From 2dafc6c234b6064189405f42e1602e9a0abe5a44 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Thu, 18 Mar 2010 15:20:16 +0200 Subject: [PATCH] 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 Signed-off-by: Marcelo Tosatti --- arch/x86/include/asm/kvm_emulate.h | 16 ++++ arch/x86/kvm/x86.c | 130 +++++++++++++++++++++++++---- 2 files changed, 131 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 07657258af8f..f901467a18b0 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -62,6 +62,15 @@ struct x86_emulate_ops { int (*read_std)(unsigned long addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, u32 *error); + /* + * write_std: Write bytes of standard (non-emulated/special) memory. + * Used for descriptor writing. + * @addr: [IN ] Linear address to which to write. + * @val: [OUT] Value write to memory, zero-extended to 'u_long'. + * @bytes: [IN ] Number of bytes to write to memory. + */ + int (*write_std)(unsigned long addr, void *val, + unsigned int bytes, struct kvm_vcpu *vcpu, u32 *error); /* * fetch: Read bytes of standard (non-emulated/special) memory. * Used for instruction fetch. @@ -108,6 +117,13 @@ struct x86_emulate_ops { const void *new, unsigned int bytes, struct kvm_vcpu *vcpu); + bool (*get_cached_descriptor)(struct desc_struct *desc, + int seg, struct kvm_vcpu *vcpu); + void (*set_cached_descriptor)(struct desc_struct *desc, + int seg, struct kvm_vcpu *vcpu); + u16 (*get_segment_selector)(int seg, struct kvm_vcpu *vcpu); + void (*set_segment_selector)(u16 sel, int seg, struct kvm_vcpu *vcpu); + void (*get_gdt)(struct desc_ptr *dt, struct kvm_vcpu *vcpu); ulong (*get_cr)(int cr, struct kvm_vcpu *vcpu); void (*set_cr)(int cr, ulong val, struct kvm_vcpu *vcpu); int (*cpl)(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0ecd37ac9d39..fbee8fbb33b5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3058,6 +3058,18 @@ static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v) 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 @@ static int kvm_read_guest_virt_system(gva_t addr, void *val, unsigned int bytes, 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 @@ static int kvm_write_guest_virt(gva_t addr, void *val, unsigned int bytes, 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 @@ static int emulator_get_cpl(struct kvm_vcpu *vcpu) 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 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) 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 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 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) { -- GitLab