diff options
Diffstat (limited to 'arch/x86/kvm/vmx/vmx_ops.h')
-rw-r--r-- | arch/x86/kvm/vmx/vmx_ops.h | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmx_ops.h b/arch/x86/kvm/vmx/vmx_ops.h new file mode 100644 index 0000000000..33af7b4c6e --- /dev/null +++ b/arch/x86/kvm/vmx/vmx_ops.h @@ -0,0 +1,369 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __KVM_X86_VMX_INSN_H +#define __KVM_X86_VMX_INSN_H + +#include <linux/nospec.h> + +#include <asm/vmx.h> + +#include "hyperv.h" +#include "vmcs.h" +#include "../x86.h" + +void vmread_error(unsigned long field); +void vmwrite_error(unsigned long field, unsigned long value); +void vmclear_error(struct vmcs *vmcs, u64 phys_addr); +void vmptrld_error(struct vmcs *vmcs, u64 phys_addr); +void invvpid_error(unsigned long ext, u16 vpid, gva_t gva); +void invept_error(unsigned long ext, u64 eptp, gpa_t gpa); + +#ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT +/* + * The VMREAD error trampoline _always_ uses the stack to pass parameters, even + * for 64-bit targets. Preserving all registers allows the VMREAD inline asm + * blob to avoid clobbering GPRs, which in turn allows the compiler to better + * optimize sequences of VMREADs. + * + * Declare the trampoline as an opaque label as it's not safe to call from C + * code; there is no way to tell the compiler to pass params on the stack for + * 64-bit targets. + * + * void vmread_error_trampoline(unsigned long field, bool fault); + */ +extern unsigned long vmread_error_trampoline; + +/* + * The second VMREAD error trampoline, called from the assembly trampoline, + * exists primarily to enable instrumentation for the VM-Fail path. + */ +void vmread_error_trampoline2(unsigned long field, bool fault); + +#endif + +static __always_inline void vmcs_check16(unsigned long field) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000, + "16-bit accessor invalid for 64-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001, + "16-bit accessor invalid for 64-bit high field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000, + "16-bit accessor invalid for 32-bit high field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000, + "16-bit accessor invalid for natural width field"); +} + +static __always_inline void vmcs_check32(unsigned long field) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0, + "32-bit accessor invalid for 16-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000, + "32-bit accessor invalid for 64-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001, + "32-bit accessor invalid for 64-bit high field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000, + "32-bit accessor invalid for natural width field"); +} + +static __always_inline void vmcs_check64(unsigned long field) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0, + "64-bit accessor invalid for 16-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001, + "64-bit accessor invalid for 64-bit high field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000, + "64-bit accessor invalid for 32-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000, + "64-bit accessor invalid for natural width field"); +} + +static __always_inline void vmcs_checkl(unsigned long field) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0, + "Natural width accessor invalid for 16-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000, + "Natural width accessor invalid for 64-bit field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001, + "Natural width accessor invalid for 64-bit high field"); + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000, + "Natural width accessor invalid for 32-bit field"); +} + +static __always_inline unsigned long __vmcs_readl(unsigned long field) +{ + unsigned long value; + +#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT + + asm_volatile_goto("1: vmread %[field], %[output]\n\t" + "jna %l[do_fail]\n\t" + + _ASM_EXTABLE(1b, %l[do_exception]) + + : [output] "=r" (value) + : [field] "r" (field) + : "cc" + : do_fail, do_exception); + + return value; + +do_fail: + instrumentation_begin(); + vmread_error(field); + instrumentation_end(); + return 0; + +do_exception: + kvm_spurious_fault(); + return 0; + +#else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ + + asm volatile("1: vmread %2, %1\n\t" + ".byte 0x3e\n\t" /* branch taken hint */ + "ja 3f\n\t" + + /* + * VMREAD failed. Push '0' for @fault, push the failing + * @field, and bounce through the trampoline to preserve + * volatile registers. + */ + "xorl %k1, %k1\n\t" + "2:\n\t" + "push %1\n\t" + "push %2\n\t" + "call vmread_error_trampoline\n\t" + + /* + * Unwind the stack. Note, the trampoline zeros out the + * memory for @fault so that the result is '0' on error. + */ + "pop %2\n\t" + "pop %1\n\t" + "3:\n\t" + + /* VMREAD faulted. As above, except push '1' for @fault. */ + _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %1) + + : ASM_CALL_CONSTRAINT, "=&r"(value) : "r"(field) : "cc"); + return value; + +#endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ +} + +static __always_inline u16 