[PATCH 2/6] KVM: SVM: Add manipulation functions for CRx intercepts

From: Joerg Roedel
Date: Tue Nov 30 2010 - 09:30:21 EST


This patch wraps changes to the CRx intercepts of SVM into
seperate functions to abstract nested-svm better and prepare
the implementation of the vmcb-clean-bits feature.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/include/asm/svm.h | 15 +++--
arch/x86/kvm/svm.c | 120 +++++++++++++++++++++++--------------------
2 files changed, 73 insertions(+), 62 deletions(-)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 0e83105..39f9ddf 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -51,8 +51,7 @@ enum {


struct __attribute__ ((__packed__)) vmcb_control_area {
- u16 intercept_cr_read;
- u16 intercept_cr_write;
+ u32 intercept_cr;
u16 intercept_dr_read;
u16 intercept_dr_write;
u32 intercept_exceptions;
@@ -204,10 +203,14 @@ struct __attribute__ ((__packed__)) vmcb {
#define SVM_SELECTOR_READ_MASK SVM_SELECTOR_WRITE_MASK
#define SVM_SELECTOR_CODE_MASK (1 << 3)

-#define INTERCEPT_CR0_MASK 1
-#define INTERCEPT_CR3_MASK (1 << 3)
-#define INTERCEPT_CR4_MASK (1 << 4)
-#define INTERCEPT_CR8_MASK (1 << 8)
+#define INTERCEPT_CR0_READ 0
+#define INTERCEPT_CR3_READ 3
+#define INTERCEPT_CR4_READ 4
+#define INTERCEPT_CR8_READ 8
+#define INTERCEPT_CR0_WRITE (16 + 0)
+#define INTERCEPT_CR3_WRITE (16 + 3)
+#define INTERCEPT_CR4_WRITE (16 + 4)
+#define INTERCEPT_CR8_WRITE (16 + 8)

#define INTERCEPT_DR0_MASK 1
#define INTERCEPT_DR1_MASK (1 << 1)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 05fe851..57c597b 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -98,8 +98,7 @@ struct nested_state {
unsigned long vmexit_rax;

/* cache for intercepts of the guest */
- u16 intercept_cr_read;
- u16 intercept_cr_write;
+ u32 intercept_cr;
u16 intercept_dr_read;
u16 intercept_dr_write;
u32 intercept_exceptions;
@@ -204,14 +203,46 @@ static void recalc_intercepts(struct vcpu_svm *svm)
h = &svm->nested.hsave->control;
g = &svm->nested;

- c->intercept_cr_read = h->intercept_cr_read | g->intercept_cr_read;
- c->intercept_cr_write = h->intercept_cr_write | g->intercept_cr_write;
+ c->intercept_cr = h->intercept_cr | g->intercept_cr;
c->intercept_dr_read = h->intercept_dr_read | g->intercept_dr_read;
c->intercept_dr_write = h->intercept_dr_write | g->intercept_dr_write;
c->intercept_exceptions = h->intercept_exceptions | g->intercept_exceptions;
c->intercept = h->intercept | g->intercept;
}

+static inline struct vmcb *get_host_vmcb(struct vcpu_svm *svm)
+{
+ if (is_guest_mode(&svm->vcpu))
+ return svm->nested.hsave;
+ else
+ return svm->vmcb;
+}
+
+static inline void set_cr_intercept(struct vcpu_svm *svm, int bit)
+{
+ struct vmcb *vmcb = get_host_vmcb(svm);
+
+ vmcb->control.intercept_cr |= (1U << bit);
+
+ recalc_intercepts(svm);
+}
+
+static inline void clr_cr_intercept(struct vcpu_svm *svm, int bit)
+{
+ struct vmcb *vmcb = get_host_vmcb(svm);
+
+ vmcb->control.intercept_cr &= ~(1U << bit);
+
+ recalc_intercepts(svm);
+}
+
+static inline bool is_cr_intercept(struct vcpu_svm *svm, int bit)
+{
+ struct vmcb *vmcb = get_host_vmcb(svm);
+
+ return vmcb->control.intercept_cr & (1U << bit);
+}
+
static inline void enable_gif(struct vcpu_svm *svm)
{
svm->vcpu.arch.hflags |= HF_GIF_MASK;
@@ -766,15 +797,15 @@ static void init_vmcb(struct vcpu_svm *svm)
struct vmcb_save_area *save = &svm->vmcb->save;

svm->vcpu.fpu_active = 1;
+ svm->vcpu.arch.hflags = 0;

