1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2020 - Google Inc
4 * Author: Andrew Scull <ascull@google.com>
5 */
6
7#include <hyp/adjust_pc.h>
8
9#include <asm/pgtable-types.h>
10#include <asm/kvm_asm.h>
11#include <asm/kvm_emulate.h>
12#include <asm/kvm_host.h>
13#include <asm/kvm_hyp.h>
14#include <asm/kvm_mmu.h>
15
16#include <nvhe/ffa.h>
17#include <nvhe/mem_protect.h>
18#include <nvhe/mm.h>
19#include <nvhe/pkvm.h>
20#include <nvhe/trap_handler.h>
21
22DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
23
24void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt);
25
26static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
27{
28	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
29
30	hyp_vcpu->vcpu.arch.ctxt	= host_vcpu->arch.ctxt;
31
32	hyp_vcpu->vcpu.arch.sve_state	= kern_hyp_va(host_vcpu->arch.sve_state);
33	hyp_vcpu->vcpu.arch.sve_max_vl	= host_vcpu->arch.sve_max_vl;
34
35	hyp_vcpu->vcpu.arch.hw_mmu	= host_vcpu->arch.hw_mmu;
36
37	hyp_vcpu->vcpu.arch.hcr_el2	= host_vcpu->arch.hcr_el2;
38	hyp_vcpu->vcpu.arch.mdcr_el2	= host_vcpu->arch.mdcr_el2;
39	hyp_vcpu->vcpu.arch.cptr_el2	= host_vcpu->arch.cptr_el2;
40
41	hyp_vcpu->vcpu.arch.iflags	= host_vcpu->arch.iflags;
42	hyp_vcpu->vcpu.arch.fp_state	= host_vcpu->arch.fp_state;
43
44	hyp_vcpu->vcpu.arch.debug_ptr	= kern_hyp_va(host_vcpu->arch.debug_ptr);
45	hyp_vcpu->vcpu.arch.host_fpsimd_state = host_vcpu->arch.host_fpsimd_state;
46
47	hyp_vcpu->vcpu.arch.vsesr_el2	= host_vcpu->arch.vsesr_el2;
48
49	hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3;
50}
51
52static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
53{
54	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
55	struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3;
56	struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3;
57	unsigned int i;
58
59	host_vcpu->arch.ctxt		= hyp_vcpu->vcpu.arch.ctxt;
60
61	host_vcpu->arch.hcr_el2		= hyp_vcpu->vcpu.arch.hcr_el2;
62	host_vcpu->arch.cptr_el2	= hyp_vcpu->vcpu.arch.cptr_el2;
63
64	host_vcpu->arch.fault		= hyp_vcpu->vcpu.arch.fault;
65
66	host_vcpu->arch.iflags		= hyp_vcpu->vcpu.arch.iflags;
67	host_vcpu->arch.fp_state	= hyp_vcpu->vcpu.arch.fp_state;
68
69	host_cpu_if->vgic_hcr		= hyp_cpu_if->vgic_hcr;
70	for (i = 0; i < hyp_cpu_if->used_lrs; ++i)
71		host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i];
72}
73
74static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
75{
76	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1);
77	int ret;
78
79	host_vcpu = kern_hyp_va(host_vcpu);
80
81	if (unlikely(is_protected_kvm_enabled())) {
82		struct pkvm_hyp_vcpu *hyp_vcpu;
83		struct kvm *host_kvm;
84
85		host_kvm = kern_hyp_va(host_vcpu->kvm);
86		hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle,
87					      host_vcpu->vcpu_idx);
88		if (!hyp_vcpu) {
89			ret = -EINVAL;
90			goto out;
91		}
92
93		flush_hyp_vcpu(hyp_vcpu);
94
95		ret = __kvm_vcpu_run(&hyp_vcpu->vcpu);
96
97		sync_hyp_vcpu(hyp_vcpu);
98		pkvm_put_hyp_vcpu(hyp_vcpu);
99	} else {
100		/* The host is fully trusted, run its vCPU directly. */
101		ret = __kvm_vcpu_run(host_vcpu);
102	}
103
104out:
105	cpu_reg(host_ctxt, 1) =  ret;
106}
107
108static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt)
109{
110	DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
111
112	__kvm_adjust_pc(kern_hyp_va(vcpu));
113}
114
115static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt)
116{
117	__kvm_flush_vm_context();
118}
119
120static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt)
121{
122	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
123	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
124	DECLARE_REG(int, level, host_ctxt, 3);
125
126	__kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level);
127}
128
129static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt)
130{
131	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
132	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
133	DECLARE_REG(int, level, host_ctxt, 3);
134
