[PATCH 18/39] KVM: Replace read accesses of vcpu->arch.cr0 by an accessor

From: Avi Kivity
Date: Sat Feb 13 2010 - 03:07:07 EST


Since we'd like to allow the guest to own a few bits of cr0 at times, we need
to know when we access those bits.

Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
---
arch/x86/kvm/emulate.c | 6 +++---
arch/x86/kvm/kvm_cache_regs.h | 10 ++++++++++
arch/x86/kvm/mmu.c | 2 +-
arch/x86/kvm/mmu.h | 2 +-
arch/x86/kvm/svm.c | 9 +++++----
arch/x86/kvm/vmx.c | 16 ++++++++--------
arch/x86/kvm/x86.c | 20 ++++++++++----------
7 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 7e8faea..0f89e32 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1515,7 +1515,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)

/* syscall is not available in real mode */
if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
- || !(ctxt->vcpu->arch.cr0 & X86_CR0_PE))
+ || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE))
return -1;

setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1569,7 +1569,7 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)

/* inject #GP if in real mode or paging is disabled */
if (ctxt->mode == X86EMUL_MODE_REAL ||
- !(ctxt->vcpu->arch.cr0 & X86_CR0_PE)) {
+ !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
kvm_inject_gp(ctxt->vcpu, 0);
return -1;
}
@@ -1635,7 +1635,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)

/* inject #GP if in real mode or paging is disabled */
if (ctxt->mode == X86EMUL_MODE_REAL
- || !(ctxt->vcpu->arch.cr0 & X86_CR0_PE)) {
+ || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
kvm_inject_gp(ctxt->vcpu, 0);
return -1;
}
diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 35acc36..f468597 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -38,6 +38,16 @@ static inline u64 kvm_pdptr_read(struct kvm_vcpu *vcpu, int index)
return vcpu->arch.pdptrs[index];
}

+static inline ulong kvm_read_cr0_bits(struct kvm_vcpu *vcpu, ulong mask)
+{
+ return vcpu->arch.cr0 & mask;
+}
+
+static inline ulong kvm_read_cr0(struct kvm_vcpu *vcpu)
+{
+ return kvm_read_cr0_bits(vcpu, ~0UL);
+}
+
static inline ulong kvm_read_cr4_bits(struct kvm_vcpu *vcpu, ulong mask)
{
if (mask & vcpu->arch.cr4_guest_owned_bits)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4f5508c..276bf74 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -226,7 +226,7 @@ EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);

static int is_write_protection(struct kvm_vcpu *vcpu)
{
- return vcpu->arch.cr0 & X86_CR0_WP;
+ return kvm_read_cr0_bits(vcpu, X86_CR0_WP);
}

static int is_cpuid_PSE36(void)
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index ff58342..599159f 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -79,7 +79,7 @@ static inline int is_pse(struct kvm_vcpu *vcpu)

static inline int is_paging(struct kvm_vcpu *vcpu)
{
- return vcpu->arch.cr0 & X86_CR0_PG;
+ return kvm_read_cr0_bits(vcpu, X86_CR0_PG);
}

static inline int is_present_gpte(unsigned long pte)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index cf64fc0..d3246ce 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -980,7 +980,7 @@ static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
if (npt_enabled)
goto set;

- if ((vcpu->arch.cr0 & X86_CR0_TS) && !(cr0 & X86_CR0_TS)) {
+ if (kvm_read_cr0_bits(vcpu, X86_CR0_TS) && !(cr0 & X86_CR0_TS)) {
svm->vmcb->control.intercept_exceptions &= ~(1 << NM_VECTOR);
vcpu->fpu_active = 1;
}
@@ -1244,7 +1244,7 @@ static int ud_interception(struct vcpu_svm *svm)
static int nm_interception(struct vcpu_svm *svm)
{
svm->vmcb->control.intercept_exceptions &= ~(1 << NM_VECTOR);
- if (!(svm->vcpu.arch.cr0 & X86_CR0_TS))
+ if (!kvm_read_cr0_bits(&svm->vcpu, X86_CR0_TS))
svm->vmcb->save.cr0 &= ~X86_CR0_TS;
svm->vcpu.fpu_active = 1;

