xref: /linux/arch/arm64/kvm/hyp/nvhe/hyp-main.c (revision e669e322c52c49c161e46492963e64319fbb53a8)
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_assign_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 	/*
73 	 * Traps have been disabled by __deactivate_cptr_traps(), but there
74 	 * hasn't necessarily been a context synchronization event yet.
75 	 */
76 	isb();
77 
78 	if (vcpu_has_sve(vcpu))
79 		__hyp_sve_save_guest(vcpu);
80 	else
81 		__fpsimd_save_state(&vcpu->arch.ctxt.fp_regs);
82 
83 	has_fpmr = kvm_has_fpmr(kern_hyp_va(vcpu->kvm));
84 	if (has_fpmr)
85 		__vcpu_assign_sys_reg(vcpu, FPMR, read_sysreg_s(SYS_FPMR));
86 
87 	if (system_supports_sve())
88 		__hyp_sve_restore_host();
89 	else
90 		__fpsimd_restore_state(host_data_ptr(host_ctxt.fp_regs));
91 
92 	if (has_fpmr)
93 		write_sysreg_s(*host_data_ptr(fpmr), SYS_FPMR);
94 
95 	*host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED;
96 }
97 
flush_debug_state(struct pkvm_hyp_vcpu * hyp_vcpu)98 static void flush_debug_state(struct pkvm_hyp_vcpu *hyp_vcpu)
99 {
100 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
101 
102 	hyp_vcpu->vcpu.arch.debug_owner = host_vcpu->arch.debug_owner;
103 
104 	if (kvm_guest_owns_debug_regs(&hyp_vcpu->vcpu))
105 		hyp_vcpu->vcpu.arch.vcpu_debug_state = host_vcpu->arch.vcpu_debug_state;
106 	else if (kvm_host_owns_debug_regs(&hyp_vcpu->vcpu))
107 		hyp_vcpu->vcpu.arch.external_debug_state = host_vcpu->arch.external_debug_state;
108 }
109 
sync_debug_state(struct pkvm_hyp_vcpu * hyp_vcpu)110 static void sync_debug_state(struct pkvm_hyp_vcpu *hyp_vcpu)
111 {
112 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
113 
114 	if (kvm_guest_owns_debug_regs(&hyp_vcpu->vcpu))
115 		host_vcpu->arch.vcpu_debug_state = hyp_vcpu->vcpu.arch.vcpu_debug_state;
116 	else if (kvm_host_owns_debug_regs(&hyp_vcpu->vcpu))
117 		host_vcpu->arch.external_debug_state = hyp_vcpu->vcpu.arch.external_debug_state;
118 }
119 
flush_hyp_vcpu(struct pkvm_hyp_vcpu * hyp_vcpu)120 static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
121 {
122 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
123 
124 	fpsimd_sve_flush();
125 	flush_debug_state(hyp_vcpu);
126 
127 	hyp_vcpu->vcpu.arch.ctxt	= host_vcpu->arch.ctxt;
128 
129 	hyp_vcpu->vcpu.arch.mdcr_el2	= host_vcpu->arch.mdcr_el2;
130 	hyp_vcpu->vcpu.arch.hcr_el2 &= ~(HCR_TWI | HCR_TWE);
131 	hyp_vcpu->vcpu.arch.hcr_el2 |= READ_ONCE(host_vcpu->arch.hcr_el2) &
132 						 (HCR_TWI | HCR_TWE);
133 
134 	hyp_vcpu->vcpu.arch.iflags	= host_vcpu->arch.iflags;
135 
136 	hyp_vcpu->vcpu.arch.vsesr_el2	= host_vcpu->arch.vsesr_el2;
137 
138 	hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3;
139 }
140 
sync_hyp_vcpu(struct pkvm_hyp_vcpu * hyp_vcpu)141 static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
142 {
143 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
144 	struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3;
145 	struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3;
146 	unsigned int i;
147 
148 	fpsimd_sve_sync(&hyp_vcpu->vcpu);
149 	sync_debug_state(hyp_vcpu);
150 
151 	host_vcpu->arch.ctxt		= hyp_vcpu->vcpu.arch.ctxt;
152 
153 	host_vcpu->arch.hcr_el2		= hyp_vcpu->vcpu.arch.hcr_el2;
154 
155 	host_vcpu->arch.fault		= hyp_vcpu->vcpu.arch.fault;
156 
157 	host_vcpu->arch.iflags		= hyp_vcpu->vcpu.arch.iflags;
158 
159 	host_cpu_if->vgic_hcr		= hyp_cpu_if->vgic_hcr;
160 	for (i = 0; i < hyp_cpu_if->used_lrs; ++i)
161 		host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i];
162 }
163 
