xref: /openbmc/linux/arch/x86/kvm/x86.h (revision 88021836)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef ARCH_X86_KVM_X86_H
3 #define ARCH_X86_KVM_X86_H
4 
5 #include <linux/kvm_host.h>
6 #include <asm/fpu/xstate.h>
7 #include <asm/mce.h>
8 #include <asm/pvclock.h>
9 #include "kvm_cache_regs.h"
10 #include "kvm_emulate.h"
11 
12 struct kvm_caps {
13 	/* control of guest tsc rate supported? */
14 	bool has_tsc_control;
15 	/* maximum supported tsc_khz for guests */
16 	u32  max_guest_tsc_khz;
17 	/* number of bits of the fractional part of the TSC scaling ratio */
18 	u8   tsc_scaling_ratio_frac_bits;
19 	/* maximum allowed value of TSC scaling ratio */
20 	u64  max_tsc_scaling_ratio;
21 	/* 1ull << kvm_caps.tsc_scaling_ratio_frac_bits */
22 	u64  default_tsc_scaling_ratio;
23 	/* bus lock detection supported? */
24 	bool has_bus_lock_exit;
25 	/* notify VM exit supported? */
26 	bool has_notify_vmexit;
27 
28 	u64 supported_mce_cap;
29 	u64 supported_xcr0;
30 	u64 supported_xss;
31 	u64 supported_perf_cap;
32 };
33 
34 void kvm_spurious_fault(void);
35 
36 #define KVM_NESTED_VMENTER_CONSISTENCY_CHECK(consistency_check)		\
37 ({									\
38 	bool failed = (consistency_check);				\
39 	if (failed)							\
40 		trace_kvm_nested_vmenter_failed(#consistency_check, 0);	\
41 	failed;								\
42 })
43 
44 /*
45  * The first...last VMX feature MSRs that are emulated by KVM.  This may or may
46  * not cover all known VMX MSRs, as KVM doesn't emulate an MSR until there's an
47  * associated feature that KVM supports for nested virtualization.
48  */
49 #define KVM_FIRST_EMULATED_VMX_MSR	MSR_IA32_VMX_BASIC
50 #define KVM_LAST_EMULATED_VMX_MSR	MSR_IA32_VMX_VMFUNC
51 
52 #define KVM_DEFAULT_PLE_GAP		128
53 #define KVM_VMX_DEFAULT_PLE_WINDOW	4096
54 #define KVM_DEFAULT_PLE_WINDOW_GROW	2
55 #define KVM_DEFAULT_PLE_WINDOW_SHRINK	0
56 #define KVM_VMX_DEFAULT_PLE_WINDOW_MAX	UINT_MAX
57 #define KVM_SVM_DEFAULT_PLE_WINDOW_MAX	USHRT_MAX
58 #define KVM_SVM_DEFAULT_PLE_WINDOW	3000
59 
60 static inline unsigned int __grow_ple_window(unsigned int val,
61 		unsigned int base, unsigned int modifier, unsigned int max)
62 {
63 	u64 ret = val;
64 
65 	if (modifier < 1)
66 		return base;
67 
68 	if (modifier < base)
69 		ret *= modifier;
70 	else
71 		ret += modifier;
72 
73 	return min(ret, (u64)max);
74 }
75 
76 static inline unsigned int __shrink_ple_window(unsigned int val,
77 		unsigned int base, unsigned int modifier, unsigned int min)
78 {
79 	if (modifier < 1)
80 		return base;
81 
82 	if (modifier < base)
83 		val /= modifier;
84 	else
85 		val -= modifier;
86 
87 	return max(val, min);
88 }
89 
90 #define MSR_IA32_CR_PAT_DEFAULT  0x0007040600070406ULL
91 
92 void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu);
93 int kvm_check_nested_events(struct kvm_vcpu *vcpu);
94 
95 static inline bool kvm_vcpu_has_run(struct kvm_vcpu *vcpu)
96 {
97 	return vcpu->arch.last_vmentry_cpu != -1;
98 }
99 
100 static inline bool kvm_is_exception_pending(struct kvm_vcpu *vcpu)
101 {
102 	return vcpu->arch.exception.pending ||
103 	       vcpu->arch.exception_vmexit.pending ||
104 	       kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu);
105 }
106 
107 static inline void kvm_clear_exception_queue(struct kvm_vcpu *vcpu)
108 {
109 	vcpu->arch.exception.pending = false;
110 	vcpu->arch.exception.injected = false;