vmcs_read16(unsigned long field) +{ + vmcs_check16(field); + if (kvm_is_using_evmcs()) + return evmcs_read16(field); + return __vmcs_readl(field); +} + +static __always_inline u32 vmcs_read32(unsigned long field) +{ + vmcs_check32(field); + if (kvm_is_using_evmcs()) + return evmcs_read32(field); + return __vmcs_readl(field); +} + +static __always_inline u64 vmcs_read64(unsigned long field) +{ + vmcs_check64(field); + if (kvm_is_using_evmcs()) + return evmcs_read64(field); +#ifdef CONFIG_X86_64 + return __vmcs_readl(field); +#else + return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32); +#endif +} + +static __always_inline unsigned long vmcs_readl(unsigned long field) +{ + vmcs_checkl(field); + if (kvm_is_using_evmcs()) + return evmcs_read64(field); + return __vmcs_readl(field); +} + +#define vmx_asm1(insn, op1, error_args...) \ +do { \ + asm_volatile_goto("1: " __stringify(insn) " %0\n\t" \ + ".byte 0x2e\n\t" /* branch not taken hint */ \ + "jna %l[error]\n\t" \ + _ASM_EXTABLE(1b, %l[fault]) \ + : : op1 : "cc" : error, fault); \ + return; \ +error: \ + instrumentation_begin(); \ + insn##_error(error_args); \ + instrumentation_end(); \ + return; \ +fault: \ + kvm_spurious_fault(); \ +} while (0) + +#define vmx_asm2(insn, op1, op2, error_args...) \ +do { \ + asm_volatile_goto("1: " __stringify(insn) " %1, %0\n\t" \ + ".byte 0x2e\n\t" /* branch not taken hint */ \ + "jna %l[error]\n\t" \ + _ASM_EXTABLE(1b, %l[fault]) \ + : : op1, op2 : "cc" : error, fault); \ + return; \ +error: \ + instrumentation_begin(); \ + insn##_error(error_args); \ + instrumentation_end(); \ + return; \ +fault: \ + kvm_spurious_fault(); \ +} while (0) + +static __always_inline void __vmcs_writel(unsigned long field, unsigned long value) +{ + vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value); +} + +static __always_inline void vmcs_write16(unsigned long field, u16 value) +{ + vmcs_check16(field); + if (kvm_is_using_evmcs()) + return evmcs_write16(field, value); + + __vmcs_writel(field, value); +} + +static __always_inline void vmcs_write32(unsigned long field, u32 value) +{ + vmcs_check32(field); + if (kvm_is_using_evmcs()) + return evmcs_write32(field, value); + + __vmcs_writel(field, value); +} + +static __always_inline void vmcs_write64(unsigned long field, u64 value) +{ + vmcs_check64(field); + if (kvm_is_using_evmcs()) + return evmcs_write64(field, value); + + __vmcs_writel(field, value); +#ifndef CONFIG_X86_64 + __vmcs_writel(field+1, value >> 32); +#endif +} + +static __always_inline void vmcs_writel(unsigned long field, unsigned long value) +{ + vmcs_checkl(field); + if (kvm_is_using_evmcs()) + return evmcs_write64(field, value); + + __vmcs_writel(field, value); +} + +static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000, + "vmcs_clear_bits does not support 64-bit fields"); + if (kvm_is_using_evmcs()) + return evmcs_write32(field, evmcs_read32(field) & ~mask); + + __vmcs_writel(field, __vmcs_readl(field) & ~mask); +} + +static __always_inline void vmcs_set_bits(unsigned long field, u32 mask) +{ + BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000, + "vmcs_set_bits does not support 64-bit fields"); + if (kvm_is_using_evmcs()) + return evmcs_write32(field, evmcs_read32(field) | mask); + + __vmcs_writel(field, __vmcs_readl(field) | mask); +} + +static inline void vmcs_clear(struct vmcs *vmcs) +{ + u64 phys_addr = __pa(vmcs); + + vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr); +} + +static inline void vmcs_load(struct vmcs *vmcs) +{ + u64 phys_addr = __pa(vmcs); + + if (kvm_is_using_evmcs()) + return evmcs_load(phys_addr); + + vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr); +} + +static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva) +{ + struct { + u64 vpid : 16; + u64 rsvd : 48; + u64 gva; + } operand = { vpid, 0, gva }; + + vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva); +} + +static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa) +{ + struct { + u64 eptp, gpa; + } operand = {eptp, gpa}; + + vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa); +} + +static inline void vpid_sync_vcpu_single(int vpid) +{ + if (vpid == 0) + return; + + __invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0); +} + +static inline void vpid_sync_vcpu_global(void) +{ + __invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0); +} + +static inline void vpid_sync_context(int vpid) +{ + if (cpu_has_vmx_invvpid_single()) + vpid_sync_vcpu_single(vpid); + else if (vpid != 0) + vpid_sync_vcpu_global(); +} + +static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr) +{ + if (vpid == 0) + return; + + if (cpu_has_vmx_invvpid_individual_addr()) + __invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr); + else + vpid_sync_context(vpid); +} + +static inline void ept_sync_global(void) +{ + __invept(VMX_EPT_EXTENT_GLOBAL, 0, 0); +} + +static inline void ept_sync_context(u64 eptp) +{ + if (cpu_has_vmx_invept_context()) + __invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0); + else + ept_sync_global(); +} + +#endif /* __KVM_X86_VMX_INSN_H */ |