1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Hyper-V Isolation VM interface with paravisor and hypervisor
4 *
5 * Author:
6 * Tianyu Lan <Tianyu.Lan@microsoft.com>
7 */
8
9#include <linux/bitfield.h>
10#include <linux/hyperv.h>
11#include <linux/types.h>
12#include <linux/slab.h>
13#include <asm/svm.h>
14#include <asm/sev.h>
15#include <asm/io.h>
16#include <asm/coco.h>
17#include <asm/mem_encrypt.h>
18#include <asm/set_memory.h>
19#include <asm/mshyperv.h>
20#include <asm/hypervisor.h>
21#include <asm/mtrr.h>
22#include <asm/io_apic.h>
23#include <asm/realmode.h>
24#include <asm/e820/api.h>
25#include <asm/desc.h>
26#include <uapi/asm/vmx.h>
27
28#ifdef CONFIG_AMD_MEM_ENCRYPT
29
30#define GHCB_USAGE_HYPERV_CALL 1
31
32union hv_ghcb {
33 struct ghcb ghcb;
34 struct {
35 u64 hypercalldata[509];
36 u64 outputgpa;
37 union {
38 union {
39 struct {
40 u32 callcode : 16;
41 u32 isfast : 1;
42 u32 reserved1 : 14;
43 u32 isnested : 1;
44 u32 countofelements : 12;
45 u32 reserved2 : 4;
46 u32 repstartindex : 12;
47 u32 reserved3 : 4;
48 };
49 u64 asuint64;
50 } hypercallinput;
51 union {
52 struct {
53 u16 callstatus;
54 u16 reserved1;
55 u32 elementsprocessed : 12;
56 u32 reserved2 : 20;
57 };
58 u64 asunit64;
59 } hypercalloutput;
60 };
61 u64 reserved2;
62 } hypercall;
63} __packed __aligned(HV_HYP_PAGE_SIZE);
64
65/* Only used in an SNP VM with the paravisor */
66static u16 hv_ghcb_version __ro_after_init;
67
68/* Functions only used in an SNP VM with the paravisor go here. */
69u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size)
70{
71 union hv_ghcb *hv_ghcb;
72 void **ghcb_base;
73 unsigned long flags;
74 u64 status;
75
76 if (!hv_ghcb_pg)
77 return -EFAULT;
78
79 WARN_ON(in_nmi());
80
81 local_irq_save(flags);
82 ghcb_base = (void **)this_cpu_ptr(hv_ghcb_pg);
83 hv_ghcb = (union hv_ghcb *)*ghcb_base;
84 if (!hv_ghcb) {
85 local_irq_restore(flags);
86 return -EFAULT;
87 }
88
89 hv_ghcb->ghcb.protocol_version = GHCB_PROTOCOL_MAX;
90 hv_ghcb->ghcb.ghcb_usage = GHCB_USAGE_HYPERV_CALL;
91
92 hv_ghcb->hypercall.outputgpa = (u64)output;
93 hv_ghcb->hypercall.hypercallinput.asuint64 = 0;
94 hv_ghcb->hypercall.hypercallinput.callcode = control;
95
96 if (input_size)
97 memcpy(hv_ghcb->hypercall.hypercalldata, input, input_size);
98
99 VMGEXIT();
100
101 hv_ghcb->ghcb.ghcb_usage = 0xffffffff;
102 memset(hv_ghcb->ghcb.save.valid_bitmap, 0,
103 sizeof(hv_ghcb->ghcb.save.valid_bitmap));
104
105 status = hv_ghcb->hypercall.hypercalloutput.callstatus;
106
107 local_irq_restore(flags);
108
109 return status;
110}
111
112static inline u64 rd_ghcb_msr(void)
113{
114 return __rdmsr(MSR_AMD64_SEV_ES_GHCB);
115}
116
117static inline void wr_ghcb_msr(u64 val)
118{
119 native_wrmsrl(MSR_AMD64_SEV_ES_GHCB, val);
120}
121
122static enum es_result hv_ghcb_hv_call(struct ghcb *ghcb, u64 exit_code,
