xref: /linux/arch/arm64/kvm/hyp/nvhe/hyp-main.c (revision adc4fb9c814b5d5cc6021022900fd5eb0b3c8165)
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 #include <hyp/switch.h>
9 
10 #include <asm/pgtable-types.h>
11 #include <asm/kvm_asm.h>
12 #include <asm/kvm_emulate.h>
13 #include <asm/kvm_host.h>
14 #include <asm/kvm_hyp.h>
15 #include <asm/kvm_mmu.h>
16 
17 #include <nvhe/ffa.h>
18 #include <nvhe/mem_protect.h>
19 #include <nvhe/mm.h>
20 #include <nvhe/pkvm.h>
21 #include <nvhe/trap_handler.h>
22 
23 DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
24 
25 void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt);
26 
__hyp_sve_save_guest(struct kvm_vcpu * vcpu)27 static void __hyp_sve_save_guest(struct kvm_vcpu *vcpu)
28 {
29 	__vcpu_sys_reg(vcpu, ZCR_EL1) = read_sysreg_el1(SYS_ZCR);
30 	/*
31 	 * On saving/restoring guest sve state, always use the maximum VL for
32 	 * the guest. The layout of the data when saving the sve state depends
33 	 * on the VL, so use a consistent (i.e., the maximum) guest VL.
34 	 */
35 	sve_cond_update_zcr_vq(vcpu_sve_max_vq(vcpu) - 1, SYS_ZCR_EL2);
36 	__sve_save_state(vcpu_sve_pffr(vcpu), &vcpu->arch.ctxt.fp_regs.fpsr, true);
37 	write_sysreg_s(sve_vq_from_vl(kvm_host_sve_max_vl) - 1, SYS_ZCR_EL2);
38 }
39 
__hyp_sve_restore_host(void)40 static void __hyp_sve_restore_host(void)
41 {
42 	struct cpu_sve_state *sve_state = *host_data_ptr(sve_state);
43 
44 	/*
45 	 * On saving/restoring host sve state, always use the maximum VL for
46 	 * the host. The layout of the data when saving the sve state depends
47 	 * on the VL, so use a consistent (i.e., the maximum) host VL.
48 	 *
49 	 * Note that this constrains the PE to the maximum shared VL
50 	 * that was discovered, if we wish to use larger VLs this will
51 	 * need to be revisited.
52 	 */
53 	write_sysreg_s(sve_vq_from_vl(kvm_host_sve_max_vl) - 1, SYS_ZCR_EL2);
54 	__sve_restore_state(sve_state->sve_regs + sve_ffr_offset(kvm_host_sve_max_vl),
55 			    &sve_state->fpsr,
56 			    true);
57 	write_sysreg_el1(sve_state->zcr_el1, SYS_ZCR);
58 }
59 
fpsimd_sve_flush(void)60 static void fpsimd_sve_flush(void)
61 {
62 	*host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED;
63 }
64 
fpsimd_sve_sync(struct kvm_vcpu * vcpu)65 static void fpsimd_sve_sync(struct kvm_vcpu *vcpu)
66 {
67 	bool has_fpmr;
68 
69 	if (!guest_owns_fp_regs())
70 		return;
71 
72 	cpacr_clear_set(0, CPACR_EL1_FPEN | CPACR_EL1_ZEN);
73 	isb();
74 
75 	if (vcpu_has_sve(vcpu))
76 		__hyp_sve_save_guest(vcpu);
77 	else
78 		__fpsimd_save_state(&vcpu->arch.ctxt.fp_regs);
79 
80 	has_fpmr = kvm_has_fpmr(kern_hyp_va(vcpu->kvm));
81 	if (has_fpmr)
82 		__vcpu_sys_reg(vcpu, FPMR) = read_sysreg_s(SYS_FPMR);
83 
84 	if (system_supports_sve())
85 		__hyp_sve_restore_host();
86 	else
87 		__fpsimd_restore_state(host_data_ptr(host_ctxt.fp_regs));
88 
89 	if (has_fpmr)
90 		write_sysreg_s(*host_data_ptr(fpmr), SYS_FPMR);
91 
92 	*host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED;
93 }
94 
flush_debug_state(struct pkvm_hyp_vcpu * hyp_vcpu)95 static void flush_debug_state(struct pkvm_hyp_vcpu *hyp_vcpu)
96 {
97 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
98 
99 	hyp_vcpu->vcpu.arch.debug_owner = host_vcpu->arch.debug_owner;
100 
101 	if (kvm_guest_owns_debug_regs(&hyp_vcpu->vcpu))
102 		hyp_vcpu->vcpu.arch.vcpu_debug_state = host_vcpu->arch.vcpu_debug_state;
