_entry(kvm, pmd, addr);
-			range = PMD_SIZE;
+			next = pmd_addr_end(addr, end);
-			if (pmd_empty(pmd)) {
+			if (page_empty(pmd) && !page_empty(pud)) {
 				clear_pud_entry(kvm, pud, addr);
-				range = PUD_SIZE;
+				next = pud_addr_end(addr, end);
 			}
 		}
 
-		addr += range;
+		addr = next;
 	}
 }