135	__kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level);
136}
137
138static void
139handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt)
140{
141	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
142	DECLARE_REG(phys_addr_t, start, host_ctxt, 2);
143	DECLARE_REG(unsigned long, pages, host_ctxt, 3);
144
145	__kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages);
146}
147
148static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
149{
150	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
151
152	__kvm_tlb_flush_vmid(kern_hyp_va(mmu));
153}
154
155static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt)
156{
157	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
158
159	__kvm_flush_cpu_context(kern_hyp_va(mmu));
160}
161
162static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
163{
164	__kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1));
165}
166
167static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
168{
169	u64 tmp;
170
171	tmp = read_sysreg_el2(SYS_SCTLR);
172	tmp |= SCTLR_ELx_DSSBS;
173	write_sysreg_el2(tmp, SYS_SCTLR);
174}
175
176static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
177{
178	cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
179}
180
181static void handle___vgic_v3_read_vmcr(struct kvm_cpu_context *host_ctxt)
182{
183	cpu_reg(host_ctxt, 1) = __vgic_v3_read_vmcr();
184}
185
186static void handle___vgic_v3_write_vmcr(struct kvm_cpu_context *host_ctxt)
187{
188	__vgic_v3_write_vmcr(cpu_reg(host_ctxt, 1));
189}
190
191static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
192{
193	__vgic_v3_init_lrs();
194}
195
196static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt)
197{
198	cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2();
199}
200
201static void handle___vgic_v3_save_aprs(struct kvm_cpu_context *host_ctxt)
202{
203	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
204
205	__vgic_v3_save_aprs(kern_hyp_va(cpu_if));
206}
207
208static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt)
209{
210	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
211
212	__vgic_v3_restore_aprs(kern_hyp_va(cpu_if));
213}
214
215static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
216{
217	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
218	DECLARE_REG(unsigned long, size, host_ctxt, 2);
219	DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
220	DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
221	DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
222
223	/*
224	 * __pkvm_init() will return only if an error occurred, otherwise it
225	 * will tail-call in __pkvm_init_finalise() which will have to deal
226	 * with the host context directly.
227	 */
228	cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
229					    hyp_va_bits);
230}
231
232static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
233{
234	DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1);
235
236	cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot);
237}
238
239static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt)
240{
241	DECLARE_REG(u64, pfn, host_ctxt, 1);
242
243	cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn);
244}
245
246static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt)
247{
248	DECLARE_REG(u64, pfn, host_ctxt, 1);
249
250	cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn);
251}
252
253static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt)
254{
255	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
256	DECLARE_REG(size_t, size, host_ctxt, 2);
257	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
258
259	/*
260	 * __pkvm_create_private_mapping() populates a pointer with the
261	 * hypervisor start address of the allocation.
262	 *
263	 * However, handle___pkvm_create_private_mapping() hypercall crosses the
264	 * EL1/EL2 boundary so the pointer would not be valid in this context.
265	 *
266	 * Instead pass the allocation address as the return value (or return
267	 * ERR_PTR() on failure).
