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