handle___pkvm_vcpu_load(struct kvm_cpu_context * host_ctxt)164 static void handle___pkvm_vcpu_load(struct kvm_cpu_context *host_ctxt)
165 {
166 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
167 	DECLARE_REG(unsigned int, vcpu_idx, host_ctxt, 2);
168 	DECLARE_REG(u64, hcr_el2, host_ctxt, 3);
169 	struct pkvm_hyp_vcpu *hyp_vcpu;
170 
171 	if (!is_protected_kvm_enabled())
172 		return;
173 
174 	hyp_vcpu = pkvm_load_hyp_vcpu(handle, vcpu_idx);
175 	if (!hyp_vcpu)
176 		return;
177 
178 	if (pkvm_hyp_vcpu_is_protected(hyp_vcpu)) {
179 		/* Propagate WFx trapping flags */
180 		hyp_vcpu->vcpu.arch.hcr_el2 &= ~(HCR_TWE | HCR_TWI);
181 		hyp_vcpu->vcpu.arch.hcr_el2 |= hcr_el2 & (HCR_TWE | HCR_TWI);
182 	}
183 }
184 
handle___pkvm_vcpu_put(struct kvm_cpu_context * host_ctxt)185 static void handle___pkvm_vcpu_put(struct kvm_cpu_context *host_ctxt)
186 {
187 	struct pkvm_hyp_vcpu *hyp_vcpu;
188 
189 	if (!is_protected_kvm_enabled())
190 		return;
191 
192 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
193 	if (hyp_vcpu)
194 		pkvm_put_hyp_vcpu(hyp_vcpu);
195 }
196 
handle___kvm_vcpu_run(struct kvm_cpu_context * host_ctxt)197 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
198 {
199 	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1);
200 	int ret;
201 
202 	if (unlikely(is_protected_kvm_enabled())) {
203 		struct pkvm_hyp_vcpu *hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
204 
205 		/*
206 		 * KVM (and pKVM) doesn't support SME guests for now, and
207 		 * ensures that SME features aren't enabled in pstate when
208 		 * loading a vcpu. Therefore, if SME features enabled the host
209 		 * is misbehaving.
210 		 */
211 		if (unlikely(system_supports_sme() && read_sysreg_s(SYS_SVCR))) {
212 			ret = -EINVAL;
213 			goto out;
214 		}
215 
216 		if (!hyp_vcpu) {
217 			ret = -EINVAL;
218 			goto out;
219 		}
220 
221 		flush_hyp_vcpu(hyp_vcpu);
222 
223 		ret = __kvm_vcpu_run(&hyp_vcpu->vcpu);
224 
225 		sync_hyp_vcpu(hyp_vcpu);
226 	} else {
227 		struct kvm_vcpu *vcpu = kern_hyp_va(host_vcpu);
228 
229 		/* The host is fully trusted, run its vCPU directly. */
230 		fpsimd_lazy_switch_to_guest(vcpu);
231 		ret = __kvm_vcpu_run(vcpu);
232 		fpsimd_lazy_switch_to_host(vcpu);
233 	}
234 out:
235 	cpu_reg(host_ctxt, 1) =  ret;
236 }
237 
pkvm_refill_memcache(struct pkvm_hyp_vcpu * hyp_vcpu)238 static int pkvm_refill_memcache(struct pkvm_hyp_vcpu *hyp_vcpu)
239 {
240 	struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
241 
242 	return refill_memcache(&hyp_vcpu->vcpu.arch.pkvm_memcache,
243 			       host_vcpu->arch.pkvm_memcache.nr_pages,
244 			       &host_vcpu->arch.pkvm_memcache);
245 }
246 
handle___pkvm_host_share_guest(struct kvm_cpu_context * host_ctxt)247 static void handle___pkvm_host_share_guest(struct kvm_cpu_context *host_ctxt)
248 {
249 	DECLARE_REG(u64, pfn, host_ctxt, 1);
250 	DECLARE_REG(u64, gfn, host_ctxt, 2);
251 	DECLARE_REG(u64, nr_pages, host_ctxt, 3);
252 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 4);
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, nr_pages, 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 	DECLARE_REG(u64, nr_pages, host_ctxt, 3);
277 	struct pkvm_hyp_vm *hyp_vm;
278 	int ret = -EINVAL;
279 
280 	if (!is_protected_kvm_enabled())
281 		goto out;
282 
283 	hyp_vm = get_np_pkvm_hyp_vm(handle);
284 	if (!hyp_vm)
285 		goto out;
286 
287 	ret = __pkvm_host_unshare_guest(gfn, nr_pages, hyp_vm);
288 	put_pkvm_hyp_vm(hyp_vm);
289 out:
290 	cpu_reg(host_ctxt, 1) =  ret;
291 }
292 
handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context * host_ctxt)293 static void handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context *host_ctxt)
