KVM: SVM: Add manipulation functions for CRx intercepts

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@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

2 files changed, 73 insertions, 62 deletions

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 0e831059ac5a..39f9ddf07136 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 74f89f0b9e3f..1e7bb9c77084 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);
         }
 }
 
@@ -1901,15 +1917,9 @@ 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;
         }
@@ -1966,8 +1976,7 @@ 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;
@@ -2189,8 +2198,8 @@ 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);
 
@@ -2270,8 +2279,7 @@ 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;
@@ -2286,8 +2294,8 @@ 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 */
@@ -2579,7 +2587,7 @@ 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))
@@ -2896,8 +2904,8 @@ 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);
@@ -2998,7 +3006,7 @@ 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;
@@ -3124,7 +3132,7 @@ 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)
@@ -3231,7 +3239,7 @@ 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);
         }