123 u64 exit_info_1, u64 exit_info_2)
124{
125 /* Fill in protocol and format specifiers */
126 ghcb->protocol_version = hv_ghcb_version;
127 ghcb->ghcb_usage = GHCB_DEFAULT_USAGE;
128
129 ghcb_set_sw_exit_code(ghcb, value: exit_code);
130 ghcb_set_sw_exit_info_1(ghcb, value: exit_info_1);
131 ghcb_set_sw_exit_info_2(ghcb, value: exit_info_2);
132
133 VMGEXIT();
134
135 if (ghcb->save.sw_exit_info_1 & GENMASK_ULL(31, 0))
136 return ES_VMM_ERROR;
137 else
138 return ES_OK;
139}
140
141void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason)
142{
143 u64 val = GHCB_MSR_TERM_REQ;
144
145 /* Tell the hypervisor what went wrong. */
146 val |= GHCB_SEV_TERM_REASON(set, reason);
147
148 /* Request Guest Termination from Hypervisor */
149 wr_ghcb_msr(val);
150 VMGEXIT();
151
152 while (true)
153 asm volatile("hlt\n" : : : "memory");
154}
155
156bool hv_ghcb_negotiate_protocol(void)
157{
158 u64 ghcb_gpa;
159 u64 val;
160
161 /* Save ghcb page gpa. */
162 ghcb_gpa = rd_ghcb_msr();
163
164 /* Do the GHCB protocol version negotiation */
165 wr_ghcb_msr(GHCB_MSR_SEV_INFO_REQ);
166 VMGEXIT();
167 val = rd_ghcb_msr();
168
169 if (GHCB_MSR_INFO(val) != GHCB_MSR_SEV_INFO_RESP)
170 return false;
171
172 if (GHCB_MSR_PROTO_MAX(val) < GHCB_PROTOCOL_MIN ||
173 GHCB_MSR_PROTO_MIN(val) > GHCB_PROTOCOL_MAX)
174 return false;
175
176 hv_ghcb_version = min_t(size_t, GHCB_MSR_PROTO_MAX(val),
177 GHCB_PROTOCOL_MAX);
178
179 /* Write ghcb page back after negotiating protocol. */
180 wr_ghcb_msr(val: ghcb_gpa);
181 VMGEXIT();
182
183 return true;
184}
185
186static void hv_ghcb_msr_write(u64 msr, u64 value)
187{
188 union hv_ghcb *hv_ghcb;
189 void **ghcb_base;
190 unsigned long flags;
191
192 if (!hv_ghcb_pg)
193 return;
194
195 WARN_ON(in_nmi());
196
197 local_irq_save(flags);
198 ghcb_base = (void **)this_cpu_ptr(hv_ghcb_pg);
199 hv_ghcb = (union hv_ghcb *)*ghcb_base;
200 if (!hv_ghcb) {
201 local_irq_restore(flags);
202 return;
203 }
204
205 ghcb_set_rcx(ghcb: &hv_ghcb->ghcb, value: msr);
206 ghcb_set_rax(ghcb: &hv_ghcb->ghcb, lower_32_bits(value));
207 ghcb_set_rdx(ghcb: &hv_ghcb->ghcb, upper_32_bits(value));
208
209 if (hv_ghcb_hv_call(ghcb: &hv_ghcb->ghcb, SVM_EXIT_MSR, exit_info_1: 1, exit_info_2: 0))
210 pr_warn("Fail to write msr via ghcb %llx.\n", msr);
211
212 local_irq_restore(flags);
213}
214
215static void hv_ghcb_msr_read(u64 msr, u64 *value)
216{
217 union hv_ghcb *hv_ghcb;
218 void **ghcb_base;
219 unsigned long flags;
220
221 /* Check size of union hv_ghcb here. */
222 BUILD_BUG_ON(sizeof(union hv_ghcb) != HV_HYP_PAGE_SIZE);
223
224 if (!hv_ghcb_pg)
225 return;
226
227 WARN_ON(in_nmi());
228
229 local_irq_save(flags);
230 ghcb_base = (void **)this_cpu_ptr(hv_ghcb_pg);
231 hv_ghcb = (union hv_ghcb *)*ghcb_base;
232 if (!hv_ghcb) {
233 local_irq_restore(flags);
234 return;
235 }
