KVM: x86 emulator: Provide more callbacks for x86 emulator.
Provide get_cached_descriptor(), set_cached_descriptor(),
get_segment_selector(), set_segment_selector(), get_gdt(),
write_std() callbacks.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0ecd37a..fbee8fb 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3058,6 +3058,18 @@
return kvm_io_bus_read(vcpu->kvm, KVM_MMIO_BUS, addr, len, v);
}
+static void kvm_set_segment(struct kvm_vcpu *vcpu,
+ struct kvm_segment *var, int seg)
+{
+ kvm_x86_ops->set_segment(vcpu, var, seg);
+}
+
+void kvm_get_segment(struct kvm_vcpu *vcpu,
+ struct kvm_segment *var, int seg)
+{
+ kvm_x86_ops->get_segment(vcpu, var, seg);
+}
+
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva, u32 *error)
{
u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
@@ -3138,14 +3150,18 @@
return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, error);
}
-static int kvm_write_guest_virt(gva_t addr, void *val, unsigned int bytes,
- struct kvm_vcpu *vcpu, u32 *error)
+static int kvm_write_guest_virt_helper(gva_t addr, void *val,
+ unsigned int bytes,
+ struct kvm_vcpu *vcpu, u32 access,
+ u32 *error)
{
void *data = val;
int r = X86EMUL_CONTINUE;
+ access |= PFERR_WRITE_MASK;
+
while (bytes) {
- gpa_t gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, error);
+ gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, addr, access, error);
unsigned offset = addr & (PAGE_SIZE-1);
unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
int ret;
@@ -3168,6 +3184,19 @@
return r;
}
+static int kvm_write_guest_virt(gva_t addr, void *val, unsigned int bytes,
+ struct kvm_vcpu *vcpu, u32 *error)
+{
+ u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
+ return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, access, error);
+}
+
+static int kvm_write_guest_virt_system(gva_t addr, void *val,
+ unsigned int bytes,
+ struct kvm_vcpu *vcpu, u32 *error)
+{
+ return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, 0, error);
+}
static int emulator_read_emulated(unsigned long addr,
void *val,
@@ -3484,12 +3513,95 @@
return kvm_x86_ops->get_cpl(vcpu);
}
+static void emulator_get_gdt(struct desc_ptr *dt, struct kvm_vcpu *vcpu)
+{
+ kvm_x86_ops->get_gdt(vcpu, dt);
+}
+
+static bool emulator_get_cached_descriptor(struct desc_struct *desc, int seg,
+ struct kvm_vcpu *vcpu)
+{
+ struct kvm_segment var;
+
+ kvm_get_segment(vcpu, &var, seg);
+
+ if (var.unusable)
+ return false;
+
+ if (var.g)
+ var.limit >>= 12;
+ set_desc_limit(desc, var.limit);
+ set_desc_base(desc, (unsigned long)var.base);
+ desc->type = var.type;
+ desc->s = var.s;
+ desc->dpl = var.dpl;
+ desc->p = var.present;
+ desc->avl = var.avl;
+ desc->l = var.l;
+ desc->d = var.db;
+ desc->g = var.g;
+
+ return true;
+}
+
+static void emulator_set_cached_descriptor(struct desc_struct *desc, int seg,
+ struct kvm_vcpu *vcpu)
+{
+ struct kvm_segment var;
+
+ /* needed to preserve selector */
+ kvm_get_segment(vcpu, &var, seg);
+
+ var.base = get_desc_base(desc);
+ var.limit = get_desc_limit(desc);
+ if (desc->g)
+ var.limit = (var.limit << 12) | 0xfff;
+ var.type = desc->type;
+ var.present = desc->p;
+ var.dpl = desc->dpl;
+ var.db = desc->d;
+ var.s = desc->s;
+ var.l = desc->l;
+ var.g = desc->g;
+ var.avl = desc->avl;
+ var.present = desc->p;
+ var.unusable = !var.present;
+ var.padding = 0;
+
+ kvm_set_segment(vcpu, &var, seg);
+ return;
+}
+
+static u16 emulator_get_segment_selector(int seg, struct kvm_vcpu *vcpu)
+{
+ struct kvm_segment kvm_seg;
+
+ kvm_get_segment(vcpu, &kvm_seg, seg);
+ return kvm_seg.selector;
+}
+
+static void emulator_set_segment_selector(u16 sel, int seg,
+ struct kvm_vcpu *vcpu)
+{
+ struct kvm_segment kvm_seg;
+
+ kvm_get_segment(vcpu, &kvm_seg, seg);
+ kvm_seg.selector = sel;
+ kvm_set_segment(vcpu, &kvm_seg, seg);
+}
+
static struct x86_emulate_ops emulate_ops = {
.read_std = kvm_read_guest_virt_system,
+ .write_std = kvm_write_guest_virt_system,
.fetch = kvm_fetch_guest_virt,
.read_emulated = emulator_read_emulated,
.write_emulated = emulator_write_emulated,
.cmpxchg_emulated = emulator_cmpxchg_emulated,
+ .get_cached_descriptor = emulator_get_cached_descriptor,
+ .set_cached_descriptor = emulator_set_cached_descriptor,
+ .get_segment_selector = emulator_get_segment_selector,
+ .set_segment_selector = emulator_set_segment_selector,
+ .get_gdt = emulator_get_gdt,
.get_cr = emulator_get_cr,
.set_cr = emulator_set_cr,
.cpl = emulator_get_cpl,
@@ -4649,12 +4761,6 @@
return 0;
}
-void kvm_get_segment(struct kvm_vcpu *vcpu,
- struct kvm_segment *var, int seg)
-{
- kvm_x86_ops->get_segment(vcpu, var, seg);
-}
-
void kvm_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
{
struct kvm_segment cs;
@@ -4726,12 +4832,6 @@
return 0;
}
-static void kvm_set_segment(struct kvm_vcpu *vcpu,
- struct kvm_segment *var, int seg)
-{
- kvm_x86_ops->set_segment(vcpu, var, seg);
-}
-
static void seg_desct_to_kvm_desct(struct desc_struct *seg_desc, u16 selector,
struct kvm_segment *kvm_desct)
{