diff options
Diffstat (limited to 'arch/x86/kvm/regs.h')
| -rw-r--r-- | arch/x86/kvm/regs.h | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/arch/x86/kvm/regs.h b/arch/x86/kvm/regs.h new file mode 100644 index 000000000..447f0ec3e --- /dev/null +++ b/arch/x86/kvm/regs.h @@ -0,0 +1,521 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef ARCH_X86_KVM_REGS_H +#define ARCH_X86_KVM_REGS_H + +#include <linux/kvm_host.h> + +#define KVM_POSSIBLE_CR0_GUEST_BITS (X86_CR0_TS | X86_CR0_WP) +#define KVM_POSSIBLE_CR4_GUEST_BITS \ + (X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR \ + | X86_CR4_OSXMMEXCPT | X86_CR4_PGE | X86_CR4_TSD | X86_CR4_FSGSBASE \ + | X86_CR4_CET) + +#define X86_CR0_PDPTR_BITS (X86_CR0_CD | X86_CR0_NW | X86_CR0_PG) +#define X86_CR4_TLBFLUSH_BITS (X86_CR4_PGE | X86_CR4_PCIDE | X86_CR4_PAE | X86_CR4_SMEP) +#define X86_CR4_PDPTR_BITS (X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_SMEP) + +static_assert(!(KVM_POSSIBLE_CR0_GUEST_BITS & X86_CR0_PDPTR_BITS)); + +#define CR0_RESERVED_BITS \ + (~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \ + | X86_CR0_ET | X86_CR0_NE | X86_CR0_WP | X86_CR0_AM \ + | X86_CR0_NW | X86_CR0_CD | X86_CR0_PG)) + +#define CR4_RESERVED_BITS \ + (~(unsigned long)(X86_CR4_VME | X86_CR4_PVI | X86_CR4_TSD | X86_CR4_DE\ + | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_MCE \ + | X86_CR4_PGE | X86_CR4_PCE | X86_CR4_OSFXSR | X86_CR4_PCIDE \ + | X86_CR4_OSXSAVE | X86_CR4_SMEP | X86_CR4_FSGSBASE \ + | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_VMXE \ + | X86_CR4_SMAP | X86_CR4_PKE | X86_CR4_UMIP \ + | X86_CR4_LAM_SUP | X86_CR4_CET)) + +#define CR8_RESERVED_BITS (~(unsigned long)X86_CR8_TPR) + +#define DR6_BUS_LOCK (1 << 11) +#define DR6_BD (1 << 13) +#define DR6_BS (1 << 14) +#define DR6_BT (1 << 15) +#define DR6_RTM (1 << 16) +/* + * DR6_ACTIVE_LOW combines fixed-1 and active-low bits. + * We can regard all the bits in DR6_FIXED_1 as active_low bits; + * they will never be 0 for now, but when they are defined + * in the future it will require no code change. + * + * DR6_ACTIVE_LOW is also used as the init/reset value for DR6. + */ +#define DR6_ACTIVE_LOW 0xffff0ff0 +#define DR6_VOLATILE 0x0001e80f +#define DR6_FIXED_1 (DR6_ACTIVE_LOW & ~DR6_VOLATILE) + +#define DR7_BP_EN_MASK 0x000000ff +#define DR7_GE (1 << 9) +#define DR7_GD (1 << 13) +#define DR7_VOLATILE 0xffff2bff + +void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0); +void kvm_post_set_cr4(struct kvm_vcpu *vcpu, unsigned long old_cr4, unsigned long cr4); +int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0); +int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3); +int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4); +int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8); +int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val); +unsigned long kvm_get_dr(struct kvm_vcpu *vcpu, int dr); +unsigned long kvm_get_cr8(struct kvm_vcpu *vcpu); +void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw); +int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3); + +static inline bool is_long_mode(struct kvm_vcpu *vcpu) +{ +#ifdef CONFIG_X86_64 + return !!