- control->intercept_cr_read = INTERCEPT_CR0_MASK |
- INTERCEPT_CR3_MASK |
- INTERCEPT_CR4_MASK;
-
- control->intercept_cr_write = INTERCEPT_CR0_MASK |
- INTERCEPT_CR3_MASK |
- INTERCEPT_CR4_MASK |
- INTERCEPT_CR8_MASK;
+ set_cr_intercept(svm, INTERCEPT_CR0_READ);
+ set_cr_intercept(svm, INTERCEPT_CR3_READ);
+ set_cr_intercept(svm, INTERCEPT_CR4_READ);
+ set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
+ set_cr_intercept(svm, INTERCEPT_CR3_WRITE);
+ set_cr_intercept(svm, INTERCEPT_CR4_WRITE);
+ set_cr_intercept(svm, INTERCEPT_CR8_WRITE);

control->intercept_dr_read = INTERCEPT_DR0_MASK |
INTERCEPT_DR1_MASK |
@@ -875,8 +906,8 @@ static void init_vmcb(struct vcpu_svm *svm)
control->intercept &= ~((1ULL << INTERCEPT_TASK_SWITCH) |
(1ULL << INTERCEPT_INVLPG));
control->intercept_exceptions &= ~(1 << PF_VECTOR);
- control->intercept_cr_read &= ~INTERCEPT_CR3_MASK;
- control->intercept_cr_write &= ~INTERCEPT_CR3_MASK;
+ clr_cr_intercept(svm, INTERCEPT_CR3_READ);
+ clr_cr_intercept(svm, INTERCEPT_CR3_WRITE);
save->g_pat = 0x0007040600070406ULL;
save->cr3 = 0;
save->cr4 = 0;
@@ -1210,7 +1241,6 @@ static void svm_decache_cr4_guest_bits(struct kvm_vcpu *vcpu)

static void update_cr0_intercept(struct vcpu_svm *svm)
{
- struct vmcb *vmcb = svm->vmcb;
ulong gcr0 = svm->vcpu.arch.cr0;
u64 *hcr0 = &svm->vmcb->save.cr0;

@@ -1222,25 +1252,11 @@ static void update_cr0_intercept(struct vcpu_svm *svm)


if (gcr0 == *hcr0 && svm->vcpu.fpu_active) {
- vmcb->control.intercept_cr_read &= ~INTERCEPT_CR0_MASK;
- vmcb->control.intercept_cr_write &= ~INTERCEPT_CR0_MASK;
- if (is_guest_mode(&svm->vcpu)) {
- struct vmcb *hsave = svm->nested.hsave;
-
- hsave->control.intercept_cr_read &= ~INTERCEPT_CR0_MASK;
- hsave->control.intercept_cr_write &= ~INTERCEPT_CR0_MASK;
- vmcb->control.intercept_cr_read |= svm->nested.intercept_cr_read;
- vmcb->control.intercept_cr_write |= svm->nested.intercept_cr_write;
- }
+ clr_cr_intercept(svm, INTERCEPT_CR0_READ);
+ clr_cr_intercept(svm, INTERCEPT_CR0_WRITE);
} else {
- svm->vmcb->control.intercept_cr_read |= INTERCEPT_CR0_MASK;
- svm->vmcb->control.intercept_cr_write |= INTERCEPT_CR0_MASK;
- if (is_guest_mode(&svm->vcpu)) {
- struct vmcb *hsave = svm->nested.hsave;
-
- hsave->control.intercept_cr_read |= INTERCEPT_CR0_MASK;
- hsave->control.intercept_cr_write |= INTERCEPT_CR0_MASK;
- }
+ set_cr_intercept(svm, INTERCEPT_CR0_READ);
+ set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
}
}

@@ -1900,15 +1916,9 @@ static int nested_svm_intercept(struct vcpu_svm *svm)
case SVM_EXIT_IOIO:
vmexit = nested_svm_intercept_ioio(svm);
break;
- case SVM_EXIT_READ_CR0 ... SVM_EXIT_READ_CR8: {
- u32 cr_bits = 1 << (exit_code - SVM_EXIT_READ_CR0);
- if (svm->nested.intercept_cr_read & cr_bits)
- vmexit = NESTED_EXIT_DONE;
- break;
- }
- case SVM_EXIT_WRITE_CR0 ... SVM_EXIT_WRITE_CR8: {
- u32 cr_bits = 1 << (exit_code - SVM_EXIT_WRITE_CR0);
- if (svm->nested.intercept_cr_write & cr_bits)
+ case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
+ u32 bit = 1U << (exit_code - SVM_EXIT_READ_CR0);
+ if (svm->nested.intercept_cr & bit)
vmexit = NESTED_EXIT_DONE;
break;
}
@@ -1965,8 +1975,7 @@ static inline void copy_vmcb_control_area(struct vmcb *dst_vmcb, struct vmcb *fr
struct vmcb_control_area *dst = &dst_vmcb->control;
struct vmcb_control_area *from = &from_vmcb->control;