@@ -1743,7 +1743,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
hsave->save.gdtr = vmcb->save.gdtr;
hsave->save.idtr = vmcb->save.idtr;
hsave->save.efer = svm->vcpu.arch.shadow_efer;
- hsave->save.cr0 = svm->vcpu.arch.cr0;
+ hsave->save.cr0 = kvm_read_cr0(&svm->vcpu);
hsave->save.cr4 = svm->vcpu.arch.cr4;
hsave->save.rflags = vmcb->save.rflags;
hsave->save.rip = svm->next_rip;
@@ -2387,7 +2387,8 @@ static int handle_exit(struct kvm_vcpu *vcpu)

if (npt_enabled) {
int mmu_reload = 0;
- if ((vcpu->arch.cr0 ^ svm->vmcb->save.cr0) & X86_CR0_PG) {
+ if ((kvm_read_cr0_bits(vcpu, X86_CR0_PG) ^ svm->vmcb->save.cr0)
+ & X86_CR0_PG) {
svm_set_cr0(vcpu, svm->vmcb->save.cr0);
mmu_reload = 1;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7c7b2ee..4c7177c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -799,7 +799,7 @@ static void vmx_fpu_activate(struct kvm_vcpu *vcpu)
return;
vcpu->fpu_active = 1;
vmcs_clear_bits(GUEST_CR0, X86_CR0_TS);
- if (vcpu->arch.cr0 & X86_CR0_TS)
+ if (kvm_read_cr0_bits(vcpu, X86_CR0_TS))
vmcs_set_bits(GUEST_CR0, X86_CR0_TS);
update_exception_bitmap(vcpu);
}
@@ -1785,7 +1785,7 @@ static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)

vmx_flush_tlb(vcpu);
vmcs_writel(GUEST_CR3, guest_cr3);
- if (vcpu->arch.cr0 & X86_CR0_PE)
+ if (kvm_read_cr0_bits(vcpu, X86_CR0_PE))
vmx_fpu_deactivate(vcpu);
}

@@ -1840,7 +1840,7 @@ static void vmx_get_segment(struct kvm_vcpu *vcpu,

static int vmx_get_cpl(struct kvm_vcpu *vcpu)
{
- if (!(vcpu->arch.cr0 & X86_CR0_PE)) /* if real mode */
+ if (!kvm_read_cr0_bits(vcpu, X86_CR0_PE)) /* if real mode */
return 0;

if (vmx_get_rflags(vcpu) & X86_EFLAGS_VM) /* if virtual 8086 */
@@ -2095,7 +2095,7 @@ static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu)
static bool guest_state_valid(struct kvm_vcpu *vcpu)
{
/* real mode guest state checks */
- if (!(vcpu->arch.cr0 & X86_CR0_PE)) {
+ if (!kvm_read_cr0_bits(vcpu, X86_CR0_PE)) {
if (!rmode_segment_valid(vcpu, VCPU_SREG_CS))
return false;
if (!rmode_segment_valid(vcpu, VCPU_SREG_SS))
@@ -2580,7 +2580,7 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid);

vmx->vcpu.arch.cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET;
- vmx_set_cr0(&vmx->vcpu, vmx->vcpu.arch.cr0); /* enter rmode */
+ vmx_set_cr0(&vmx->vcpu, kvm_read_cr0(vcpu)); /* enter rmode */
vmx_set_cr4(&vmx->vcpu, 0);
vmx_set_efer(&vmx->vcpu, 0);
vmx_fpu_activate(&vmx->vcpu);
@@ -2996,8 +2996,8 @@ static int handle_cr(struct kvm_vcpu *vcpu)
case 2: /* clts */
vmx_fpu_deactivate(vcpu);
vcpu->arch.cr0 &= ~X86_CR0_TS;
- vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0);
- trace_kvm_cr_write(0, vcpu->arch.cr0);
+ vmcs_writel(CR0_READ_SHADOW, kvm_read_cr0(vcpu));
+ trace_kvm_cr_write(0, kvm_read_cr0(vcpu));
vmx_fpu_activate(vcpu);
skip_emulated_instruction(vcpu);
return 1;
@@ -3018,7 +3018,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
break;
case 3: /* lmsw */
val = (exit_qualification >> LMSW_SOURCE_DATA_SHIFT) & 0x0f;
- trace_kvm_cr_write(0, (vcpu->arch.cr0 & ~0xful) | val);
+ trace_kvm_cr_write(0, (kvm_read_cr0(vcpu) & ~0xful) | val);
kvm_lmsw(vcpu, val);