111 	vcpu->arch.exception_vmexit.pending = false;
112 }
113 
114 static inline void kvm_queue_interrupt(struct kvm_vcpu *vcpu, u8 vector,
115 	bool soft)
116 {
117 	vcpu->arch.interrupt.injected = true;
118 	vcpu->arch.interrupt.soft = soft;
119 	vcpu->arch.interrupt.nr = vector;
120 }
121 
122 static inline void kvm_clear_interrupt_queue(struct kvm_vcpu *vcpu)
123 {
124 	vcpu->arch.interrupt.injected = false;
125 }
126 
127 static inline bool kvm_event_needs_reinjection(struct kvm_vcpu *vcpu)
128 {
129 	return vcpu->arch.exception.injected || vcpu->arch.interrupt.injected ||
130 		vcpu->arch.nmi_injected;
131 }
132 
133 static inline bool kvm_exception_is_soft(unsigned int nr)
134 {
135 	return (nr == BP_VECTOR) || (nr == OF_VECTOR);
136 }
137 
138 static inline bool is_protmode(struct kvm_vcpu *vcpu)
139 {
140 	return kvm_is_cr0_bit_set(vcpu, X86_CR0_PE);
141 }
142 
143 static inline bool is_long_mode(struct kvm_vcpu *vcpu)
144 {
145 #ifdef CONFIG_X86_64
146 	return !!(vcpu->arch.efer & EFER_LMA);
147 #else
148 	return false;
149 #endif
150 }
151 
152 static inline bool is_64_bit_mode(struct kvm_vcpu *vcpu)
153 {
154 	int cs_db, cs_l;
155 
156 	WARN_ON_ONCE(vcpu->arch.guest_state_protected);
157 
158 	if (!is_long_mode(vcpu))
159 		return false;
160 	static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
161 	return cs_l;
162 }
163 
164 static inline bool is_64_bit_hypercall(struct kvm_vcpu *vcpu)
165 {
166 	/*
167 	 * If running with protected guest state, the CS register is not
168 	 * accessible. The hypercall register values will have had to been
169 	 * provided in 64-bit mode, so assume the guest is in 64-bit.
170 	 */
171 	return vcpu->arch.guest_state_protected || is_64_bit_mode(vcpu);
172 }
173 
174 static inline bool x86_exception_has_error_code(unsigned int vector)
175 {
176 	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
177 			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
178 			BIT(PF_VECTOR) | BIT(AC_VECTOR);
179 
180 	return (1U << vector) & exception_has_error_code;
181 }
182 
183 static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
184 {
185 	return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;
186 }
187 
188 static inline bool is_pae(struct kvm_vcpu *vcpu)
189 {
190 	return kvm_is_cr4_bit_set(vcpu, X86_CR4_PAE);
191 }
192 
193 static inline bool is_pse(struct kvm_vcpu *vcpu)
194 {
195 	return kvm_is_cr4_bit_set(vcpu, X86_CR4_PSE);
196 }
197 
198 static inline bool is_paging(struct kvm_vcpu *vcpu)
199 {
200 	return likely(kvm_is_cr0_bit_set(vcpu, X86_CR0_PG));
201 }
202 
203 static inline bool is_pae_paging(struct kvm_vcpu *vcpu)
204 {
205 	return !is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu);
206 }
207 
208 static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu)
209 {
210 	return kvm_is_cr4_bit_set(vcpu, X86_CR4_LA57) ? 57 : 48;
211 }
212 
213 static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu)
214 {
215 	return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu));
216 }
217 
218 static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu,
219 					gva_t gva, gfn_t gfn, unsigned access)
220 {
221 	u64 gen = kvm_memslots(vcpu->kvm)->generation;
222 
223 	if (unlikely(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS))
224 		return;
225 
226 	/*
227 	 * If this is a shadow nested page table, the "GVA" is
228 	 * actually a nGPA.