103 	else if (kvm_host_owns_debug_regs(&hyp_vcpu->vcpu))
104 		hyp_vcpu->vcpu.arch.external_debug_state = host_vcpu->arch.external_debug_state;
105 }
106 
sync_debug_state(struct pkvm_hyp_vcpu * hyp_vcpu)107 static void sync_debug_state(struct pkvm_hyp_vcpu *hyp_vcpu)
108 {
109 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
110 
111 	if (kvm_guest_owns_debug_regs(&hyp_vcpu->vcpu))
112 		host_vcpu->arch.vcpu_debug_state = hyp_vcpu->vcpu.arch.vcpu_debug_state;
113 	else if (kvm_host_owns_debug_regs(&hyp_vcpu->vcpu))
114 		host_vcpu->arch.external_debug_state = hyp_vcpu->vcpu.arch.external_debug_state;
115 }
116 
flush_hyp_vcpu(struct pkvm_hyp_vcpu * hyp_vcpu)117 static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
118 {
119 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
120 
121 	fpsimd_sve_flush();
122 	flush_debug_state(hyp_vcpu);
123 
124 	hyp_vcpu->vcpu.arch.ctxt	= host_vcpu->arch.ctxt;
125 
126 	hyp_vcpu->vcpu.arch.sve_state	= kern_hyp_va(host_vcpu->arch.sve_state);
127 	/* Limit guest vector length to the maximum supported by the host.  */
128 	hyp_vcpu->vcpu.arch.sve_max_vl	= min(host_vcpu->arch.sve_max_vl, kvm_host_sve_max_vl);
129 
130 	hyp_vcpu->vcpu.arch.mdcr_el2	= host_vcpu->arch.mdcr_el2;
131 	hyp_vcpu->vcpu.arch.hcr_el2 &= ~(HCR_TWI | HCR_TWE);
132 	hyp_vcpu->vcpu.arch.hcr_el2 |= READ_ONCE(host_vcpu->arch.hcr_el2) &
133 						 (HCR_TWI | HCR_TWE);
134 
135 	hyp_vcpu->vcpu.arch.iflags	= host_vcpu->arch.iflags;
136 
137 	hyp_vcpu->vcpu.arch.vsesr_el2	= host_vcpu->arch.vsesr_el2;
138 
139 	hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3;
140 }
141 
sync_hyp_vcpu(struct pkvm_hyp_vcpu * hyp_vcpu)142 static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
143 {
144 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
145 	struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3;
146 	struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3;
147 	unsigned int i;
148 
149 	fpsimd_sve_sync(&hyp_vcpu->vcpu);
150 	sync_debug_state(hyp_vcpu);
151 
152 	host_vcpu->arch.ctxt		= hyp_vcpu->vcpu.arch.ctxt;
153 
154 	host_vcpu->arch.hcr_el2		= hyp_vcpu->vcpu.arch.hcr_el2;
155 
156 	host_vcpu->arch.fault		= hyp_vcpu->vcpu.arch.fault;
157 
158 	host_vcpu->arch.iflags		= hyp_vcpu->vcpu.arch.iflags;
159 
160 	host_cpu_if->vgic_hcr		= hyp_cpu_if->vgic_hcr;
161 	for (i = 0; i < hyp_cpu_if->used_lrs; ++i)
162 		host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i];
163 }
164 
handle___pkvm_vcpu_load(struct kvm_cpu_context * host_ctxt)165 static void handle___pkvm_vcpu_load(struct kvm_cpu_context *host_ctxt)
166 {
167 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
168 	DECLARE_REG(unsigned int, vcpu_idx, host_ctxt, 2);
169 	DECLARE_REG(u64, hcr_el2, host_ctxt, 3);
170 	struct pkvm_hyp_vcpu *hyp_vcpu;
171 
172 	if (!is_protected_kvm_enabled())
173 		return;
174 
175 	hyp_vcpu = pkvm_load_hyp_vcpu(handle, vcpu_idx);
176 	if (!hyp_vcpu)
177 		return;
178 
179 	if (pkvm_hyp_vcpu_is_protected(hyp_vcpu)) {
180 		/* Propagate WFx trapping flags */
181 		hyp_vcpu->vcpu.arch.hcr_el2 &= ~(HCR_TWE | HCR_TWI);
182 		hyp_vcpu->vcpu.arch.hcr_el2 |= hcr_el2 & (HCR_TWE | HCR_TWI);
183 	}
184 }
185 
handle___pkvm_vcpu_put(struct kvm_cpu_context * host_ctxt)186 static void handle___pkvm_vcpu_put(struct kvm_cpu_context *host_ctxt)
187 {
188 	struct pkvm_hyp_vcpu *hyp_vcpu;
189 
190 	if (!is_protected_kvm_enabled())
191 		return;
192 