(vcpu->arch.efer & EFER_LMA); +#else + return false; +#endif +} + +static inline bool is_64_bit_mode(struct kvm_vcpu *vcpu) +{ + int cs_db, cs_l; + + WARN_ON_ONCE(vcpu->arch.guest_state_protected); + + if (!is_long_mode(vcpu)) + return false; + kvm_x86_call(get_cs_db_l_bits)(vcpu, &cs_db, &cs_l); + return cs_l; +} + +static inline bool is_64_bit_hypercall(struct kvm_vcpu *vcpu) +{ +#ifdef CONFIG_X86_64 + /* + * If running with protected guest state, the CS register is not + * accessible. The hypercall register values will have had to been + * provided in 64-bit mode, so assume the guest is in 64-bit. + */ + return vcpu->arch.guest_state_protected || is_64_bit_mode(vcpu); +#else + return false; +#endif +} + +static __always_inline unsigned long kvm_reg_mode_mask(struct kvm_vcpu *vcpu) +{ +#ifdef CONFIG_X86_64 + return is_64_bit_mode(vcpu) ? GENMASK(63, 0) : GENMASK(31, 0); +#else + return GENMASK(31, 0); +#endif +} + +#define __BUILD_KVM_GPR_ACCESSORS(lname, uname) \ +static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu) \ +{ \ + return vcpu->arch.regs[VCPU_REGS_##uname] & kvm_reg_mode_mask(vcpu); \ +} \ +static __always_inline unsigned long kvm_##lname##_read_raw(struct kvm_vcpu *vcpu) \ +{ \ + return vcpu->arch.regs[VCPU_REGS_##uname]; \ +} \ +static __always_inline void kvm_##lname##_write_raw(struct kvm_vcpu *vcpu, \ + unsigned long val) \ +{ \ + vcpu->arch.regs[VCPU_REGS_##uname] = val; \ +} +#define BUILD_KVM_GPR_ACCESSORS(lname, uname) \ +static __always_inline u32 kvm_e##lname##_read(struct kvm_vcpu *vcpu) \ +{ \ + return vcpu->arch.regs[VCPU_REGS_##uname]; \ +} \ +static __always_inline void kvm_e##lname##_write(struct kvm_vcpu *vcpu, u32 val) \ +{ \ + vcpu->arch.regs[VCPU_REGS_##uname] = val; \ +} \ +__BUILD_KVM_GPR_ACCESSORS(r##lname, uname) + +BUILD_KVM_GPR_ACCESSORS(ax, RAX) +BUILD_KVM_GPR_ACCESSORS(bx, RBX) +BUILD_KVM_GPR_ACCESSORS(cx, RCX) +BUILD_KVM_GPR_ACCESSORS(dx, RDX) +BUILD_KVM_GPR_ACCESSORS(bp, RBP) +BUILD_KVM_GPR_ACCESSORS(si, RSI) +BUILD_KVM_GPR_ACCESSORS(di, RDI) +#ifdef CONFIG_X86_64 +__BUILD_KVM_GPR_ACCESSORS(r8, R8) +__BUILD_KVM_GPR_ACCESSORS(r9, R9) +__BUILD_KVM_GPR_ACCESSORS(r10, R10) +__BUILD_KVM_GPR_ACCESSORS(r11, R11) +__BUILD_KVM_GPR_ACCESSORS(r12, R12) +__BUILD_KVM_GPR_ACCESSORS(r13, R13) +__BUILD_KVM_GPR_ACCESSORS(r14, R14) +__BUILD_KVM_GPR_ACCESSORS(r15, R15) +#endif + +/* + * Using the register cache from interrupt context is generally not allowed, as + * caching a register and marking it available/dirty can't be done atomically, + * i.e. accesses from interrupt context may clobber state or read stale data if + * the vCPU task is in the process of updating the cache. The exception is if + * KVM is handling a PMI IRQ/NMI VM-Exit, as that bound code sequence doesn't + * touch the cache, it runs after the cache is reset (post VM-Exit), and PMIs + * need to access several registers that are cacheable. + */ +#define kvm_assert_register_caching_allowed(vcpu) \ + lockdep_assert_once(in_task() || kvm_arch_pmi_in_guest(vcpu)) + +/* + * avail dirty + * 0 0 register in VMCS/VMCB + * 0 1 *INVALID* + * 1 0 register in vcpu->arch + * 1 1 register in vcpu->arch, needs to be stored back + */ +static inline bool kvm_register_is_available(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + return test_bit(reg, vcpu->arch.regs_avail); +} + +static