229 	 */
230 	vcpu->arch.mmio_gva = mmu_is_nested(vcpu) ? 0 : gva & PAGE_MASK;
231 	vcpu->arch.mmio_access = access;
232 	vcpu->arch.mmio_gfn = gfn;
233 	vcpu->arch.mmio_gen = gen;
234 }
235 
236 static inline bool vcpu_match_mmio_gen(struct kvm_vcpu *vcpu)
237 {
238 	return vcpu->arch.mmio_gen == kvm_memslots(vcpu->kvm)->generation;
239 }
240 
241 /*
242  * Clear the mmio cache info for the given gva. If gva is MMIO_GVA_ANY, we
243  * clear all mmio cache info.
244  */
245 #define MMIO_GVA_ANY (~(gva_t)0)
246 
247 static inline void vcpu_clear_mmio_info(struct kvm_vcpu *vcpu, gva_t gva)
248 {
249 	if (gva != MMIO_GVA_ANY && vcpu->arch.mmio_gva != (gva & PAGE_MASK))
250 		return;
251 
252 	vcpu->arch.mmio_gva = 0;
253 }
254 
255 static inline bool vcpu_match_mmio_gva(struct kvm_vcpu *vcpu, unsigned long gva)
256 {
257 	if (vcpu_match_mmio_gen(vcpu) && vcpu->arch.mmio_gva &&
258 	      vcpu->arch.mmio_gva == (gva & PAGE_MASK))
259 		return true;
260 
261 	return false;
262 }
263 
264 static inline bool vcpu_match_mmio_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
265 {
266 	if (vcpu_match_mmio_gen(vcpu) && vcpu->arch.mmio_gfn &&
267 	      vcpu->arch.mmio_gfn == gpa >> PAGE_SHIFT)
268 		return true;
269 
270 	return false;
271 }
272 
273 static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, int reg)
274 {
275 	unsigned long val = kvm_register_read_raw(vcpu, reg);
276 
277 	return is_64_bit_mode(vcpu) ? val : (u32)val;
278 }
279 
280 static inline void kvm_register_write(struct kvm_vcpu *vcpu,
281 				       int reg, unsigned long val)
282 {
283 	if (!is_64_bit_mode(vcpu))
284 		val = (u32)val;
285 	return kvm_register_write_raw(vcpu, reg, val);
286 }
287 
288 static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk)
289 {
290 	return !(kvm->arch.disabled_quirks & quirk);
291 }
292 
293 void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip);
294 
295 u64 get_kvmclock_ns(struct kvm *kvm);
296 
297 int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
298 	gva_t addr, void *val, unsigned int bytes,
299 	struct x86_exception *exception);
300 
301 int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu,
302 	gva_t addr, void *val, unsigned int bytes,
303 	struct x86_exception *exception);
304 
305 int handle_ud(struct kvm_vcpu *vcpu);
306 
307 void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu,
308 				   struct kvm_queued_exception *ex);
309 
310 void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu);
311 u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn);
312 int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data);
313 int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
314 bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn,
315 					  int page_num);
316 bool kvm_vector_hashing_enabled(void);
317 void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code);
318 int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
319 				    void *insn, int insn_len);
320 int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
321 			    int emulation_type, void *insn, int insn_len);
322 fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu);
323 
324 extern u64 host_xcr0;
325 extern u64 host_xss;
326 
327 extern struct kvm_caps kvm_caps;
328 
329 extern bool enable_pmu;
330 
331 /*
332  * Get a filtered version of KVM's supported XCR0 that strips out dynamic
333  * features for which the current process doesn't (yet) have permission to use.
334  * This is intended to be used only when enumerating support to userspace,
335  * e.g. in KVM_GET_SUPPORTED_CPUID and KVM_CAP_XSAVE2, it does NOT need to be
336  * used to check/restrict guest behavior as KVM rejects KVM_SET_CPUID{2} if
337  * userspace attempts to enable unpermitted features.
