arch/x86/kvm/vmx/vmx_ops.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __KVM_X86_VMX_INSN_H
   3 #define __KVM_X86_VMX_INSN_H
   4
   5 #include <linux/nospec.h>
   6
   7 #include <asm/vmx.h>
   8
   9 #include "hyperv.h"
  10 #include "vmcs.h"
  11 #include "../x86.h"
  12
  13 void vmread_error(unsigned long field);
  14 void vmwrite_error(unsigned long field, unsigned long value);
  15 void vmclear_error(struct vmcs *vmcs, u64 phys_addr);
  16 void vmptrld_error(struct vmcs *vmcs, u64 phys_addr);
  17 void invvpid_error(unsigned long ext, u16 vpid, gva_t gva);
  18 void invept_error(unsigned long ext, u64 eptp, gpa_t gpa);
  19
  20 #ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
  21 /*
  22  * The VMREAD error trampoline _always_ uses the stack to pass parameters, even
  23  * for 64-bit targets.  Preserving all registers allows the VMREAD inline asm
  24  * blob to avoid clobbering GPRs, which in turn allows the compiler to better
  25  * optimize sequences of VMREADs.
  26  *
  27  * Declare the trampoline as an opaque label as it's not safe to call from C
  28  * code; there is no way to tell the compiler to pass params on the stack for
  29  * 64-bit targets.
  30  *
  31  * void vmread_error_trampoline(unsigned long field, bool fault);
  32  */
  33 extern unsigned long vmread_error_trampoline;
  34
  35 /*
  36  * The second VMREAD error trampoline, called from the assembly trampoline,
  37  * exists primarily to enable instrumentation for the VM-Fail path.
  38  */
  39 void vmread_error_trampoline2(unsigned long field, bool fault);
  40
  41 #endif
  42
  43 static __always_inline void vmcs_check16(unsigned long field)
  44 {
  45         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
  46                          "16-bit accessor invalid for 64-bit field");
  47         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
  48                          "16-bit accessor invalid for 64-bit high field");
  49         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
  50                          "16-bit accessor invalid for 32-bit high field");
  51         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
  52                          "16-bit accessor invalid for natural width field");
  53 }
  54
  55 static __always_inline void vmcs_check32(unsigned long field)
  56 {
  57         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
  58                          "32-bit accessor invalid for 16-bit field");
  59         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
  60                          "32-bit accessor invalid for 64-bit field");
  61         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
  62                          "32-bit accessor invalid for 64-bit high field");
  63         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
  64                          "32-bit accessor invalid for natural width field");
  65 }
  66
  67 static __always_inline void vmcs_check64(unsigned long field)
  68 {
  69         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
  70                          "64-bit accessor invalid for 16-bit field");
  71         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
  72                          "64-bit accessor invalid for 64-bit high field");
  73         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
  74                          "64-bit accessor invalid for 32-bit field");
  75         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
  76                          "64-bit accessor invalid for natural width field");
  77 }
  78
  79 static __always_inline void vmcs_checkl(unsigned long field)
  80 {
  81         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
  82                          "Natural width accessor invalid for 16-bit field");
  83         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
  84                          "Natural width accessor invalid for 64-bit field");
  85         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
  86                          "Natural width accessor invalid for 64-bit high field");
  87         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
  88                          "Natural width accessor invalid for 32-bit field");
  89 }
  90
  91 static __always_inline unsigned long __vmcs_readl(unsigned long field)
  92 {
  93         unsigned long value;
  94
  95 #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
  96
  97         asm_volatile_goto("1: vmread %[field], %[output]\n\t"
  98                           "jna %l[do_fail]\n\t"
  99
 100                           _ASM_EXTABLE(1b, %l[do_exception])
 101
 102                           : [output] "=r" (value)
 103                           : [field] "r" (field)
 104                           : "cc"
 105                           : do_fail, do_exception);
 106
 107         return value;
 108
 109 do_fail:
 110         instrumentation_begin();
 111         vmread_error(field);
 112         instrumentation_end();
 113         return 0;
 114
 115 do_exception:
 116         kvm_spurious_fault();
 117         return 0;
 118
 119 #else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
 120
 121         asm volatile("1: vmread %2, %1\n\t"
 122                      ".byte 0x3e\n\t" /* branch taken hint */
 123                      "ja 3f\n\t"
 124
 125                      /*
 126                       * VMREAD failed.  Push '0' for @fault, push the failing
 127                       * @field, and bounce through the trampoline to preserve
 128                       * volatile registers.