236
237 ghcb_set_rcx(ghcb: &hv_ghcb->ghcb, value: msr);
238 if (hv_ghcb_hv_call(ghcb: &hv_ghcb->ghcb, SVM_EXIT_MSR, exit_info_1: 0, exit_info_2: 0))
239 pr_warn("Fail to read msr via ghcb %llx.\n", msr);
240 else
241 *value = (u64)lower_32_bits(hv_ghcb->ghcb.save.rax)
242 | ((u64)lower_32_bits(hv_ghcb->ghcb.save.rdx) << 32);
243 local_irq_restore(flags);
244}
245
246/* Only used in a fully enlightened SNP VM, i.e. without the paravisor */
247static u8 ap_start_input_arg[PAGE_SIZE] __bss_decrypted __aligned(PAGE_SIZE);
248static u8 ap_start_stack[PAGE_SIZE] __aligned(PAGE_SIZE);
249static DEFINE_PER_CPU(struct sev_es_save_area *, hv_sev_vmsa);
250
251/* Functions only used in an SNP VM without the paravisor go here. */
252
253#define hv_populate_vmcb_seg(seg, gdtr_base) \
254do { \
255 if (seg.selector) { \
256 seg.base = 0; \
257 seg.limit = HV_AP_SEGMENT_LIMIT; \
258 seg.attrib = *(u16 *)(gdtr_base + seg.selector + 5); \
259 seg.attrib = (seg.attrib & 0xFF) | ((seg.attrib >> 4) & 0xF00); \
260 } \
261} while (0) \
262
263static int snp_set_vmsa(void *va, bool vmsa)
264{
265 u64 attrs;
266
267 /*
268 * Running at VMPL0 allows the kernel to change the VMSA bit for a page
269 * using the RMPADJUST instruction. However, for the instruction to
270 * succeed it must target the permissions of a lesser privileged
271 * (higher numbered) VMPL level, so use VMPL1 (refer to the RMPADJUST
272 * instruction in the AMD64 APM Volume 3).
273 */
274 attrs = 1;
275 if (vmsa)
276 attrs |= RMPADJUST_VMSA_PAGE_BIT;
277
278 return rmpadjust(vaddr: (unsigned long)va, RMP_PG_SIZE_4K, attrs);
279}
280
281static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa)
282{
283 int err;
284
285 err = snp_set_vmsa(va: vmsa, vmsa: false);
286 if (err)
287 pr_err("clear VMSA page failed (%u), leaking page\n", err);
288 else
289 free_page((unsigned long)vmsa);
290}
291
292int hv_snp_boot_ap(u32 cpu, unsigned long start_ip)
293{
294 struct sev_es_save_area *vmsa = (struct sev_es_save_area *)
295 __get_free_page(GFP_KERNEL | __GFP_ZERO);
296 struct sev_es_save_area *cur_vmsa;
297 struct desc_ptr gdtr;
298 u64 ret, retry = 5;
299 struct hv_enable_vp_vtl *start_vp_input;
300 unsigned long flags;
301
302 if (!vmsa)
303 return -ENOMEM;
304
305 native_store_gdt(dtr: &gdtr);
306
307 vmsa->gdtr.base = gdtr.address;
308 vmsa->gdtr.limit = gdtr.size;
309
310 asm volatile("movl %%es, %%eax;" : "=a" (vmsa->es.selector));
311 hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base);
312
313 asm volatile("movl %%cs, %%eax;" : "=a" (vmsa->cs.selector));
314 hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base);
315
316 asm volatile("movl %%ss, %%eax;" : "=a" (vmsa->ss.selector));
317 hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base);
318
319 asm volatile("movl %%ds, %%eax;" : "=a" (vmsa->ds.selector));