193 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
194 	if (hyp_vcpu)
195 		pkvm_put_hyp_vcpu(hyp_vcpu);
196 }
197 
handle___kvm_vcpu_run(struct kvm_cpu_context * host_ctxt)198 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
199 {
200 	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1);
201 	int ret;
202 
203 	if (unlikely(is_protected_kvm_enabled())) {
204 		struct pkvm_hyp_vcpu *hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
205 
206 		/*
207 		 * KVM (and pKVM) doesn't support SME guests for now, and
208 		 * ensures that SME features aren't enabled in pstate when
209 		 * loading a vcpu. Therefore, if SME features enabled the host
210 		 * is misbehaving.
211 		 */
212 		if (unlikely(system_supports_sme() && read_sysreg_s(SYS_SVCR))) {
213 			ret = -EINVAL;
214 			goto out;
215 		}
216 
217 		if (!hyp_vcpu) {
218 			ret = -EINVAL;
219 			goto out;
220 		}
221 
222 		flush_hyp_vcpu(hyp_vcpu);
223 
224 		ret = __kvm_vcpu_run(&hyp_vcpu->vcpu);
225 
226 		sync_hyp_vcpu(hyp_vcpu);
227 	} else {
228 		struct kvm_vcpu *vcpu = kern_hyp_va(host_vcpu);
229 
230 		/* The host is fully trusted, run its vCPU directly. */
231 		fpsimd_lazy_switch_to_guest(vcpu);
232 		ret = __kvm_vcpu_run(vcpu);
233 		fpsimd_lazy_switch_to_host(vcpu);
234 	}
235 out:
236 	cpu_reg(host_ctxt, 1) =  ret;
237 }
238 
pkvm_refill_memcache(struct pkvm_hyp_vcpu * hyp_vcpu)239 static int pkvm_refill_memcache(struct pkvm_hyp_vcpu *hyp_vcpu)
240 {
241 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
242 
243 	return refill_memcache(&hyp_vcpu->vcpu.arch.pkvm_memcache,
244 			       host_vcpu->arch.pkvm_memcache.nr_pages,
245 			       &host_vcpu->arch.pkvm_memcache);
246 }
247 
handle___pkvm_host_share_guest(struct kvm_cpu_context * host_ctxt)248 static void handle___pkvm_host_share_guest(struct kvm_cpu_context *host_ctxt)
249 {
250 	DECLARE_REG(u64, pfn, host_ctxt, 1);
251 	DECLARE_REG(u64, gfn, host_ctxt, 2);
252 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
253 	struct pkvm_hyp_vcpu *hyp_vcpu;
254 	int ret = -EINVAL;
255 
256 	if (!is_protected_kvm_enabled())
257 		goto out;
258 
259 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
260 	if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu))
261 		goto out;
262 
263 	ret = pkvm_refill_memcache(hyp_vcpu);
264 	if (ret)
265 		goto out;
266 
267 	ret = __pkvm_host_share_guest(pfn, gfn, hyp_vcpu, prot);
268 out:
269 	cpu_reg(host_ctxt, 1) =  ret;
270 }
271 
handle___pkvm_host_unshare_guest(struct kvm_cpu_context * host_ctxt)272 static void handle___pkvm_host_unshare_guest(struct kvm_cpu_context *host_ctxt)
273 {
274 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
275 	DECLARE_REG(u64, gfn, host_ctxt, 2);
276 	struct pkvm_hyp_vm *hyp_vm;
277 	int ret = -EINVAL;
278 
279 	if (!is_protected_kvm_enabled())
280 		goto out;
281 
282 	hyp_vm = get_np_pkvm_hyp_vm(handle);
283 	if (!hyp_vm)
284 		goto out;
285 
286 	ret = __pkvm_host_unshare_guest(gfn, hyp_vm);
287 	put_pkvm_hyp_vm(hyp_vm);
288 out:
289 	cpu_reg(host_ctxt, 1) =  ret;
290 }
291 
handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context * host_ctxt)292 static void handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context *host_ctxt)
293 {
294 	DECLARE_REG(u64, gfn, host_ctxt, 1);
295 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 2);
296 	struct pkvm_hyp_vcpu *hyp_vcpu;
297 	int ret = -EINVAL;
298 