 129                       */
 130                      "xorl %k1, %k1\n\t"
 131                      "2:\n\t"
 132                      "push %1\n\t"
 133                      "push %2\n\t"
 134                      "call vmread_error_trampoline\n\t"
 135
 136                      /*
 137                       * Unwind the stack.  Note, the trampoline zeros out the
 138                       * memory for @fault so that the result is '0' on error.
 139                       */
 140                      "pop %2\n\t"
 141                      "pop %1\n\t"
 142                      "3:\n\t"
 143
 144                      /* VMREAD faulted.  As above, except push '1' for @fault. */
 145                      _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %1)
 146
 147                      : ASM_CALL_CONSTRAINT, "=&r"(value) : "r"(field) : "cc");
 148         return value;
 149
 150 #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
 151 }
 152
 153 static __always_inline u16 vmcs_read16(unsigned long field)
 154 {
 155         vmcs_check16(field);
 156         if (kvm_is_using_evmcs())
 157                 return evmcs_read16(field);
 158         return __vmcs_readl(field);
 159 }
 160
 161 static __always_inline u32 vmcs_read32(unsigned long field)
 162 {
 163         vmcs_check32(field);
 164         if (kvm_is_using_evmcs())
 165                 return evmcs_read32(field);
 166         return __vmcs_readl(field);
 167 }
 168
 169 static __always_inline u64 vmcs_read64(unsigned long field)
 170 {
 171         vmcs_check64(field);
 172         if (kvm_is_using_evmcs())
 173                 return evmcs_read64(field);
 174 #ifdef CONFIG_X86_64
 175         return __vmcs_readl(field);
 176 #else
 177         return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
 178 #endif
 179 }
 180
 181 static __always_inline unsigned long vmcs_readl(unsigned long field)
 182 {
 183         vmcs_checkl(field);
 184         if (kvm_is_using_evmcs())
 185                 return evmcs_read64(field);
 186         return __vmcs_readl(field);
 187 }
 188
 189 #define vmx_asm1(insn, op1, error_args...)                              \
 190 do {                                                                    \
 191         asm_volatile_goto("1: " __stringify(insn) " %0\n\t"             \
 192                           ".byte 0x2e\n\t" /* branch not taken hint */  \
 193                           "jna %l[error]\n\t"                           \
 194                           _ASM_EXTABLE(1b, %l[fault])                   \
 195                           : : op1 : "cc" : error, fault);               \
 196         return;                                                         \
 197 error:                                                                  \
 198         instrumentation_begin();                                        \
 199         insn##_error(error_args);                                       \
 200         instrumentation_end();                                          \
 201         return;                                                         \
 202 fault:                                                                  \
 203         kvm_spurious_fault();                                           \
 204 } while (0)
 205
 206 #define vmx_asm2(insn, op1, op2, error_args...)                         \
 207 do {                                                                    \
 208         asm_volatile_goto("1: "  __stringify(insn) " %1, %0\n\t"        \
 209                           ".byte 0x2e\n\t" /* branch not taken hint */  \
 210                           "jna %l[error]\n\t"                           \
 211                           _ASM_EXTABLE(1b, %l[fault])                   \
 212                           : : op1, op2 : "cc" : error, fault);          \
 213         return;                                                         \
 214 error:                                                                  \
 215         instrumentation_begin();                                        \
 216         insn##_error(error_args);                                       \
 217         instrumentation_end();                                          \
 218         return;                                                         \
 219 fault:                                                                  \
 220         kvm_spurious_fault();                                           \
 221 } while (0)
 222
 223 static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