268	 */
269	unsigned long haddr;
270	int err = __pkvm_create_private_mapping(phys, size, prot, &haddr);
271
272	if (err)
273		haddr = (unsigned long)ERR_PTR(err);
274
275	cpu_reg(host_ctxt, 1) = haddr;
276}
277
278static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
279{
280	cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
281}
282
283static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt)
284{
285	DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
286
287	__pkvm_vcpu_init_traps(kern_hyp_va(vcpu));
288}
289
290static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt)
291{
292	DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
293	DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2);
294	DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3);
295
296	host_kvm = kern_hyp_va(host_kvm);
297	cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva);
298}
299
300static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt)
301{
302	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
303	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2);
304	DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3);
305
306	host_vcpu = kern_hyp_va(host_vcpu);
307	cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva);
308}
309
310static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt)
311{
312	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
313
314	cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle);
315}
316
317typedef void (*hcall_t)(struct kvm_cpu_context *);
318
319#define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
320
321static const hcall_t host_hcall[] = {
322	/* ___kvm_hyp_init */
323	HANDLE_FUNC(__kvm_get_mdcr_el2),
324	HANDLE_FUNC(__pkvm_init),
325	HANDLE_FUNC(__pkvm_create_private_mapping),
326	HANDLE_FUNC(__pkvm_cpu_set_vector),
327	HANDLE_FUNC(__kvm_enable_ssbs),
328	HANDLE_FUNC(__vgic_v3_init_lrs),
329	HANDLE_FUNC(__vgic_v3_get_gic_config),
330	HANDLE_FUNC(__pkvm_prot_finalize),
331
332	HANDLE_FUNC(__pkvm_host_share_hyp),
333	HANDLE_FUNC(__pkvm_host_unshare_hyp),
334	HANDLE_FUNC(__kvm_adjust_pc),
335	HANDLE_FUNC(__kvm_vcpu_run),
336	HANDLE_FUNC(__kvm_flush_vm_context),
337	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
338	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh),
339	HANDLE_FUNC(__kvm_tlb_flush_vmid),
340	HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
341	HANDLE_FUNC(__kvm_flush_cpu_context),
342	HANDLE_FUNC(__kvm_timer_set_cntvoff),
343	HANDLE_FUNC(__vgic_v3_read_vmcr),
344	HANDLE_FUNC(__vgic_v3_write_vmcr),
345	HANDLE_FUNC(__vgic_v3_save_aprs),
346	HANDLE_FUNC(__vgic_v3_restore_aprs),
347	HANDLE_FUNC(__pkvm_vcpu_init_traps),
348	HANDLE_FUNC(__pkvm_init_vm),
349	HANDLE_FUNC(__pkvm_init_vcpu),
350	HANDLE_FUNC(__pkvm_teardown_vm),
351};
352
353static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
354{
355	DECLARE_REG(unsigned long, id, host_ctxt, 0);
356	unsigned long hcall_min = 0;
357	hcall_t hfn;
358
359	/*
360	 * If pKVM has been initialised then reject any calls to the
361	 * early "privileged" hypercalls. Note that we cannot reject
362	 * calls to __pkvm_prot_finalize for two reasons: (1) The static
363	 * key used to determine initialisation must be toggled prior to
364	 * finalisation and (2) finalisation is performed on a per-CPU
365	 * basis. This is all fine, however, since __pkvm_prot_finalize
366	 * returns -EPERM after the first call for a given CPU.
367	 */
368	if (static_branch_unlikely(&kvm_protected_mode_initialized))
369		hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize;
370
371	id &= ~ARM_SMCCC_CALL_HINTS;
372	id -= KVM_HOST_SMCCC_ID(0);
373
374	if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall)))
375		goto inval;
376
377	hfn = host_hcall[id];
378	if (unlikely(!hfn))
379		goto inval;
380
381	cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
382	hfn(host_ctxt);
383
384	return;
385inval:
386	cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;
387}
388
389static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt)
390{
391	__kvm_hyp_host_forward_smc(host_ctxt);
392}
393
394static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
395{
396	DECLARE_REG(u64, func_id, host_ctxt, 0);
397	bool handled;
398
399	func_id &= ~ARM_SMCCC_CALL_HINTS;
400
401	handled = kvm_host_psci_handler(host_ctxt, func_id);
402	if (!handled)
403		handled = kvm_host_ffa_handler(host_ctxt, func_id);
404	if (!handled)
405		default_host_smc_handler(host_ctxt);
406
407	/* SMC was trapped, move ELR past the current PC. */
408	kvm_skip_host_instr();
409}
410
411void handle_trap(struct kvm_cpu_context *host_ctxt)
412{
413	u64 esr = read_sysreg_el2(SYS_ESR);
414
415	switch (ESR_ELx_EC(esr)) {
416	case ESR_ELx_EC_HVC64:
417		handle_host_hcall(host_ctxt);
418		break;
419	case ESR_ELx_EC_SMC64:
420		handle_host_smc(host_ctxt);
421		break;
422	case ESR_ELx_EC_SVE:
423		if (has_hvhe())
424			sysreg_clear_set(cpacr_el1, 0, (CPACR_EL1_ZEN_EL1EN |
425							CPACR_EL1_ZEN_EL0EN));
426		else
427			sysreg_clear_set(cptr_el2, CPTR_EL2_TZ, 0);
428		isb();
429		sve_cond_update_zcr_vq(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2);
430		break;
431	case ESR_ELx_EC_IABT_LOW:
432	case ESR_ELx_EC_DABT_LOW:
433		handle_host_mem_abort(host_ctxt);
434		break;
435	default:
436		BUG();
437	}
438}
439