294 {
295 	DECLARE_REG(u64, gfn, host_ctxt, 1);
296 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 2);
297 	struct pkvm_hyp_vcpu *hyp_vcpu;
298 	int ret = -EINVAL;
299 
300 	if (!is_protected_kvm_enabled())
301 		goto out;
302 
303 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
304 	if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu))
305 		goto out;
306 
307 	ret = __pkvm_host_relax_perms_guest(gfn, hyp_vcpu, prot);
308 out:
309 	cpu_reg(host_ctxt, 1) = ret;
310 }
311 
handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context * host_ctxt)312 static void handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context *host_ctxt)
313 {
314 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
315 	DECLARE_REG(u64, gfn, host_ctxt, 2);
316 	DECLARE_REG(u64, nr_pages, host_ctxt, 3);
317 	struct pkvm_hyp_vm *hyp_vm;
318 	int ret = -EINVAL;
319 
320 	if (!is_protected_kvm_enabled())
321 		goto out;
322 
323 	hyp_vm = get_np_pkvm_hyp_vm(handle);
324 	if (!hyp_vm)
325 		goto out;
326 
327 	ret = __pkvm_host_wrprotect_guest(gfn, nr_pages, hyp_vm);
328 	put_pkvm_hyp_vm(hyp_vm);
329 out:
330 	cpu_reg(host_ctxt, 1) = ret;
331 }
332 
handle___pkvm_host_test_clear_young_guest(struct kvm_cpu_context * host_ctxt)333 static void handle___pkvm_host_test_clear_young_guest(struct kvm_cpu_context *host_ctxt)
334 {
335 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
336 	DECLARE_REG(u64, gfn, host_ctxt, 2);
337 	DECLARE_REG(u64, nr_pages, host_ctxt, 3);
338 	DECLARE_REG(bool, mkold, host_ctxt, 4);
339 	struct pkvm_hyp_vm *hyp_vm;
340 	int ret = -EINVAL;
341 
342 	if (!is_protected_kvm_enabled())
343 		goto out;
344 
345 	hyp_vm = get_np_pkvm_hyp_vm(handle);
346 	if (!hyp_vm)
347 		goto out;
348 
349 	ret = __pkvm_host_test_clear_young_guest(gfn, nr_pages, mkold, hyp_vm);
350 	put_pkvm_hyp_vm(hyp_vm);
351 out:
352 	cpu_reg(host_ctxt, 1) = ret;
353 }
354 
handle___pkvm_host_mkyoung_guest(struct kvm_cpu_context * host_ctxt)355 static void handle___pkvm_host_mkyoung_guest(struct kvm_cpu_context *host_ctxt)
356 {
357 	DECLARE_REG(u64, gfn, host_ctxt, 1);
358 	struct pkvm_hyp_vcpu *hyp_vcpu;
359 	int ret = -EINVAL;
360 
361 	if (!is_protected_kvm_enabled())
362 		goto out;
363 
364 	hyp_vcpu = pkvm_get_loaded_hyp_vcpu();
365 	if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu))
366 		goto out;
367 
368 	ret = __pkvm_host_mkyoung_guest(gfn, hyp_vcpu);
369 out:
370 	cpu_reg(host_ctxt, 1) =  ret;
371 }
372 
handle___kvm_adjust_pc(struct kvm_cpu_context * host_ctxt)373 static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt)
374 {
375 	DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
376 
377 	__kvm_adjust_pc(kern_hyp_va(vcpu));
378 }
379 
handle___kvm_flush_vm_context(struct kvm_cpu_context * host_ctxt)380 static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt)
381 {
382 	__kvm_flush_vm_context();
383 }
384 
handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context * host_ctxt)385 static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt)
386 {
387 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
388 	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
389 	DECLARE_REG(int, level, host_ctxt, 3);
390 
391 	__kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level);
392 }
393 
handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context * host_ctxt)394 static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt)
395 {
396 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
397 	DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
