1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012-2015 - ARM Ltd
4  * Author: Marc Zyngier <[email protected]>
5  */
6 
7 #ifndef __ARM64_KVM_HYP_SYSREG_SR_H__
8 #define __ARM64_KVM_HYP_SYSREG_SR_H__
9 
10 #include <linux/compiler.h>
11 #include <linux/kvm_host.h>
12 
13 #include <asm/kprobes.h>
14 #include <asm/kvm_asm.h>
15 #include <asm/kvm_emulate.h>
16 #include <asm/kvm_hyp.h>
17 #include <asm/kvm_mmu.h>
18 
19 static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt);
20 
ctxt_to_vcpu(struct kvm_cpu_context * ctxt)21 static inline struct kvm_vcpu *ctxt_to_vcpu(struct kvm_cpu_context *ctxt)
22 {
23 	struct kvm_vcpu *vcpu = ctxt->__hyp_running_vcpu;
24 
25 	if (!vcpu)
26 		vcpu = container_of(ctxt, struct kvm_vcpu, arch.ctxt);
27 
28 	return vcpu;
29 }
30 
ctxt_is_guest(struct kvm_cpu_context * ctxt)31 static inline bool ctxt_is_guest(struct kvm_cpu_context *ctxt)
32 {
33 	return host_data_ptr(host_ctxt) != ctxt;
34 }
35 
ctxt_mdscr_el1(struct kvm_cpu_context * ctxt)36 static inline u64 *ctxt_mdscr_el1(struct kvm_cpu_context *ctxt)
37 {
38 	struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
39 
40 	if (ctxt_is_guest(ctxt) && kvm_host_owns_debug_regs(vcpu))
41 		return &vcpu->arch.external_mdscr_el1;
42 
43 	return &ctxt_sys_reg(ctxt, MDSCR_EL1);
44 }
45 
__sysreg_save_common_state(struct kvm_cpu_context * ctxt)46 static inline void __sysreg_save_common_state(struct kvm_cpu_context *ctxt)
47 {
48 	*ctxt_mdscr_el1(ctxt)	= read_sysreg(mdscr_el1);
49 
50 	// POR_EL0 can affect uaccess, so must be saved/restored early.
51 	if (ctxt_has_s1poe(ctxt))
52 		ctxt_sys_reg(ctxt, POR_EL0)	= read_sysreg_s(SYS_POR_EL0);
53 }
54 
__sysreg_save_user_state(struct kvm_cpu_context * ctxt)55 static inline void __sysreg_save_user_state(struct kvm_cpu_context *ctxt)
56 {
57 	ctxt_sys_reg(ctxt, TPIDR_EL0)	= read_sysreg(tpidr_el0);
58 	ctxt_sys_reg(ctxt, TPIDRRO_EL0)	= read_sysreg(tpidrro_el0);
59 }
60 
ctxt_has_mte(struct kvm_cpu_context * ctxt)61 static inline bool ctxt_has_mte(struct kvm_cpu_context *ctxt)
62 {
63 	struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
64 
65 	return kvm_has_mte(kern_hyp_va(vcpu->kvm));
66 }
67 
ctxt_has_s1pie(struct kvm_cpu_context * ctxt)68 static inline bool ctxt_has_s1pie(struct kvm_cpu_context *ctxt)
69 {
70 	struct kvm_vcpu *vcpu;
71 
72 	if (!cpus_have_final_cap(ARM64_HAS_S1PIE))
73 		return false;
74 
75 	vcpu = ctxt_to_vcpu(ctxt);
76 	return kvm_has_s1pie(kern_hyp_va(vcpu->kvm));
77 }
78 
ctxt_has_tcrx(struct kvm_cpu_context * ctxt)79 static inline bool ctxt_has_tcrx(struct kvm_cpu_context *ctxt)
80 {
81 	struct kvm_vcpu *vcpu;
82 
83 	if (!cpus_have_final_cap(ARM64_HAS_TCR2))
84 		return false;
85 
86 	vcpu = ctxt_to_vcpu(ctxt);
87 	return kvm_has_tcr2(kern_hyp_va(vcpu->kvm));
88 }
89 
ctxt_has_s1poe(struct kvm_cpu_context * ctxt)90 static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt)
91 {
92 	struct kvm_vcpu *vcpu;
93 
94 	if (!system_supports_poe())
95 		return false;
96 
97 	vcpu = ctxt_to_vcpu(ctxt);
98 	return kvm_has_s1poe(kern_hyp_va(vcpu->kvm));
99 }
100 
__sysreg_save_el1_state(struct kvm_cpu_context * ctxt)101 static inline void __sysreg_save_el1_state(struct kvm_cpu_context *ctxt)
102 {
103 	ctxt_sys_reg(ctxt, SCTLR_EL1)	= read_sysreg_el1(SYS_SCTLR);
104 	ctxt_sys_reg(ctxt, CPACR_EL1)	= read_sysreg_el1(SYS_CPACR);
105 	ctxt_sys_reg(ctxt, TTBR0_EL1)	= read_sysreg_el1(SYS_TTBR0);
106 	ctxt_sys_reg(ctxt, TTBR1_EL1)	= read_sysreg_el1(SYS_TTBR1);