skip_emulated_instruction(vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c990424..748b15d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -430,7 +430,7 @@ void kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
{
if (cr0 & CR0_RESERVED_BITS) {
printk(KERN_DEBUG "set_cr0: 0x%lx #GP, reserved bits 0x%lx\n",
- cr0, vcpu->arch.cr0);
+ cr0, kvm_read_cr0(vcpu));
kvm_inject_gp(vcpu, 0);
return;
}
@@ -488,7 +488,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cr0);

void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
{
- kvm_set_cr0(vcpu, (vcpu->arch.cr0 & ~0x0ful) | (msw & 0x0f));
+ kvm_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~0x0ful) | (msw & 0x0f));
}
EXPORT_SYMBOL_GPL(kvm_lmsw);

@@ -3095,7 +3095,7 @@ int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address)

int emulate_clts(struct kvm_vcpu *vcpu)
{
- kvm_x86_ops->set_cr0(vcpu, vcpu->arch.cr0 & ~X86_CR0_TS);
+ kvm_x86_ops->set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
return X86EMUL_CONTINUE;
}

@@ -3714,7 +3714,7 @@ unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)

switch (cr) {
case 0:
- value = vcpu->arch.cr0;
+ value = kvm_read_cr0(vcpu);
break;
case 2:
value = vcpu->arch.cr2;
@@ -3741,7 +3741,7 @@ void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
{
switch (cr) {
case 0:
- kvm_set_cr0(vcpu, mk_cr_64(vcpu->arch.cr0, val));
+ kvm_set_cr0(vcpu, mk_cr_64(kvm_read_cr0(vcpu), val));
*rflags = kvm_get_rflags(vcpu);
break;
case 2:
@@ -4335,7 +4335,7 @@ int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
sregs->gdt.limit = dt.limit;
sregs->gdt.base = dt.base;

- sregs->cr0 = vcpu->arch.cr0;
+ sregs->cr0 = kvm_read_cr0(vcpu);
sregs->cr2 = vcpu->arch.cr2;
sregs->cr3 = vcpu->arch.cr3;
sregs->cr4 = kvm_read_cr4(vcpu);
@@ -4521,7 +4521,7 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
{
struct kvm_segment kvm_seg;

- if (is_vm86_segment(vcpu, seg) || !(vcpu->arch.cr0 & X86_CR0_PE))
+ if (is_vm86_segment(vcpu, seg) || !(kvm_read_cr0_bits(vcpu, X86_CR0_PE)))
return kvm_load_realmode_segment(vcpu, selector, seg);
if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))
return 1;
@@ -4799,7 +4799,7 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
&nseg_desc);
}

- kvm_x86_ops->set_cr0(vcpu, vcpu->arch.cr0 | X86_CR0_TS);
+ kvm_x86_ops->set_cr0(vcpu, kvm_read_cr0(vcpu) | X86_CR0_TS);
seg_desct_to_kvm_desct(&nseg_desc, tss_selector, &tr_seg);
tr_seg.type = 11;
kvm_set_segment(vcpu, &tr_seg, VCPU_SREG_TR);
@@ -4834,7 +4834,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
kvm_x86_ops->set_efer(vcpu, sregs->efer);
kvm_set_apic_base(vcpu, sregs->apic_base);

- mmu_reset_needed |= vcpu->arch.cr0 != sregs->cr0;
+ mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0;
kvm_x86_ops->set_cr0(vcpu, sregs->cr0);
vcpu->arch.cr0 = sregs->cr0;

@@ -4873,7 +4873,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
/* Older userspace won't unhalt the vcpu on reset. */
if (kvm_vcpu_is_bsp(vcpu) && kvm_rip_read(vcpu) == 0xfff0 &&
sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 &&
- !(vcpu->arch.cr0 & X86_CR0_PE))
+ !(kvm_read_cr0_bits(vcpu, X86_CR0_PE)))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;

vcpu_put(vcpu);
--
1.6.5.3

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