398 	DECLARE_REG(int, level, host_ctxt, 3);
399 
400 	__kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level);
401 }
402 
403 static void
handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context * host_ctxt)404 handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt)
405 {
406 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
407 	DECLARE_REG(phys_addr_t, start, host_ctxt, 2);
408 	DECLARE_REG(unsigned long, pages, host_ctxt, 3);
409 
410 	__kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages);
411 }
412 
handle___kvm_tlb_flush_vmid(struct kvm_cpu_context * host_ctxt)413 static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
414 {
415 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
416 
417 	__kvm_tlb_flush_vmid(kern_hyp_va(mmu));
418 }
419 
handle___pkvm_tlb_flush_vmid(struct kvm_cpu_context * host_ctxt)420 static void handle___pkvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
421 {
422 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
423 	struct pkvm_hyp_vm *hyp_vm;
424 
425 	if (!is_protected_kvm_enabled())
426 		return;
427 
428 	hyp_vm = get_np_pkvm_hyp_vm(handle);
429 	if (!hyp_vm)
430 		return;
431 
432 	__kvm_tlb_flush_vmid(&hyp_vm->kvm.arch.mmu);
433 	put_pkvm_hyp_vm(hyp_vm);
434 }
435 
handle___kvm_flush_cpu_context(struct kvm_cpu_context * host_ctxt)436 static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt)
437 {
438 	DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
439 
440 	__kvm_flush_cpu_context(kern_hyp_va(mmu));
441 }
442 
handle___kvm_timer_set_cntvoff(struct kvm_cpu_context * host_ctxt)443 static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
444 {
445 	__kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1));
446 }
447 
handle___kvm_enable_ssbs(struct kvm_cpu_context * host_ctxt)448 static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
449 {
450 	u64 tmp;
451 
452 	tmp = read_sysreg_el2(SYS_SCTLR);
453 	tmp |= SCTLR_ELx_DSSBS;
454 	write_sysreg_el2(tmp, SYS_SCTLR);
455 }
456 
handle___vgic_v3_get_gic_config(struct kvm_cpu_context * host_ctxt)457 static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
458 {
459 	cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
460 }
461 
handle___vgic_v3_init_lrs(struct kvm_cpu_context * host_ctxt)462 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
463 {
464 	__vgic_v3_init_lrs();
465 }
466 
handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context * host_ctxt)467 static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
468 {
469 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
470 
471 	__vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if));
472 }
473 
handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context * host_ctxt)474 static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
475 {
476 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
477 
478 	__vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if));
479 }
480 
handle___pkvm_init(struct kvm_cpu_context * host_ctxt)481 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
482 {
483 	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
484 	DECLARE_REG(unsigned long, size, host_ctxt, 2);
485 	DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
486 	DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
487 	DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
488 
489 	/*
490 	 * __pkvm_init() will return only if an error occurred, otherwise it
491 	 * will tail-call in __pkvm_init_finalise() which will have to deal
492 	 * with the host context directly.