107 	ctxt_sys_reg(ctxt, TCR_EL1)	= read_sysreg_el1(SYS_TCR);
108 	if (ctxt_has_tcrx(ctxt)) {
109 		ctxt_sys_reg(ctxt, TCR2_EL1)	= read_sysreg_el1(SYS_TCR2);
110 
111 		if (ctxt_has_s1pie(ctxt)) {
112 			ctxt_sys_reg(ctxt, PIR_EL1)	= read_sysreg_el1(SYS_PIR);
113 			ctxt_sys_reg(ctxt, PIRE0_EL1)	= read_sysreg_el1(SYS_PIRE0);
114 		}
115 
116 		if (ctxt_has_s1poe(ctxt))
117 			ctxt_sys_reg(ctxt, POR_EL1)	= read_sysreg_el1(SYS_POR);
118 	}
119 	ctxt_sys_reg(ctxt, ESR_EL1)	= read_sysreg_el1(SYS_ESR);
120 	ctxt_sys_reg(ctxt, AFSR0_EL1)	= read_sysreg_el1(SYS_AFSR0);
121 	ctxt_sys_reg(ctxt, AFSR1_EL1)	= read_sysreg_el1(SYS_AFSR1);
122 	ctxt_sys_reg(ctxt, FAR_EL1)	= read_sysreg_el1(SYS_FAR);
123 	ctxt_sys_reg(ctxt, MAIR_EL1)	= read_sysreg_el1(SYS_MAIR);
124 	ctxt_sys_reg(ctxt, VBAR_EL1)	= read_sysreg_el1(SYS_VBAR);
125 	ctxt_sys_reg(ctxt, CONTEXTIDR_EL1) = read_sysreg_el1(SYS_CONTEXTIDR);
126 	ctxt_sys_reg(ctxt, AMAIR_EL1)	= read_sysreg_el1(SYS_AMAIR);
127 	ctxt_sys_reg(ctxt, CNTKCTL_EL1)	= read_sysreg_el1(SYS_CNTKCTL);
128 	ctxt_sys_reg(ctxt, PAR_EL1)	= read_sysreg_par();
129 	ctxt_sys_reg(ctxt, TPIDR_EL1)	= read_sysreg(tpidr_el1);
130 
131 	if (ctxt_has_mte(ctxt)) {
132 		ctxt_sys_reg(ctxt, TFSR_EL1) = read_sysreg_el1(SYS_TFSR);
133 		ctxt_sys_reg(ctxt, TFSRE0_EL1) = read_sysreg_s(SYS_TFSRE0_EL1);
134 	}
135 
136 	ctxt_sys_reg(ctxt, SP_EL1)	= read_sysreg(sp_el1);
137 	ctxt_sys_reg(ctxt, ELR_EL1)	= read_sysreg_el1(SYS_ELR);
138 	ctxt_sys_reg(ctxt, SPSR_EL1)	= read_sysreg_el1(SYS_SPSR);
139 }
140 
__sysreg_save_el2_return_state(struct kvm_cpu_context * ctxt)141 static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt)
142 {
143 	ctxt->regs.pc			= read_sysreg_el2(SYS_ELR);
144 	/*
145 	 * Guest PSTATE gets saved at guest fixup time in all
146 	 * cases. We still need to handle the nVHE host side here.
147 	 */
148 	if (!has_vhe() && ctxt->__hyp_running_vcpu)
149 		ctxt->regs.pstate	= read_sysreg_el2(SYS_SPSR);
150 
151 	if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
152 		ctxt_sys_reg(ctxt, DISR_EL1) = read_sysreg_s(SYS_VDISR_EL2);
153 }
154 
__sysreg_restore_common_state(struct kvm_cpu_context * ctxt)155 static inline void __sysreg_restore_common_state(struct kvm_cpu_context *ctxt)
156 {
157 	write_sysreg(*ctxt_mdscr_el1(ctxt),  mdscr_el1);
158 
159 	// POR_EL0 can affect uaccess, so must be saved/restored early.
160 	if (ctxt_has_s1poe(ctxt))
161 		write_sysreg_s(ctxt_sys_reg(ctxt, POR_EL0),	SYS_POR_EL0);
162 }
163 
__sysreg_restore_user_state(struct kvm_cpu_context * ctxt)164 static inline void __sysreg_restore_user_state(struct kvm_cpu_context *ctxt)
165 {
166 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL0),	tpidr_el0);
167 	write_sysreg(ctxt_sys_reg(ctxt, TPIDRRO_EL0),	tpidrro_el0);
168 }
169 
__sysreg_restore_el1_state(struct kvm_cpu_context * ctxt,u64 mpidr)170 static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt,
171 					      u64 mpidr)
172 {
173 	write_sysreg(mpidr,				vmpidr_el2);
174 
175 	if (has_vhe() ||
176 	    !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
177 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
178 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
179 	} else	if (!ctxt->__hyp_running_vcpu) {
180 		/*
181 		 * Must only be done for guest registers, hence the context
182 		 * test. We're coming from the host, so SCTLR.M is already
183 		 * set. Pairs with nVHE's __activate_traps().
