KVM: x86: move MTRR related code to a separate file

MTRR code locates in x86.c and mmu.c so that move them to a separate file to
make the organization more clearer and it will be the place where we fully
implement vMTRR

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 335 insertions, 0 deletions

diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c
new file mode 100644
index 000000000000..fb2f7e10e8bc
--- /dev/null
+++ b/arch/x86/kvm/mtrr.c
@@ -0,0 +1,335 @@
+/*
+ * vMTRR implementation
+ *
+ * Copyright (C) 2006 Qumranet, Inc.
+ * Copyright 2010 Red Hat, Inc. and/or its affiliates.
+ * Copyright(C) 2015 Intel Corporation.
+ *
+ * Authors:
+ *   Yaniv Kamay  <yaniv@qumranet.com>
+ *   Avi Kivity   <avi@qumranet.com>
+ *   Marcelo Tosatti <mtosatti@redhat.com>
+ *   Paolo Bonzini <pbonzini@redhat.com>
+ *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/kvm_host.h>
+#include <asm/mtrr.h>
+
+#include "cpuid.h"
+#include "mmu.h"
+
+static bool msr_mtrr_valid(unsigned msr)
+{
+	switch (msr) {
+	case 0x200 ... 0x200 + 2 * KVM_NR_VAR_MTRR - 1:
+	case MSR_MTRRfix64K_00000:
+	case MSR_MTRRfix16K_80000:
+	case MSR_MTRRfix16K_A0000:
+	case MSR_MTRRfix4K_C0000:
+	case MSR_MTRRfix4K_C8000:
+	case MSR_MTRRfix4K_D0000:
+	case MSR_MTRRfix4K_D8000:
+	case MSR_MTRRfix4K_E0000:
+	case MSR_MTRRfix4K_E8000:
+	case MSR_MTRRfix4K_F0000:
+	case MSR_MTRRfix4K_F8000:
+	case MSR_MTRRdefType:
+	case MSR_IA32_CR_PAT:
+		return true;
+	case 0x2f8:
+		return true;
+	}
+	return false;
+}
+
+static bool valid_pat_type(unsigned t)
+{
+	return t < 8 && (1 << t) & 0xf3; /* 0, 1, 4, 5, 6, 7 */
+}
+
+static bool valid_mtrr_type(unsigned t)
+{
+	return t < 8 && (1 << t) & 0x73; /* 0, 1, 4, 5, 6 */
+}
+
+bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+{
+	int i;
+	u64 mask;
+
+	if (!msr_mtrr_valid(msr))
+		return false;
+
+	if (msr == MSR_IA32_CR_PAT) {
+		for (i = 0; i < 8; i++)
+			if (!valid_pat_type((data >> (i * 8)) & 0xff))
+				return false;
+		return true;
+	} else if (msr == MSR_MTRRdefType) {
+		if (data & ~0xcff)
+			return false;
+		return valid_mtrr_type(data & 0xff);
+	} else if (msr >= MSR_MTRRfix64K_00000 && msr <= MSR_MTRRfix4K_F8000) {
+		for (i = 0; i < 8 ; i++)
+			if (!valid_mtrr_type((data >> (i * 8)) & 0xff))
+				return false;
+		return true;
+	}
+
+	/* variable MTRRs */
+	WARN_ON(!(msr >= 0x200 && msr < 0x200 + 2 * KVM_NR_VAR_MTRR));
+
+	mask = (~0ULL) << cpuid_maxphyaddr(vcpu);
+	if ((msr & 1) == 0) {
+		/* MTRR base */
+		if (!valid_mtrr_type(data & 0xff))
+			return false;
+		mask |= 0xf00;
+	} else
+		/* MTRR mask */
+		mask |= 0x7ff;
+	if (data & mask) {
+		kvm_inject_gp(vcpu, 0);
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(kvm_mtrr_valid);
+
+static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr)
+{
+	struct mtrr_state_type *mtrr_state = &vcpu->arch.mtrr_state;
+	unsigned char mtrr_enabled = mtrr_state->enabled;
+	gfn_t start, end, mask;
+	int index;
+	bool is_fixed = true;
+
+	if (msr == MSR_IA32_CR_PAT || !tdp_enabled ||