inline bool kvm_register_is_dirty(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + return test_bit(reg, vcpu->arch.regs_dirty); +} + +static inline void kvm_register_mark_for_reload(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + __clear_bit(reg, vcpu->arch.regs_avail); + __clear_bit(reg, vcpu->arch.regs_dirty); +} + +static inline void kvm_register_mark_available(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + __set_bit(reg, vcpu->arch.regs_avail); +} + +static inline void kvm_register_mark_dirty(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + __set_bit(reg, vcpu->arch.regs_avail); + __set_bit(reg, vcpu->arch.regs_dirty); +} + +/* + * kvm_register_test_and_mark_available() is a special snowflake that uses an + * arch bitop directly to avoid the explicit instrumentation that comes with + * the generic bitops. This allows code that cannot be instrumented (noinstr + * functions), e.g. the low level VM-Enter/VM-Exit paths, to cache registers. + */ +static __always_inline bool kvm_register_test_and_mark_available(struct kvm_vcpu *vcpu, + enum kvm_reg reg) +{ + kvm_assert_register_caching_allowed(vcpu); + return arch___test_and_set_bit(reg, vcpu->arch.regs_avail); +} + +static __always_inline void kvm_clear_available_registers(struct kvm_vcpu *vcpu, + unsigned long clear_mask) +{ + BUILD_BUG_ON(sizeof(clear_mask) != sizeof(vcpu->arch.regs_avail[0])); + BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.regs_avail) != 1); + + /* + * Note the bitwise-AND! In practice, a straight write would also work + * as KVM initializes the mask to all ones and never clears registers + * that are eagerly synchronized. Using a bitwise-AND adds a bit of + * sanity checking as incorrectly marking an eagerly sync'd register + * unavailable will generate a WARN due to an unexpected cache request. + */ + vcpu->arch.regs_avail[0] &= ~clear_mask; +} + +static __always_inline void kvm_reset_dirty_registers(struct kvm_vcpu *vcpu) +{ + BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.regs_dirty) != 1); + vcpu->arch.regs_dirty[0] = 0; +} + +/* + * The "raw" register helpers are only for cases where the full 64 bits of a + * register are read/written irrespective of current vCPU mode. In other words, + * odds are good you shouldn't be using the raw variants. + */ +static inline unsigned long kvm_register_read_raw(struct kvm_vcpu *vcpu, int reg) +{ + if (WARN_ON_ONCE((unsigned int)reg >= NR_VCPU_GENERAL_PURPOSE_REGS)) + return 0; + + if (!kvm_register_is_available(vcpu, reg)) + kvm_x86_call(cache_reg)(vcpu, reg); + + return vcpu->arch.regs[reg]; +} + +static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, int reg) +{ + return kvm_register_read_raw(vcpu, reg) & kvm_reg_mode_mask(vcpu); +} + +static inline void kvm_register_write_raw(struct kvm_vcpu *vcpu, int reg, + unsigned long val) +{ + if (WARN_ON_ONCE((unsigned int)reg >= NR_VCPU_GENERAL_PURPOSE_REGS)) + return; + + vcpu->arch.regs[reg] = val; + kvm_register_mark_dirty(vcpu, reg); +} + +static inline void kvm_register_write(struct kvm_vcpu *vcpu, + int reg, unsigned long val) +{ + return kvm_register_write_raw(vcpu, reg, val & kvm_reg_mode_mask(vcpu)); +} + +static inline unsigned long