- dst->intercept_cr_read = from->intercept_cr_read;
- dst->intercept_cr_write = from->intercept_cr_write;
+ dst->intercept_cr = from->intercept_cr;
dst->intercept_dr_read = from->intercept_dr_read;
dst->intercept_dr_write = from->intercept_dr_write;
dst->intercept_exceptions = from->intercept_exceptions;
@@ -2188,8 +2197,8 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
nested_vmcb->control.event_inj,
nested_vmcb->control.nested_ctl);

- trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr_read,
- nested_vmcb->control.intercept_cr_write,
+ trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr & 0xffff,
+ nested_vmcb->control.intercept_cr >> 16,
nested_vmcb->control.intercept_exceptions,
nested_vmcb->control.intercept);

@@ -2269,8 +2278,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
svm->nested.vmcb_iopm = nested_vmcb->control.iopm_base_pa & ~0x0fffULL;

/* cache intercepts */
- svm->nested.intercept_cr_read = nested_vmcb->control.intercept_cr_read;
- svm->nested.intercept_cr_write = nested_vmcb->control.intercept_cr_write;
+ svm->nested.intercept_cr = nested_vmcb->control.intercept_cr;
svm->nested.intercept_dr_read = nested_vmcb->control.intercept_dr_read;
svm->nested.intercept_dr_write = nested_vmcb->control.intercept_dr_write;
svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions;
@@ -2285,8 +2293,8 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)

if (svm->vcpu.arch.hflags & HF_VINTR_MASK) {
/* We only want the cr8 intercept bits of the guest */
- svm->vmcb->control.intercept_cr_read &= ~INTERCEPT_CR8_MASK;
- svm->vmcb->control.intercept_cr_write &= ~INTERCEPT_CR8_MASK;
+ clr_cr_intercept(svm, INTERCEPT_CR8_READ);
+ clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
}

/* We don't want to see VMMCALLs from a nested guest */
@@ -2578,7 +2586,7 @@ static int cr8_write_interception(struct vcpu_svm *svm)
/* instruction emulation calls kvm_set_cr8() */
emulate_instruction(&svm->vcpu, 0, 0, 0);
if (irqchip_in_kernel(svm->vcpu.kvm)) {
- svm->vmcb->control.intercept_cr_write &= ~INTERCEPT_CR8_MASK;
+ clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
return 1;
}
if (cr8_prev <= kvm_get_cr8(&svm->vcpu))
@@ -2895,8 +2903,8 @@ void dump_vmcb(struct kvm_vcpu *vcpu)
struct vmcb_save_area *save = &svm->vmcb->save;

pr_err("VMCB Control Area:\n");
- pr_err("cr_read: %04x\n", control->intercept_cr_read);
- pr_err("cr_write: %04x\n", control->intercept_cr_write);
+ pr_err("cr_read: %04x\n", control->intercept_cr & 0xffff);
+ pr_err("cr_write: %04x\n", control->intercept_cr >> 16);
pr_err("dr_read: %04x\n", control->intercept_dr_read);
pr_err("dr_write: %04x\n", control->intercept_dr_write);
pr_err("exceptions: %08x\n", control->intercept_exceptions);
@@ -2997,7 +3005,7 @@ static int handle_exit(struct kvm_vcpu *vcpu)

trace_kvm_exit(exit_code, vcpu, KVM_ISA_SVM);

- if (!(svm->vmcb->control.intercept_cr_write & INTERCEPT_CR0_MASK))
+ if (!is_cr_intercept(svm, INTERCEPT_CR0_WRITE))
vcpu->arch.cr0 = svm->vmcb->save.cr0;
if (npt_enabled)
vcpu->arch.cr3 = svm->vmcb->save.cr3;
@@ -3123,7 +3131,7 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
return;

if (tpr >= irr)
- svm->vmcb->control.intercept_cr_write |= INTERCEPT_CR8_MASK;
+ set_cr_intercept(svm, INTERCEPT_CR8_WRITE);
}

static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
@@ -3230,7 +3238,7 @@ static inline void sync_cr8_to_lapic(struct kvm_vcpu *vcpu)
if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
return;

- if (!(svm->vmcb->control.intercept_cr_write & INTERCEPT_CR8_MASK)) {
+ if (!is_cr_intercept(svm, INTERCEPT_CR8_WRITE)) {
int cr8 = svm->vmcb->control.int_ctl & V_TPR_MASK;
kvm_set_cr8(vcpu, cr8);
}
--
1.7.1


--
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