+	      !kvm_arch_has_noncoherent_dma(vcpu->kvm))
+		return;
+
+	if (!(mtrr_enabled & 0x2) && msr != MSR_MTRRdefType)
+		return;
+
+	switch (msr) {
+	case MSR_MTRRfix64K_00000:
+		start = 0x0;
+		end = 0x80000;
+		break;
+	case MSR_MTRRfix16K_80000:
+		start = 0x80000;
+		end = 0xa0000;
+		break;
+	case MSR_MTRRfix16K_A0000:
+		start = 0xa0000;
+		end = 0xc0000;
+		break;
+	case MSR_MTRRfix4K_C0000 ... MSR_MTRRfix4K_F8000:
+		index = msr - MSR_MTRRfix4K_C0000;
+		start = 0xc0000 + index * (32 << 10);
+		end = start + (32 << 10);
+		break;
+	case MSR_MTRRdefType:
+		is_fixed = false;
+		start = 0x0;
+		end = ~0ULL;
+		break;
+	default:
+		/* variable range MTRRs. */
+		is_fixed = false;
+		index = (msr - 0x200) / 2;
+		start = (((u64)mtrr_state->var_ranges[index].base_hi) << 32) +
+		       (mtrr_state->var_ranges[index].base_lo & PAGE_MASK);
+		mask = (((u64)mtrr_state->var_ranges[index].mask_hi) << 32) +
+		       (mtrr_state->var_ranges[index].mask_lo & PAGE_MASK);
+		mask |= ~0ULL << cpuid_maxphyaddr(vcpu);
+
+		end = ((start & mask) | ~mask) + 1;
+	}
+
+	if (is_fixed && !(mtrr_enabled & 0x1))
+		return;
+
+	kvm_zap_gfn_range(vcpu->kvm, gpa_to_gfn(start), gpa_to_gfn(end));
+}
+
+int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+{
+	u64 *p = (u64 *)&vcpu->arch.mtrr_state.fixed_ranges;
+
+	if (!kvm_mtrr_valid(vcpu, msr, data))
+		return 1;
+
+	if (msr == MSR_MTRRdefType) {
+		vcpu->arch.mtrr_state.def_type = data;
+		vcpu->arch.mtrr_state.enabled = (data & 0xc00) >> 10;
+	} else if (msr == MSR_MTRRfix64K_00000)
+		p[0] = data;
+	else if (msr == MSR_MTRRfix16K_80000 || msr == MSR_MTRRfix16K_A0000)
+		p[1 + msr - MSR_MTRRfix16K_80000] = data;
+	else if (msr >= MSR_MTRRfix4K_C0000 && msr <= MSR_MTRRfix4K_F8000)
+		p[3 + msr - MSR_MTRRfix4K_C0000] = data;
+	else if (msr == MSR_IA32_CR_PAT)
+		vcpu->arch.pat = data;
+	else {	/* Variable MTRRs */
+		int idx, is_mtrr_mask;
+		u64 *pt;
+
+		idx = (msr - 0x200) / 2;
+		is_mtrr_mask = msr - 0x200 - 2 * idx;
+		if (!is_mtrr_mask)
+			pt =
+			  (u64 *)&vcpu->arch.mtrr_state.var_ranges[idx].base_lo;
+		else
+			pt =
+			  (u64 *)&vcpu->arch.mtrr_state.var_ranges[idx].mask_lo;
+		*pt = data;
+	}
+
+	update_mtrr(vcpu, msr);
+	return 0;
+}
+
+int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
+{
+	u64 *p = (u64 *)&vcpu->arch.mtrr_state.fixed_ranges;
+
+	if (!msr_mtrr_valid(msr))
+		return 1;
+
+	if (msr == MSR_MTRRdefType)
+		*pdata = vcpu->arch.mtrr_state.def_type +
+			 (vcpu->arch.mtrr_state.enabled << 10);
+	else if (msr == MSR_MTRRfix64K_00000)
+		*pdata = p[0];
+	else if (msr == MSR_MTRRfix16K_80000 || msr == MSR_MTRRfix16K_A0000)
+		*pdata = p[1 + msr - MSR_MTRRfix16K_80000];
+	else if (msr >= MSR_MTRRfix4K_C0000 && msr <= MSR_MTRRfix4K_F8000)
+		*pdata = p[3 + msr - MSR_MTRRfix4K_C0000];
+	else if (msr == MSR_IA32_CR_PAT)
+		*pdata = vcpu->arch.pat;
+	else {	/* Variable MTRRs */
+		int idx, is_mtrr_mask;
+		u64 *pt;
+
+		idx = (msr - 0x200) / 2;
+		is_mtrr_mask = msr - 0x200 - 2 * idx;