320 hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base);
321
322 vmsa->efer = native_read_msr(MSR_EFER);
323
324 asm volatile("movq %%cr4, %%rax;" : "=a" (vmsa->cr4));
325 asm volatile("movq %%cr3, %%rax;" : "=a" (vmsa->cr3));
326 asm volatile("movq %%cr0, %%rax;" : "=a" (vmsa->cr0));
327
328 vmsa->xcr0 = 1;
329 vmsa->g_pat = HV_AP_INIT_GPAT_DEFAULT;
330 vmsa->rip = (u64)secondary_startup_64_no_verify;
331 vmsa->rsp = (u64)&ap_start_stack[PAGE_SIZE];
332
333 /*
334 * Set the SNP-specific fields for this VMSA:
335 * VMPL level
336 * SEV_FEATURES (matches the SEV STATUS MSR right shifted 2 bits)
337 */
338 vmsa->vmpl = 0;
339 vmsa->sev_features = sev_status >> 2;
340
341 ret = snp_set_vmsa(va: vmsa, vmsa: true);
342 if (!ret) {
343 pr_err("RMPADJUST(%llx) failed: %llx\n", (u64)vmsa, ret);
344 free_page((u64)vmsa);
345 return ret;
346 }
347
348 local_irq_save(flags);
349 start_vp_input = (struct hv_enable_vp_vtl *)ap_start_input_arg;
350 memset(start_vp_input, 0, sizeof(*start_vp_input));
351 start_vp_input->partition_id = -1;
352 start_vp_input->vp_index = cpu;
353 start_vp_input->target_vtl.target_vtl = ms_hyperv.vtl;
354 *(u64 *)&start_vp_input->vp_context = __pa(vmsa) | 1;
355
356 do {
357 ret = hv_do_hypercall(HVCALL_START_VP,
358 inputaddr: start_vp_input, NULL);
359 } while (hv_result(status: ret) == HV_STATUS_TIME_OUT && retry--);
360
361 local_irq_restore(flags);
362
363 if (!hv_result_success(status: ret)) {
364 pr_err("HvCallStartVirtualProcessor failed: %llx\n", ret);
365 snp_cleanup_vmsa(vmsa);
366 vmsa = NULL;
367 }
368
369 cur_vmsa = per_cpu(hv_sev_vmsa, cpu);
370 /* Free up any previous VMSA page */
371 if (cur_vmsa)
372 snp_cleanup_vmsa(vmsa: cur_vmsa);
373
374 /* Record the current VMSA page */
375 per_cpu(hv_sev_vmsa, cpu) = vmsa;
376
377 return ret;
378}
379
380#else
381static inline void hv_ghcb_msr_write(u64 msr, u64 value) {}
382static inline void hv_ghcb_msr_read(u64 msr, u64 *value) {}
383#endif /* CONFIG_AMD_MEM_ENCRYPT */
384
385#ifdef CONFIG_INTEL_TDX_GUEST
386static void hv_tdx_msr_write(u64 msr, u64 val)
387{
388 struct tdx_module_args args = {
389 .r10 = TDX_HYPERCALL_STANDARD,
390 .r11 = EXIT_REASON_MSR_WRITE,
391 .r12 = msr,
392 .r13 = val,
393 };
394
395 u64 ret = __tdx_hypercall(args: &args);
396
397 WARN_ONCE(ret, "Failed to emulate MSR write: %lld\n", ret);
398}
399
400static void hv_tdx_msr_read(u64 msr, u64 *val)
401{
402 struct tdx_module_args args = {
403 .r10 = TDX_HYPERCALL_STANDARD,
404 .r11 = EXIT_REASON_MSR_READ,
405 .r12 = msr,
406 };
407
408 u64 ret = __tdx_hypercall(args: &args);
409
410 if (WARN_ONCE(ret, "Failed to emulate MSR read: %lld\n", ret))
411 *val = 0;
412 else
413 *val = args.r11;
414}
415
416u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2)
417{
418 struct tdx_module_args args = { };
419
420 args.r10 = control;