493 	 */
494 	cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
495 					    hyp_va_bits);
496 }
497 
handle___pkvm_cpu_set_vector(struct kvm_cpu_context * host_ctxt)498 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
499 {
500 	DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1);
501 
502 	cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot);
503 }
504 
handle___pkvm_host_share_hyp(struct kvm_cpu_context * host_ctxt)505 static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt)
506 {
507 	DECLARE_REG(u64, pfn, host_ctxt, 1);
508 
509 	cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn);
510 }
511 
handle___pkvm_host_unshare_hyp(struct kvm_cpu_context * host_ctxt)512 static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt)
513 {
514 	DECLARE_REG(u64, pfn, host_ctxt, 1);
515 
516 	cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn);
517 }
518 
handle___pkvm_create_private_mapping(struct kvm_cpu_context * host_ctxt)519 static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt)
520 {
521 	DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
522 	DECLARE_REG(size_t, size, host_ctxt, 2);
523 	DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
524 
525 	/*
526 	 * __pkvm_create_private_mapping() populates a pointer with the
527 	 * hypervisor start address of the allocation.
528 	 *
529 	 * However, handle___pkvm_create_private_mapping() hypercall crosses the
530 	 * EL1/EL2 boundary so the pointer would not be valid in this context.
531 	 *
532 	 * Instead pass the allocation address as the return value (or return
533 	 * ERR_PTR() on failure).
534 	 */
535 	unsigned long haddr;
536 	int err = __pkvm_create_private_mapping(phys, size, prot, &haddr);
537 
538 	if (err)
539 		haddr = (unsigned long)ERR_PTR(err);
540 
541 	cpu_reg(host_ctxt, 1) = haddr;
542 }
543 
handle___pkvm_prot_finalize(struct kvm_cpu_context * host_ctxt)544 static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
545 {
546 	cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
547 }
548 
handle___pkvm_init_vm(struct kvm_cpu_context * host_ctxt)549 static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt)
550 {
551 	DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
552 	DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2);
553 	DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3);
554 
555 	host_kvm = kern_hyp_va(host_kvm);
556 	cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva);
557 }
558 
handle___pkvm_init_vcpu(struct kvm_cpu_context * host_ctxt)559 static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt)
560 {
561 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
562 	DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2);
563 	DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3);
564 
565 	host_vcpu = kern_hyp_va(host_vcpu);
566 	cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva);
567 }
568 
handle___pkvm_teardown_vm(struct kvm_cpu_context * host_ctxt)569 static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt)
570 {
571 	DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
572 
573 	cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle);
574 }
575 
576 typedef void (*hcall_t)(struct kvm_cpu_context *);
577 
578 #define HANDLE_FUNC(x)	[__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
579 
580 static const hcall_t host_hcall[] = {
581 	/* ___kvm_hyp_init */
582 	HANDLE_FUNC(__pkvm_init),
583 	HANDLE_FUNC(__pkvm_create_private_mapping),
584 	HANDLE_FUNC(__pkvm_cpu_set_vector),
585 	HANDLE_FUNC(__kvm_enable_ssbs),
586 	HANDLE_FUNC(__vgic_v3_init_lrs),
587 	HANDLE_FUNC(__vgic_v3_get_gic_config),