299 	if (!is_protected_kvm_enabled())
300 		goto out;
301 
302 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
303 	if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu))
304 		goto out;
305 
306 	ret = __pkvm_host_relax_perms_guest(gfn, hyp_vcpu, prot);
307 out:
308 	cpu_reg(host_ctxt, 1) = ret;
309 }
310 
handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context * host_ctxt)311 static void handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context *host_ctxt)
312 {
313 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
314 	DECLARE_REG(u64, gfn, host_ctxt, 2);
315 	struct pkvm_hyp_vm *hyp_vm;
316 	int ret = -EINVAL;
317 
318 	if (!is_protected_kvm_enabled())
319 		goto out;
320 
321 	hyp_vm = get_np_pkvm_hyp_vm(handle);
322 	if (!hyp_vm)
323 		goto out;
324 
325 	ret = __pkvm_host_wrprotect_guest(gfn, hyp_vm);
326 	put_pkvm_hyp_vm(hyp_vm);
327 out:
328 	cpu_reg(host_ctxt, 1) = ret;
329 }
330 
handle___pkvm_host_test_clear_young_guest(struct kvm_cpu_context * host_ctxt)331 static void handle___pkvm_host_test_clear_young_guest(struct kvm_cpu_context *host_ctxt)
332 {
333 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
334 	DECLARE_REG(u64, gfn, host_ctxt, 2);
335 	DECLARE_REG(bool, mkold, host_ctxt, 3);
336 	struct pkvm_hyp_vm *hyp_vm;
337 	int ret = -EINVAL;
338 
339 	if (!is_protected_kvm_enabled())
340 		goto out;
341 
342 	hyp_vm = get_np_pkvm_hyp_vm(handle);
343 	if (!hyp_vm)
344 		goto out;
345 
346 	ret = __pkvm_host_test_clear_young_guest(gfn, mkold, hyp_vm);
347 	put_pkvm_hyp_vm(hyp_vm);
348 out:
349 	cpu_reg(host_ctxt, 1) = ret;
350 }
351 
handle___pkvm_host_mkyoung_guest(struct kvm_cpu_context * host_ctxt)352 static void handle___pkvm_host_mkyoung_guest(struct kvm_cpu_context *host_ctxt)
353 {
354 	DECLARE_REG(u64, gfn, host_ctxt, 1);
355 	struct pkvm_hyp_vcpu *hyp_vcpu;
356 	int ret = -EINVAL;
357 
358 	if (!is_protected_kvm_enabled())
359 		goto out;
360 
361 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
362 	if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu))
363 		goto out;
364 
365 	ret = __pkvm_host_mkyoung_guest(gfn, hyp_vcpu);
366 out:
367 	cpu_reg(host_ctxt, 1) =  ret;
368 }
369 
handle___kvm_adjust_pc(struct kvm_cpu_context * host_ctxt)370 static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt)
371 {
372 	DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
373 
374 	__kvm_adjust_pc(kern_hyp_va(vcpu));
375 }
376 
handle___kvm_flush_vm_context(struct kvm_cpu_context * host_ctxt)377 static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt)
378 {
379 	__kvm_flush_vm_context();
380 }
381 
handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context * host_ctxt)382 static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt)
383 {
384 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
385 	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
386 	DECLARE_REG(int, level, host_ctxt, 3);
387 
388 	__kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level);
389 }
390 
handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context * host_ctxt)391 static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt)
392 {
393 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
394 	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
395 	DECLARE_REG(int, level, host_ctxt, 3);
396 
397 	__kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level);
398 }
399 
400 static void
handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context * host_ctxt)401 handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt)
402 {
403 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
404 	DECLARE_REG(phys_addr_t, start, host_ctxt, 2);
405 	DECLARE_REG(unsigned long, pages, host_ctxt, 3);
406 
407 	__kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages);
408 }
409 
handle___kvm_tlb_flush_vmid(struct kvm_cpu_context * host_ctxt)410 static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
411 {
412 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
413 
414 	__kvm_tlb_flush_vmid(kern_hyp_va(mmu));
415 }
416 
handle___pkvm_tlb_flush_vmid(struct kvm_cpu_context * host_ctxt)417 static void handle___pkvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
418 {
419 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
420 	struct pkvm_hyp_vm *hyp_vm;
421 
422 	if (!is_protected_kvm_enabled())
423 		return;
424 
425 	hyp_vm = get_np_pkvm_hyp_vm(handle);
426 	if (!hyp_vm)
427 		return;
428 
429 	__kvm_tlb_flush_vmid(&hyp_vm->kvm.arch.mmu);
430 	put_pkvm_hyp_vm(hyp_vm);
431 }
432 
handle___kvm_flush_cpu_context(struct kvm_cpu_context * host_ctxt)433 static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt)
434 {
435 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
436 
437 	__kvm_flush_cpu_context(kern_hyp_va(mmu));
438 }
439 
handle___kvm_timer_set_cntvoff(struct kvm_cpu_context * host_ctxt)440 static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
441 {
442 	__kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1));
443 }
444 
handle___kvm_enable_ssbs(struct kvm_cpu_context * host_ctxt)445 static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
446 {
447 	u64 tmp;
448 
449 	tmp = read_sysreg_el2(SYS_SCTLR);
450 	tmp |= SCTLR_ELx_DSSBS;
451 	write_sysreg_el2(tmp, SYS_SCTLR);
452 }
453 
handle___vgic_v3_get_gic_config(struct kvm_cpu_context * host_ctxt)454 static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
455 {
456 	cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
457 }
458 
handle___vgic_v3_init_lrs(struct kvm_cpu_context * host_ctxt)459 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
460 {
461 	__vgic_v3_init_lrs();
462 }
463 
handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context * host_ctxt)464 static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
465 {
466 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
467 
468 	__vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if));
469 }
470 
handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context * host_ctxt)471 static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
472 {
473 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
474 
475 	__vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if));
476 }
477 
handle___pkvm_init(struct kvm_cpu_context * host_ctxt)478 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
479 {
480 	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
481 	DECLARE_REG(unsigned long, size, host_ctxt, 2);
482 	DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
483 	DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
484 	DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
485 
486 	/*
487 	 * __pkvm_init() will return only if an error occurred, otherwise it
488 	 * will tail-call in __pkvm_init_finalise() which will have to deal
489 	 * with the host context directly.