421 args.rdx = param1;
422 args.r8 = param2;
423
424 (void)__tdx_hypercall(args: &args);
425
426 return args.r11;
427}
428
429#else
430static inline void hv_tdx_msr_write(u64 msr, u64 value) {}
431static inline void hv_tdx_msr_read(u64 msr, u64 *value) {}
432#endif /* CONFIG_INTEL_TDX_GUEST */
433
434#if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST)
435void hv_ivm_msr_write(u64 msr, u64 value)
436{
437 if (!ms_hyperv.paravisor_present)
438 return;
439
440 if (hv_isolation_type_tdx())
441 hv_tdx_msr_write(msr, val: value);
442 else if (hv_isolation_type_snp())
443 hv_ghcb_msr_write(msr, value);
444}
445
446void hv_ivm_msr_read(u64 msr, u64 *value)
447{
448 if (!ms_hyperv.paravisor_present)
449 return;
450
451 if (hv_isolation_type_tdx())
452 hv_tdx_msr_read(msr, val: value);
453 else if (hv_isolation_type_snp())
454 hv_ghcb_msr_read(msr, value);
455}
456
457/*
458 * hv_mark_gpa_visibility - Set pages visible to host via hvcall.
459 *
460 * In Isolation VM, all guest memory is encrypted from host and guest
461 * needs to set memory visible to host via hvcall before sharing memory
462 * with host.
463 */
464static int hv_mark_gpa_visibility(u16 count, const u64 pfn[],
465 enum hv_mem_host_visibility visibility)
466{
467 struct hv_gpa_range_for_visibility *input;
468 u16 pages_processed;
469 u64 hv_status;
470 unsigned long flags;
471
472 /* no-op if partition isolation is not enabled */
473 if (!hv_is_isolation_supported())
474 return 0;
475
476 if (count > HV_MAX_MODIFY_GPA_REP_COUNT) {
477 pr_err("Hyper-V: GPA count:%d exceeds supported:%lu\n", count,
478 HV_MAX_MODIFY_GPA_REP_COUNT);
479 return -EINVAL;
480 }
481
482 local_irq_save(flags);
483 input = *this_cpu_ptr(hyperv_pcpu_input_arg);
484
485 if (unlikely(!input)) {
486 local_irq_restore(flags);
487 return -EINVAL;
488 }
489
490 input->partition_id = HV_PARTITION_ID_SELF;
491 input->host_visibility = visibility;
492 input->reserved0 = 0;
493 input->reserved1 = 0;
494 memcpy((void *)input->gpa_page_list, pfn, count * sizeof(*pfn));
495 hv_status = hv_do_rep_hypercall(
496 HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY, rep_count: count,
497 varhead_size: 0, input, output: &pages_processed);
498 local_irq_restore(flags);
499
500 if (hv_result_success(status: hv_status))
501 return 0;
502 else
503 return -EFAULT;
504}
505
506/*
507 * When transitioning memory between encrypted and decrypted, the caller
508 * of set_memory_encrypted() or set_memory_decrypted() is responsible for
509 * ensuring that the memory isn't in use and isn't referenced while the
510 * transition is in progress. The transition has multiple steps, and the
511 * memory is in an inconsistent state until all steps are complete. A
512 * reference while the state is inconsistent could result in an exception
513 * that can't be cleanly fixed up.