 224 {
 225         vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
 226 }
 227
 228 static __always_inline void vmcs_write16(unsigned long field, u16 value)
 229 {
 230         vmcs_check16(field);
 231         if (kvm_is_using_evmcs())
 232                 return evmcs_write16(field, value);
 233
 234         __vmcs_writel(field, value);
 235 }
 236
 237 static __always_inline void vmcs_write32(unsigned long field, u32 value)
 238 {
 239         vmcs_check32(field);
 240         if (kvm_is_using_evmcs())
 241                 return evmcs_write32(field, value);
 242
 243         __vmcs_writel(field, value);
 244 }
 245
 246 static __always_inline void vmcs_write64(unsigned long field, u64 value)
 247 {
 248         vmcs_check64(field);
 249         if (kvm_is_using_evmcs())
 250                 return evmcs_write64(field, value);
 251
 252         __vmcs_writel(field, value);
 253 #ifndef CONFIG_X86_64
 254         __vmcs_writel(field+1, value >> 32);
 255 #endif
 256 }
 257
 258 static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
 259 {
 260         vmcs_checkl(field);
 261         if (kvm_is_using_evmcs())
 262                 return evmcs_write64(field, value);
 263
 264         __vmcs_writel(field, value);
 265 }
 266
 267 static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
 268 {
 269         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
 270                          "vmcs_clear_bits does not support 64-bit fields");
 271         if (kvm_is_using_evmcs())
 272                 return evmcs_write32(field, evmcs_read32(field) & ~mask);
 273
 274         __vmcs_writel(field, __vmcs_readl(field) & ~mask);
 275 }
 276
 277 static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
 278 {
 279         BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
 280                          "vmcs_set_bits does not support 64-bit fields");
 281         if (kvm_is_using_evmcs())
 282                 return evmcs_write32(field, evmcs_read32(field) | mask);
 283
 284         __vmcs_writel(field, __vmcs_readl(field) | mask);
 285 }
 286
 287 static inline void vmcs_clear(struct vmcs *vmcs)
 288 {
 289         u64 phys_addr = __pa(vmcs);
 290
 291         vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
 292 }
 293
 294 static inline void vmcs_load(struct vmcs *vmcs)
 295 {
 296         u64 phys_addr = __pa(vmcs);
 297
 298         if (kvm_is_using_evmcs())
 299                 return evmcs_load(phys_addr);
 300
 301         vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
 302 }
 303
 304 static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
 305 {
 306         struct {
 307                 u64 vpid : 16;
 308                 u64 rsvd : 48;
 309                 u64 gva;
 310         } operand = { vpid, 0, gva };
 311
 312         vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
 313 }
 314
 315 static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
 316 {
 317         struct {
 318                 u64 eptp, gpa;
 319         } operand = {eptp, gpa};
 320
 321         vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa);
 322 }
 323
 324 static inline void vpid_sync_vcpu_single(int vpid)
 325 {
 326         if (vpid == 0)
 327                 return;
 328
 329         __invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
 330 }
 331
 332 static inline void vpid_sync_vcpu_global(void)
 333 {
 334         __invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
 335 }
 336
 337 static inline void vpid_sync_context(int vpid)
 338 {
 339         if (cpu_has_vmx_invvpid_single())
 340                 vpid_sync_vcpu_single(vpid);
 341         else if (vpid != 0)
 342                 vpid_sync_vcpu_global();
 343 }
 344
 345 static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
 346 {
 347         if (vpid == 0)
 348                 return;
 349
 350         if (cpu_has_vmx_invvpid_individual_addr())
 351                 __invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
 352         else
 353                 vpid_sync_context(vpid);
 354 }
 355
 356 static inline void ept_sync_global(void)
 357 {
 358         __invept(VMX_EPT_EXTENT_GLOBAL, 0, 0);
 359 }
 360
 361 static inline void ept_sync_context(u64 eptp)
 362 {
 363         if (cpu_has_vmx_invept_context())
 364                 __invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0);
 365         else
 366                 ept_sync_global();
 367 }
 368
 369 #endif /* __KVM_X86_VMX_INSN_H */