kvm_rip_read(struct kvm_vcpu *vcpu) +{ + if (!kvm_register_is_available(vcpu, VCPU_REG_RIP)) + kvm_x86_call(cache_reg)(vcpu, VCPU_REG_RIP); + + return vcpu->arch.rip; +} + +static inline void kvm_rip_write(struct kvm_vcpu *vcpu, unsigned long val) +{ + vcpu->arch.rip = val; + kvm_register_mark_dirty(vcpu, VCPU_REG_RIP); +} + +static inline unsigned long kvm_rsp_read(struct kvm_vcpu *vcpu) +{ + return kvm_register_read_raw(vcpu, VCPU_REGS_RSP); +} + +static inline void kvm_rsp_write(struct kvm_vcpu *vcpu, unsigned long val) +{ + kvm_register_write_raw(vcpu, VCPU_REGS_RSP, val); +} + +static inline u64 kvm_read_edx_eax(struct kvm_vcpu *vcpu) +{ + return kvm_eax_read(vcpu) | (u64)(kvm_edx_read(vcpu)) << 32; +} + +static inline u64 kvm_pdptr_read(struct kvm_vcpu *vcpu, int index) +{ + might_sleep(); /* on svm */ + + if (!kvm_register_is_available(vcpu, VCPU_REG_PDPTR)) + kvm_x86_call(cache_reg)(vcpu, VCPU_REG_PDPTR); + + return vcpu->arch.pdptrs[index]; +} + +static inline void kvm_pdptr_write(struct kvm_vcpu *vcpu, int index, u64 value) +{ + vcpu->arch.pdptrs[index] = value; +} + +static inline ulong kvm_read_cr0_bits(struct kvm_vcpu *vcpu, ulong mask) +{ + ulong tmask = mask & KVM_POSSIBLE_CR0_GUEST_BITS; + if ((tmask & vcpu->arch.cr0_guest_owned_bits) && + !kvm_register_is_available(vcpu, VCPU_REG_CR0)) + kvm_x86_call(cache_reg)(vcpu, VCPU_REG_CR0); + return vcpu->arch.cr0 & mask; +} + +static __always_inline bool kvm_is_cr0_bit_set(struct kvm_vcpu *vcpu, + unsigned long cr0_bit) +{ + BUILD_BUG_ON(!is_power_of_2(cr0_bit)); + + return !!kvm_read_cr0_bits(vcpu, cr0_bit); +} + +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) +{ + ulong tmask = mask & KVM_POSSIBLE_CR4_GUEST_BITS; + if ((tmask & vcpu->arch.cr4_guest_owned_bits) && + !kvm_register_is_available(vcpu, VCPU_REG_CR4)) + kvm_x86_call(cache_reg)(vcpu, VCPU_REG_CR4); + return vcpu->arch.cr4 & mask; +} + +static __always_inline bool kvm_is_cr4_bit_set(struct kvm_vcpu *vcpu, + unsigned long cr4_bit) +{ + BUILD_BUG_ON(!is_power_of_2(cr4_bit)); + + return !!kvm_read_cr4_bits(vcpu, cr4_bit); +} + +static inline ulong kvm_read_cr3(struct kvm_vcpu *vcpu) +{ + if (!kvm_register_is_available(vcpu, VCPU_REG_CR3)) + kvm_x86_call(cache_reg)(vcpu, VCPU_REG_CR3); + return vcpu->arch.cr3; +} + +static inline ulong kvm_read_cr4(struct kvm_vcpu *vcpu) +{ + return kvm_read_cr4_bits(vcpu, ~0UL); +} + +static inline bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) +{ + return !(cr4 & vcpu->arch.cr4_guest_rsvd_bits); +} + +#define __cr4_reserved_bits(__cpu_has, __c) \ +({ \ + u64 __reserved_bits = CR4_RESERVED_BITS; \ + \ + if (!__cpu_has(__c, X86_FEATURE_XSAVE)) \ + __reserved_bits |= X86_CR4_OSXSAVE; \ + if (!__cpu_has(__c, X86_FEATURE_SMEP)) \ + __reserved_bits |= X86_CR4_SMEP; \ + if (!__cpu_has(__c, X86_FEATURE_SMAP)) \ + __reserved_bits |= X86_CR4_SMAP; \ + if (!__cpu_has(__c, X86_FEATURE_FSGSBASE)) \ + __reserved_bits |= X86_CR4_FSGSBASE; \ + if (!__cpu_has(__c, X86_FEATURE_PKU)) \ + __reserved_bits |= X86_CR4_PKE; \ + if (!__cpu_has(__c, X86_FEATURE_LA57)) \ + __reserved_bits |= X86_CR4_LA57; \ + if (!__cpu_has(__c, X86_FEATURE_UMIP)) \ + __reserved_bits |= X86_CR4_UMIP; \ + if (!__cpu_has(__c, X86_FEATURE_VMX)) \ + __reserved_bits |= X86_CR4_VMXE; \ + if (!