514 *
515 * But the Linux kernel load_unaligned_zeropad() mechanism could cause a
516 * stray reference that can't be prevented by the caller, so Linux has
517 * specific code to handle this case. But when the #VC and #VE exceptions
518 * routed to a paravisor, the specific code doesn't work. To avoid this
519 * problem, mark the pages as "not present" while the transition is in
520 * progress. If load_unaligned_zeropad() causes a stray reference, a normal
521 * page fault is generated instead of #VC or #VE, and the page-fault-based
522 * handlers for load_unaligned_zeropad() resolve the reference. When the
523 * transition is complete, hv_vtom_set_host_visibility() marks the pages
524 * as "present" again.
525 */
526static bool hv_vtom_clear_present(unsigned long kbuffer, int pagecount, bool enc)
527{
528 return !set_memory_np(addr: kbuffer, numpages: pagecount);
529}
530
531/*
532 * hv_vtom_set_host_visibility - Set specified memory visible to host.
533 *
534 * In Isolation VM, all guest memory is encrypted from host and guest
535 * needs to set memory visible to host via hvcall before sharing memory
536 * with host. This function works as wrap of hv_mark_gpa_visibility()
537 * with memory base and size.
538 */
539static bool hv_vtom_set_host_visibility(unsigned long kbuffer, int pagecount, bool enc)
540{
541 enum hv_mem_host_visibility visibility = enc ?
542 VMBUS_PAGE_NOT_VISIBLE : VMBUS_PAGE_VISIBLE_READ_WRITE;
543 u64 *pfn_array;
544 phys_addr_t paddr;
545 void *vaddr;
546 int ret = 0;
547 bool result = true;
548 int i, pfn;
549
550 pfn_array = kmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL);
551 if (!pfn_array) {
552 result = false;
553 goto err_set_memory_p;
554 }
555
556 for (i = 0, pfn = 0; i < pagecount; i++) {
557 /*
558 * Use slow_virt_to_phys() because the PRESENT bit has been
559 * temporarily cleared in the PTEs. slow_virt_to_phys() works
560 * without the PRESENT bit while virt_to_hvpfn() or similar
561 * does not.
562 */
563 vaddr = (void *)kbuffer + (i * HV_HYP_PAGE_SIZE);
564 paddr = slow_virt_to_phys(address: vaddr);
565 pfn_array[pfn] = paddr >> HV_HYP_PAGE_SHIFT;
566 pfn++;
567
568 if (pfn == HV_MAX_MODIFY_GPA_REP_COUNT || i == pagecount - 1) {
569 ret = hv_mark_gpa_visibility(count: pfn, pfn: pfn_array,
570 visibility);
571 if (ret) {
572 result = false;
573 goto err_free_pfn_array;
574 }
575 pfn = 0;
576 }
577 }
578
579err_free_pfn_array:
580 kfree(objp: pfn_array);
581
582err_set_memory_p:
583 /*
584 * Set the PTE PRESENT bits again to revert what hv_vtom_clear_present()
585 * did. Do this even if there is an error earlier in this function in
586 * order to avoid leaving the memory range in a "broken" state. Setting
587 * the PRESENT bits shouldn't fail, but return an error if it does.
588 */
589 if (set_memory_p(addr: kbuffer, numpages: pagecount))
590 result = false;
591
592 return result;
593}
594
595static bool hv_vtom_tlb_flush_required(bool private)
596{
597 /*
598 * Since hv_vtom_clear_present() marks the PTEs as "not present"
599 * and flushes the TLB, they can't be in the TLB. That makes the
600 * flush controlled by this function redundant, so return "false".
601 */
602 return false;
603}
604
605static bool hv_vtom_cache_flush_required(void)
606{
607 return false;
608}
609
610static bool hv_is_private_mmio(u64 addr)
611{
612 /*
613 * Hyper-V always provides a single IO-APIC in a guest VM.
614 * When a paravisor is used, it is emulated by the paravisor
615 * in the guest context and must be mapped private.