490 	 */
491 	cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
492 					    hyp_va_bits);
493 }
494 
handle___pkvm_cpu_set_vector(struct kvm_cpu_context * host_ctxt)495 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
496 {
497 	DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1);
498 
499 	cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot);
500 }
501 
handle___pkvm_host_share_hyp(struct kvm_cpu_context * host_ctxt)502 static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt)
503 {
504 	DECLARE_REG(u64, pfn, host_ctxt, 1);
505 
506 	cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn);
507 }
508 
handle___pkvm_host_unshare_hyp(struct kvm_cpu_context * host_ctxt)509 static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt)
510 {
511 	DECLARE_REG(u64, pfn, host_ctxt, 1);
512 
513 	cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn);
514 }
515 
handle___pkvm_create_private_mapping(struct kvm_cpu_context * host_ctxt)516 static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt)
517 {
518 	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
519 	DECLARE_REG(size_t, size, host_ctxt, 2);
520 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
521 
522 	/*
523 	 * __pkvm_create_private_mapping() populates a pointer with the
524 	 * hypervisor start address of the allocation.
525 	 *
526 	 * However, handle___pkvm_create_private_mapping() hypercall crosses the
527 	 * EL1/EL2 boundary so the pointer would not be valid in this context.
528 	 *
529 	 * Instead pass the allocation address as the return value (or return
530 	 * ERR_PTR() on failure).
531 	 */
532 	unsigned long haddr;
533 	int err = __pkvm_create_private_mapping(phys, size, prot, &haddr);
534 
535 	if (err)
536 		haddr = (unsigned long)ERR_PTR(err);
537 
538 	cpu_reg(host_ctxt, 1) = haddr;
539 }
540 
handle___pkvm_prot_finalize(struct kvm_cpu_context * host_ctxt)541 static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
542 {
543 	cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
544 }
545 
handle___pkvm_init_vm(struct kvm_cpu_context * host_ctxt)546 static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt)
547 {
548 	DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
549 	DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2);
550 	DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3);
551 
552 	host_kvm = kern_hyp_va(host_kvm);
553 	cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva);
554 }
555 
handle___pkvm_init_vcpu(struct kvm_cpu_context * host_ctxt)556 static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt)
557 {
558 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
559 	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2);
560 	DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3);
561 
562 	host_vcpu = kern_hyp_va(host_vcpu);
563 	cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva);
564 }
565 
handle___pkvm_teardown_vm(struct kvm_cpu_context * host_ctxt)566 static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt)
567 {
568 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
569 
570 	cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle);
571 }
572 
573 typedef void (*hcall_t)(struct kvm_cpu_context *);
574 
575 #define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
576 
577 static const hcall_t host_hcall[] = {
578 	/* ___kvm_hyp_init */
579 	HANDLE_FUNC(__pkvm_init),
580 	HANDLE_FUNC(__pkvm_create_private_mapping),
581 	HANDLE_FUNC(__pkvm_cpu_set_vector),
582 	HANDLE_FUNC(__kvm_enable_ssbs),
583 	HANDLE_FUNC(__vgic_v3_init_lrs),
584 	HANDLE_FUNC(__vgic_v3_get_gic_config),