338  */
339 static inline u64 kvm_get_filtered_xcr0(void)
340 {
341 	u64 permitted_xcr0 = kvm_caps.supported_xcr0;
342 
343 	BUILD_BUG_ON(XFEATURE_MASK_USER_DYNAMIC != XFEATURE_MASK_XTILE_DATA);
344 
345 	if (permitted_xcr0 & XFEATURE_MASK_USER_DYNAMIC) {
346 		permitted_xcr0 &= xstate_get_guest_group_perm();
347 
348 		/*
349 		 * Treat XTILE_CFG as unsupported if the current process isn't
350 		 * allowed to use XTILE_DATA, as attempting to set XTILE_CFG in
351 		 * XCR0 without setting XTILE_DATA is architecturally illegal.
352 		 */
353 		if (!(permitted_xcr0 & XFEATURE_MASK_XTILE_DATA))
354 			permitted_xcr0 &= ~XFEATURE_MASK_XTILE_CFG;
355 	}
356 	return permitted_xcr0;
357 }
358 
359 static inline bool kvm_mpx_supported(void)
360 {
361 	return (kvm_caps.supported_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
362 		== (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
363 }
364 
365 extern unsigned int min_timer_period_us;
366 
367 extern bool enable_vmware_backdoor;
368 
369 extern int pi_inject_timer;
370 
371 extern bool report_ignored_msrs;
372 
373 extern bool eager_page_split;
374 
375 static inline void kvm_pr_unimpl_wrmsr(struct kvm_vcpu *vcpu, u32 msr, u64 data)
376 {
377 	if (report_ignored_msrs)
378 		vcpu_unimpl(vcpu, "Unhandled WRMSR(0x%x) = 0x%llx\n", msr, data);
379 }
380 
381 static inline void kvm_pr_unimpl_rdmsr(struct kvm_vcpu *vcpu, u32 msr)
382 {
383 	if (report_ignored_msrs)
384 		vcpu_unimpl(vcpu, "Unhandled RDMSR(0x%x)\n", msr);
385 }
386 
387 static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec)
388 {
389 	return pvclock_scale_delta(nsec, vcpu->arch.virtual_tsc_mult,
390 				   vcpu->arch.virtual_tsc_shift);
391 }
392 
393 /* Same "calling convention" as do_div:
394  * - divide (n << 32) by base
395  * - put result in n
396  * - return remainder
397  */
398 #define do_shl32_div32(n, base)					\
399 	({							\
400 	    u32 __quot, __rem;					\
401 	    asm("divl %2" : "=a" (__quot), "=d" (__rem)		\
402 			: "rm" (base), "0" (0), "1" ((u32) n));	\
403 	    n = __quot;						\
404 	    __rem;						\
405 	 })
406 
407 static inline bool kvm_mwait_in_guest(struct kvm *kvm)
408 {
409 	return kvm->arch.mwait_in_guest;
410 }
411 
412 static inline bool kvm_hlt_in_guest(struct kvm *kvm)
413 {
414 	return kvm->arch.hlt_in_guest;
415 }
416 
417 static inline bool kvm_pause_in_guest(struct kvm *kvm)
418 {
419 	return kvm->arch.pause_in_guest;
420 }
421 
422 static inline bool kvm_cstate_in_guest(struct kvm *kvm)
423 {
424 	return kvm->arch.cstate_in_guest;
425 }
426 
427 static inline bool kvm_notify_vmexit_enabled(struct kvm *kvm)
428 {
429 	return kvm->arch.notify_vmexit_flags & KVM_X86_NOTIFY_VMEXIT_ENABLED;
430 }
431 
432 enum kvm_intr_type {
433 	/* Values are arbitrary, but must be non-zero. */
434 	KVM_HANDLING_IRQ = 1,
435 	KVM_HANDLING_NMI,
436 };
437 
438 static __always_inline void kvm_before_interrupt(struct kvm_vcpu *vcpu,
439 						 enum kvm_intr_type intr)
440 {
441 	WRITE_ONCE(vcpu->arch.handling_intr_from_guest, (u8)intr);
442 }
443 
444 static __always_inline void kvm_after_interrupt(struct kvm_vcpu *vcpu)
445 {
446 	WRITE_ONCE(vcpu->arch.handling_intr_from_guest, 0);
447 }
448 
449 static inline bool kvm_handling_nmi_from_guest(struct kvm_vcpu *vcpu)
450 {
451 	return vcpu->arch.handling_intr_from_guest == KVM_HANDLING_NMI;
452 }
453 
454 static inline bool kvm_pat_valid(u64 data)
455 {
456 	if (data & 0xF8F8F8F8F8F8F8F8ull)
457 		return false;
458 	/* 0, 1, 4, 5, 6, 7 are valid values.  */
459 	return (data | ((data & 0x0202020202020202ull) << 1)) == data;
460 }
461 
462 static inline bool kvm_dr7_valid(u64 data)
463 {
464 	/* Bits [63:32] are reserved */
465 	return !(data >> 32);
466 }
467 static inline bool kvm_dr6_valid(u64 data)
468 {
469 	/* Bits [63:32] are reserved */
470 	return !(data >> 32);
471 }
472 
473 /*
474  * Trigger machine check on the host. We assume all the MSRs are already set up
475  * by the CPU and that we still run on the same CPU as the MCE occurred on.