588 	HANDLE_FUNC(__pkvm_prot_finalize),
589 
590 	HANDLE_FUNC(__pkvm_host_share_hyp),
591 	HANDLE_FUNC(__pkvm_host_unshare_hyp),
592 	HANDLE_FUNC(__pkvm_host_share_guest),
593 	HANDLE_FUNC(__pkvm_host_unshare_guest),
594 	HANDLE_FUNC(__pkvm_host_relax_perms_guest),
595 	HANDLE_FUNC(__pkvm_host_wrprotect_guest),
596 	HANDLE_FUNC(__pkvm_host_test_clear_young_guest),
597 	HANDLE_FUNC(__pkvm_host_mkyoung_guest),
598 	HANDLE_FUNC(__kvm_adjust_pc),
599 	HANDLE_FUNC(__kvm_vcpu_run),
600 	HANDLE_FUNC(__kvm_flush_vm_context),
601 	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
602 	HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh),
603 	HANDLE_FUNC(__kvm_tlb_flush_vmid),
604 	HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
605 	HANDLE_FUNC(__kvm_flush_cpu_context),
606 	HANDLE_FUNC(__kvm_timer_set_cntvoff),
607 	HANDLE_FUNC(__vgic_v3_save_vmcr_aprs),
608 	HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs),
609 	HANDLE_FUNC(__pkvm_init_vm),
610 	HANDLE_FUNC(__pkvm_init_vcpu),
611 	HANDLE_FUNC(__pkvm_teardown_vm),
612 	HANDLE_FUNC(__pkvm_vcpu_load),
613 	HANDLE_FUNC(__pkvm_vcpu_put),
614 	HANDLE_FUNC(__pkvm_tlb_flush_vmid),
615 };
616 
handle_host_hcall(struct kvm_cpu_context * host_ctxt)617 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
618 {
619 	DECLARE_REG(unsigned long, id, host_ctxt, 0);
620 	unsigned long hcall_min = 0;
621 	hcall_t hfn;
622 
623 	/*
624 	 * If pKVM has been initialised then reject any calls to the
625 	 * early "privileged" hypercalls. Note that we cannot reject
626 	 * calls to __pkvm_prot_finalize for two reasons: (1) The static
627 	 * key used to determine initialisation must be toggled prior to
628 	 * finalisation and (2) finalisation is performed on a per-CPU
629 	 * basis. This is all fine, however, since __pkvm_prot_finalize
630 	 * returns -EPERM after the first call for a given CPU.
631 	 */
632 	if (static_branch_unlikely(&kvm_protected_mode_initialized))
633 		hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize;
634 
635 	id &= ~ARM_SMCCC_CALL_HINTS;
636 	id -= KVM_HOST_SMCCC_ID(0);
637 
638 	if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall)))
639 		goto inval;
640 
641 	hfn = host_hcall[id];
642 	if (unlikely(!hfn))
643 		goto inval;
644 
645 	cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
646 	hfn(host_ctxt);
647 
648 	return;
649 inval:
650 	cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;
651 }
652 
default_host_smc_handler(struct kvm_cpu_context * host_ctxt)653 static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt)
654 {
655 	__kvm_hyp_host_forward_smc(host_ctxt);
656 }
657 
handle_host_smc(struct kvm_cpu_context * host_ctxt)658 static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
659 {
660 	DECLARE_REG(u64, func_id, host_ctxt, 0);
661 	bool handled;
662 
663 	func_id &= ~ARM_SMCCC_CALL_HINTS;
664 
665 	handled = kvm_host_psci_handler(host_ctxt, func_id);
666 	if (!handled)
667 		handled = kvm_host_ffa_handler(host_ctxt, func_id);
668 	if (!handled)
669 		default_host_smc_handler(host_ctxt);
670 
671 	/* SMC was trapped, move ELR past the current PC. */
672 	kvm_skip_host_instr();
673 }
674 
handle_trap(struct kvm_cpu_context * host_ctxt)675 void handle_trap(struct kvm_cpu_context *host_ctxt)
676 {
677 	u64 esr = read_sysreg_el2(SYS_ESR);
678 
679 	switch (ESR_ELx_EC(esr)) {
680 	case ESR_ELx_EC_HVC64:
681 		handle_host_hcall(host_ctxt);
682 		break;
683 	case ESR_ELx_EC_SMC64:
684 		handle_host_smc(host_ctxt);
685 		break;
686 	case ESR_ELx_EC_IABT_LOW:
687 	case ESR_ELx_EC_DABT_LOW:
688 		handle_host_mem_abort(host_ctxt);
689 		break;
690 	default:
691 		BUG();
692 	}
693 }
694