585 	HANDLE_FUNC(__pkvm_prot_finalize),
586 
587 	HANDLE_FUNC(__pkvm_host_share_hyp),
588 	HANDLE_FUNC(__pkvm_host_unshare_hyp),
589 	HANDLE_FUNC(__pkvm_host_share_guest),
590 	HANDLE_FUNC(__pkvm_host_unshare_guest),
591 	HANDLE_FUNC(__pkvm_host_relax_perms_guest),
592 	HANDLE_FUNC(__pkvm_host_wrprotect_guest),
593 	HANDLE_FUNC(__pkvm_host_test_clear_young_guest),
594 	HANDLE_FUNC(__pkvm_host_mkyoung_guest),
595 	HANDLE_FUNC(__kvm_adjust_pc),
596 	HANDLE_FUNC(__kvm_vcpu_run),
597 	HANDLE_FUNC(__kvm_flush_vm_context),
598 	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
599 	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh),
600 	HANDLE_FUNC(__kvm_tlb_flush_vmid),
601 	HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
602 	HANDLE_FUNC(__kvm_flush_cpu_context),
603 	HANDLE_FUNC(__kvm_timer_set_cntvoff),
604 	HANDLE_FUNC(__vgic_v3_save_vmcr_aprs),
605 	HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs),
606 	HANDLE_FUNC(__pkvm_init_vm),
607 	HANDLE_FUNC(__pkvm_init_vcpu),
608 	HANDLE_FUNC(__pkvm_teardown_vm),
609 	HANDLE_FUNC(__pkvm_vcpu_load),
610 	HANDLE_FUNC(__pkvm_vcpu_put),
611 	HANDLE_FUNC(__pkvm_tlb_flush_vmid),
612 };
613 
handle_host_hcall(struct kvm_cpu_context * host_ctxt)614 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
615 {
616 	DECLARE_REG(unsigned long, id, host_ctxt, 0);
617 	unsigned long hcall_min = 0;
618 	hcall_t hfn;
619 
620 	/*
621 	 * If pKVM has been initialised then reject any calls to the
622 	 * early "privileged" hypercalls. Note that we cannot reject
623 	 * calls to __pkvm_prot_finalize for two reasons: (1) The static
624 	 * key used to determine initialisation must be toggled prior to
625 	 * finalisation and (2) finalisation is performed on a per-CPU
626 	 * basis. This is all fine, however, since __pkvm_prot_finalize
627 	 * returns -EPERM after the first call for a given CPU.
628 	 */
629 	if (static_branch_unlikely(&kvm_protected_mode_initialized))
630 		hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize;
631 
632 	id &= ~ARM_SMCCC_CALL_HINTS;
633 	id -= KVM_HOST_SMCCC_ID(0);
634 
635 	if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall)))
636 		goto inval;
637 
638 	hfn = host_hcall[id];
639 	if (unlikely(!hfn))
640 		goto inval;
641 
642 	cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
643 	hfn(host_ctxt);
644 
645 	return;
646 inval:
647 	cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;
648 }
649 
default_host_smc_handler(struct kvm_cpu_context * host_ctxt)650 static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt)
651 {
652 	__kvm_hyp_host_forward_smc(host_ctxt);
653 }
654 
handle_host_smc(struct kvm_cpu_context * host_ctxt)655 static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
656 {
657 	DECLARE_REG(u64, func_id, host_ctxt, 0);
658 	bool handled;
659 
660 	func_id &= ~ARM_SMCCC_CALL_HINTS;
661 
662 	handled = kvm_host_psci_handler(host_ctxt, func_id);
663 	if (!handled)
664 		handled = kvm_host_ffa_handler(host_ctxt, func_id);
665 	if (!handled)
666 		default_host_smc_handler(host_ctxt);
667 
668 	/* SMC was trapped, move ELR past the current PC. */
669 	kvm_skip_host_instr();
670 }
671 
handle_trap(struct kvm_cpu_context * host_ctxt)672 void handle_trap(struct kvm_cpu_context *host_ctxt)
673 {
674 	u64 esr = read_sysreg_el2(SYS_ESR);
675 
676 	switch (ESR_ELx_EC(esr)) {
677 	case ESR_ELx_EC_HVC64:
678 		handle_host_hcall(host_ctxt);
679 		break;
680 	case ESR_ELx_EC_SMC64:
681 		handle_host_smc(host_ctxt);
682 		break;
683 	case ESR_ELx_EC_IABT_LOW:
684 	case ESR_ELx_EC_DABT_LOW:
685 		handle_host_mem_abort(host_ctxt);
686 		break;
687 	default:
688 		BUG();
689 	}
690 }
691