__cpu_has(__c, X86_FEATURE_PCID)) \ + __reserved_bits |= X86_CR4_PCIDE; \ + if (!__cpu_has(__c, X86_FEATURE_LAM)) \ + __reserved_bits |= X86_CR4_LAM_SUP; \ + if (!__cpu_has(__c, X86_FEATURE_SHSTK) && \ + !__cpu_has(__c, X86_FEATURE_IBT)) \ + __reserved_bits |= X86_CR4_CET; \ + __reserved_bits; \ +}) + +static inline bool is_protmode(struct kvm_vcpu *vcpu) +{ + return kvm_is_cr0_bit_set(vcpu, X86_CR0_PE); +} + +static inline bool is_pae(struct kvm_vcpu *vcpu) +{ + return kvm_is_cr4_bit_set(vcpu, X86_CR4_PAE); +} + +static inline bool is_pse(struct kvm_vcpu *vcpu) +{ + return kvm_is_cr4_bit_set(vcpu, X86_CR4_PSE); +} + +static inline bool is_paging(struct kvm_vcpu *vcpu) +{ + return likely(kvm_is_cr0_bit_set(vcpu, X86_CR0_PG)); +} + +static inline bool is_pae_paging(struct kvm_vcpu *vcpu) +{ + return !is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu); +} + +static inline bool kvm_dr7_valid(u64 data) +{ + /* Bits [63:32] are reserved */ + return !(data >> 32); +} +static inline bool kvm_dr6_valid(u64 data) +{ + /* Bits [63:32] are reserved */ + return !(data >> 32); +} + +static inline unsigned long kvm_get_effective_dr7(struct kvm_vcpu *vcpu) +{ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) + return vcpu->arch.guest_debug_dr7; + + return vcpu->arch.dr7; +} + +static inline void enter_guest_mode(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hflags |= HF_GUEST_MASK; + vcpu->stat.guest_mode = 1; +} + +static inline void leave_guest_mode(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hflags &= ~HF_GUEST_MASK; + + if (vcpu->arch.load_eoi_exitmap_pending) { + vcpu->arch.load_eoi_exitmap_pending = false; + kvm_make_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu); + } + + vcpu->stat.guest_mode = 0; +} + +static inline bool is_guest_mode(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.hflags & HF_GUEST_MASK; +} + +static inline unsigned long kvm_get_segment_base(struct kvm_vcpu *vcpu, int seg) +{ + return kvm_x86_call(get_segment_base)(vcpu, seg); +} + +static inline void kvm_set_segment(struct kvm_vcpu *vcpu, + struct kvm_segment *var, int seg) +{ + kvm_x86_call(set_segment)(vcpu, var, seg); +} + +static inline void kvm_get_segment(struct kvm_vcpu *vcpu, + struct kvm_segment *var, int seg) +{ + kvm_x86_call(get_segment)(vcpu, var, seg); +} + +unsigned long kvm_get_linear_rip(struct kvm_vcpu *vcpu); +bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip); + +unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu); +void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags); +void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags); + +void kvm_vcpu_ioctl_x86_get_sregs2(struct kvm_vcpu *vcpu, + struct kvm_sregs2 *sregs2); +int kvm_vcpu_ioctl_x86_set_sregs2(struct kvm_vcpu *vcpu, + struct kvm_sregs2 *sregs2); + +void kvm_run_sync_regs_to_user(struct kvm_vcpu *vcpu); +int kvm_run_sync_regs_from_user(struct kvm_vcpu *vcpu); + +void kvm_update_dr0123(struct kvm_vcpu *vcpu); +void kvm_update_dr7(struct kvm_vcpu *vcpu); +int kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu, + struct kvm_debugregs *dbgregs); +int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu, + struct kvm_debugregs *dbgregs); + + +#endif |