616 */
617 if (addr >= HV_IOAPIC_BASE_ADDRESS &&
618 addr < (HV_IOAPIC_BASE_ADDRESS + PAGE_SIZE))
619 return true;
620
621 /* Same with a vTPM */
622 if (addr >= VTPM_BASE_ADDRESS &&
623 addr < (VTPM_BASE_ADDRESS + PAGE_SIZE))
624 return true;
625
626 return false;
627}
628
629void __init hv_vtom_init(void)
630{
631 enum hv_isolation_type type = hv_get_isolation_type();
632
633 switch (type) {
634 case HV_ISOLATION_TYPE_VBS:
635 fallthrough;
636 /*
637 * By design, a VM using vTOM doesn't see the SEV setting,
638 * so SEV initialization is bypassed and sev_status isn't set.
639 * Set it here to indicate a vTOM VM.
640 *
641 * Note: if CONFIG_AMD_MEM_ENCRYPT is not set, sev_status is
642 * defined as 0ULL, to which we can't assigned a value.
643 */
644#ifdef CONFIG_AMD_MEM_ENCRYPT
645 case HV_ISOLATION_TYPE_SNP:
646 sev_status = MSR_AMD64_SNP_VTOM;
647 cc_vendor = CC_VENDOR_AMD;
648 break;
649#endif
650
651 case HV_ISOLATION_TYPE_TDX:
652 cc_vendor = CC_VENDOR_INTEL;
653 break;
654
655 default:
656 panic(fmt: "hv_vtom_init: unsupported isolation type %d\n", type);
657 }
658
659 cc_set_mask(mask: ms_hyperv.shared_gpa_boundary);
660 physical_mask &= ms_hyperv.shared_gpa_boundary - 1;
661
662 x86_platform.hyper.is_private_mmio = hv_is_private_mmio;
663 x86_platform.guest.enc_cache_flush_required = hv_vtom_cache_flush_required;
664 x86_platform.guest.enc_tlb_flush_required = hv_vtom_tlb_flush_required;
665 x86_platform.guest.enc_status_change_prepare = hv_vtom_clear_present;
666 x86_platform.guest.enc_status_change_finish = hv_vtom_set_host_visibility;
667
668 /* Set WB as the default cache mode. */
669 mtrr_overwrite_state(NULL, num_var: 0, MTRR_TYPE_WRBACK);
670}
671
672#endif /* defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST) */
673
674enum hv_isolation_type hv_get_isolation_type(void)
675{
676 if (!(ms_hyperv.priv_high & HV_ISOLATION))
677 return HV_ISOLATION_TYPE_NONE;
678 return FIELD_GET(HV_ISOLATION_TYPE, ms_hyperv.isolation_config_b);
679}
680EXPORT_SYMBOL_GPL(hv_get_isolation_type);
681
682/*
683 * hv_is_isolation_supported - Check system runs in the Hyper-V
684 * isolation VM.
685 */
686bool hv_is_isolation_supported(void)
687{
688 if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
689 return false;
690
691 if (!hypervisor_is_type(type: X86_HYPER_MS_HYPERV))
692 return false;
693
694 return hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE;
695}
696
697DEFINE_STATIC_KEY_FALSE(isolation_type_snp);
698
699/*
700 * hv_isolation_type_snp - Check if the system runs in an AMD SEV-SNP based
701 * isolation VM.
702 */
703bool hv_isolation_type_snp(void)
704{
705 return static_branch_unlikely(&isolation_type_snp);
706}
707
708DEFINE_STATIC_KEY_FALSE(isolation_type_tdx);
709/*
710 * hv_isolation_type_tdx - Check if the system runs in an Intel TDX based
711 * isolated VM.
712 */
713bool hv_isolation_type_tdx(void)
714{
715 return static_branch_unlikely(&isolation_type_tdx);
716}
717

source code of linux/arch/x86/hyperv/ivm.c