476  * We pass a fake environment to the machine check handler because we want
477  * the guest to be always treated like user space, no matter what context
478  * it used internally.
479  */
480 static inline void kvm_machine_check(void)
481 {
482 #if defined(CONFIG_X86_MCE)
483 	struct pt_regs regs = {
484 		.cs = 3, /* Fake ring 3 no matter what the guest ran on */
485 		.flags = X86_EFLAGS_IF,
486 	};
487 
488 	do_machine_check(&regs);
489 #endif
490 }
491 
492 void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu);
493 void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu);
494 int kvm_spec_ctrl_test_value(u64 value);
495 bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
496 int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,
497 			      struct x86_exception *e);
498 int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva);
499 bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type);
500 
501 /*
502  * Internal error codes that are used to indicate that MSR emulation encountered
503  * an error that should result in #GP in the guest, unless userspace
504  * handles it.
505  */
506 #define  KVM_MSR_RET_INVALID	2	/* in-kernel MSR emulation #GP condition */
507 #define  KVM_MSR_RET_FILTERED	3	/* #GP due to userspace MSR filter */
508 
509 #define __cr4_reserved_bits(__cpu_has, __c)             \
510 ({                                                      \
511 	u64 __reserved_bits = CR4_RESERVED_BITS;        \
512                                                         \
513 	if (!__cpu_has(__c, X86_FEATURE_XSAVE))         \
514 		__reserved_bits |= X86_CR4_OSXSAVE;     \
515 	if (!__cpu_has(__c, X86_FEATURE_SMEP))          \
516 		__reserved_bits |= X86_CR4_SMEP;        \
517 	if (!__cpu_has(__c, X86_FEATURE_SMAP))          \
518 		__reserved_bits |= X86_CR4_SMAP;        \
519 	if (!__cpu_has(__c, X86_FEATURE_FSGSBASE))      \
520 		__reserved_bits |= X86_CR4_FSGSBASE;    \
521 	if (!__cpu_has(__c, X86_FEATURE_PKU))           \
522 		__reserved_bits |= X86_CR4_PKE;         \
523 	if (!__cpu_has(__c, X86_FEATURE_LA57))          \
524 		__reserved_bits |= X86_CR4_LA57;        \
525 	if (!__cpu_has(__c, X86_FEATURE_UMIP))          \
526 		__reserved_bits |= X86_CR4_UMIP;        \
527 	if (!__cpu_has(__c, X86_FEATURE_VMX))           \
528 		__reserved_bits |= X86_CR4_VMXE;        \
529 	if (!__cpu_has(__c, X86_FEATURE_PCID))          \
530 		__reserved_bits |= X86_CR4_PCIDE;       \
531 	__reserved_bits;                                \
532 })
533 
534 int kvm_sev_es_mmio_write(struct kvm_vcpu *vcpu, gpa_t src, unsigned int bytes,
535 			  void *dst);
536 int kvm_sev_es_mmio_read(struct kvm_vcpu *vcpu, gpa_t src, unsigned int bytes,
537 			 void *dst);
538 int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
539 			 unsigned int port, void *data,  unsigned int count,
540 			 int in);
541 
542 #endif
543