+		if (!is_mtrr_mask)
+			pt =
+			  (u64 *)&vcpu->arch.mtrr_state.var_ranges[idx].base_lo;
+		else
+			pt =
+			  (u64 *)&vcpu->arch.mtrr_state.var_ranges[idx].mask_lo;
+		*pdata = *pt;
+	}
+
+	return 0;
+}
+
+/*
+ * The function is based on mtrr_type_lookup() in
+ * arch/x86/kernel/cpu/mtrr/generic.c
+ */
+static int get_mtrr_type(struct mtrr_state_type *mtrr_state,
+			 u64 start, u64 end)
+{
+	u64 base, mask;
+	u8 prev_match, curr_match;
+	int i, num_var_ranges = KVM_NR_VAR_MTRR;
+
+	/* MTRR is completely disabled, use UC for all of physical memory. */
+	if (!(mtrr_state->enabled & 0x2))
+		return MTRR_TYPE_UNCACHABLE;
+
+	/* Make end inclusive end, instead of exclusive */
+	end--;
+
+	/* Look in fixed ranges. Just return the type as per start */
+	if (mtrr_state->have_fixed && (mtrr_state->enabled & 0x1) &&
+	      (start < 0x100000)) {
+		int idx;
+
+		if (start < 0x80000) {
+			idx = 0;
+			idx += (start >> 16);
+			return mtrr_state->fixed_ranges[idx];
+		} else if (start < 0xC0000) {
+			idx = 1 * 8;
+			idx += ((start - 0x80000) >> 14);
+			return mtrr_state->fixed_ranges[idx];
+		} else if (start < 0x1000000) {
+			idx = 3 * 8;
+			idx += ((start - 0xC0000) >> 12);
+			return mtrr_state->fixed_ranges[idx];
+		}
+	}
+
+	/*
+	 * Look in variable ranges
+	 * Look of multiple ranges matching this address and pick type
+	 * as per MTRR precedence
+	 */
+	prev_match = 0xFF;
+	for (i = 0; i < num_var_ranges; ++i) {
+		unsigned short start_state, end_state;
+
+		if (!(mtrr_state->var_ranges[i].mask_lo & (1 << 11)))
+			continue;
+
+		base = (((u64)mtrr_state->var_ranges[i].base_hi) << 32) +
+		       (mtrr_state->var_ranges[i].base_lo & PAGE_MASK);
+		mask = (((u64)mtrr_state->var_ranges[i].mask_hi) << 32) +
+		       (mtrr_state->var_ranges[i].mask_lo & PAGE_MASK);
+
+		start_state = ((start & mask) == (base & mask));
+		end_state = ((end & mask) == (base & mask));
+		if (start_state != end_state)
+			return 0xFE;
+
+		if ((start & mask) != (base & mask))
+			continue;
+
+		curr_match = mtrr_state->var_ranges[i].base_lo & 0xff;
+		if (prev_match == 0xFF) {
+			prev_match = curr_match;
+			continue;
+		}
+
+		if (prev_match == MTRR_TYPE_UNCACHABLE ||
+		    curr_match == MTRR_TYPE_UNCACHABLE)
+			return MTRR_TYPE_UNCACHABLE;
+
+		if ((prev_match == MTRR_TYPE_WRBACK &&
+		     curr_match == MTRR_TYPE_WRTHROUGH) ||
+		    (prev_match == MTRR_TYPE_WRTHROUGH &&
+		     curr_match == MTRR_TYPE_WRBACK)) {
+			prev_match = MTRR_TYPE_WRTHROUGH;
+			curr_match = MTRR_TYPE_WRTHROUGH;
+		}
+
+		if (prev_match != curr_match)
+			return MTRR_TYPE_UNCACHABLE;
+	}
+
+	if (prev_match != 0xFF)
+		return prev_match;
+
+	return mtrr_state->def_type;
+}
+
+u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn)
+{
+	u8 mtrr;
+
+	mtrr = get_mtrr_type(&vcpu->arch.mtrr_state, gfn << PAGE_SHIFT,
+			     (gfn << PAGE_SHIFT) + PAGE_SIZE);
+	if (mtrr == 0xfe || mtrr == 0xff)
+		mtrr = MTRR_TYPE_WRBACK;
+	return mtrr;
+}
+EXPORT_SYMBOL_GPL(kvm_mtrr_get_guest_memory_type);