184 		 */
185 		write_sysreg_el1((ctxt_sys_reg(ctxt, TCR_EL1) |
186 				  TCR_EPD1_MASK | TCR_EPD0_MASK),
187 				 SYS_TCR);
188 		isb();
189 	}
190 
191 	write_sysreg_el1(ctxt_sys_reg(ctxt, CPACR_EL1),	SYS_CPACR);
192 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR0_EL1),	SYS_TTBR0);
193 	write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR1_EL1),	SYS_TTBR1);
194 	if (ctxt_has_tcrx(ctxt)) {
195 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR2_EL1),	SYS_TCR2);
196 
197 		if (ctxt_has_s1pie(ctxt)) {
198 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIR_EL1),	SYS_PIR);
199 			write_sysreg_el1(ctxt_sys_reg(ctxt, PIRE0_EL1),	SYS_PIRE0);
200 		}
201 
202 		if (ctxt_has_s1poe(ctxt))
203 			write_sysreg_el1(ctxt_sys_reg(ctxt, POR_EL1),	SYS_POR);
204 	}
205 	write_sysreg_el1(ctxt_sys_reg(ctxt, ESR_EL1),	SYS_ESR);
206 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR0_EL1),	SYS_AFSR0);
207 	write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR1_EL1),	SYS_AFSR1);
208 	write_sysreg_el1(ctxt_sys_reg(ctxt, FAR_EL1),	SYS_FAR);
209 	write_sysreg_el1(ctxt_sys_reg(ctxt, MAIR_EL1),	SYS_MAIR);
210 	write_sysreg_el1(ctxt_sys_reg(ctxt, VBAR_EL1),	SYS_VBAR);
211 	write_sysreg_el1(ctxt_sys_reg(ctxt, CONTEXTIDR_EL1), SYS_CONTEXTIDR);
212 	write_sysreg_el1(ctxt_sys_reg(ctxt, AMAIR_EL1),	SYS_AMAIR);
213 	write_sysreg_el1(ctxt_sys_reg(ctxt, CNTKCTL_EL1), SYS_CNTKCTL);
214 	write_sysreg(ctxt_sys_reg(ctxt, PAR_EL1),	par_el1);
215 	write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL1),	tpidr_el1);
216 
217 	if (ctxt_has_mte(ctxt)) {
218 		write_sysreg_el1(ctxt_sys_reg(ctxt, TFSR_EL1), SYS_TFSR);
219 		write_sysreg_s(ctxt_sys_reg(ctxt, TFSRE0_EL1), SYS_TFSRE0_EL1);
220 	}
221 
222 	if (!has_vhe() &&
223 	    cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) &&
224 	    ctxt->__hyp_running_vcpu) {
225 		/*
226 		 * Must only be done for host registers, hence the context
227 		 * test. Pairs with nVHE's __deactivate_traps().
228 		 */
229 		isb();
230 		/*
231 		 * At this stage, and thanks to the above isb(), S2 is
232 		 * deconfigured and disabled. We can now restore the host's
233 		 * S1 configuration: SCTLR, and only then TCR.
234 		 */
235 		write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL1),	SYS_SCTLR);
236 		isb();
237 		write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL1),	SYS_TCR);
238 	}
239 
240 	write_sysreg(ctxt_sys_reg(ctxt, SP_EL1),	sp_el1);
241 	write_sysreg_el1(ctxt_sys_reg(ctxt, ELR_EL1),	SYS_ELR);
242 	write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1),	SYS_SPSR);
243 }
244 
245 /* Read the VCPU state's PSTATE, but translate (v)EL2 to EL1. */
to_hw_pstate(const struct kvm_cpu_context * ctxt)246 static inline u64 to_hw_pstate(const struct kvm_cpu_context *ctxt)
247 {
248 	u64 mode = ctxt->regs.pstate & (PSR_MODE_MASK | PSR_MODE32_BIT);
249 
250 	switch (mode) {
251 	case PSR_MODE_EL2t:
252 		mode = PSR_MODE_EL1t;
253 		break;
254 	case PSR_MODE_EL2h:
255 		mode = PSR_MODE_EL1h;
256 		break;
257 	}
258 
259 	return (ctxt->regs.pstate & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
260 }
261 
__sysreg_restore_el2_return_state(struct kvm_cpu_context * ctxt)262 static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt)
263 {
264 	u64 pstate = to_hw_pstate(ctxt);
265 	u64 mode = pstate & PSR_AA32_MODE_MASK;
266 
267 	/*
268 	 * Safety check to ensure we're setting the CPU up to enter the guest
269 	 * in a less privileged mode.
270 	 *
271 	 * If we are attempting a return to EL2 or higher in AArch64 state,
272 	 * program SPSR_EL2 with M=EL2h and the IL bit set which ensures that
273 	 * we'll take an illegal exception state exception immediately after
274 	 * the ERET to the guest.  Attempts to return to AArch32 Hyp will
275 	 * result in an illegal exception return because EL2's execution state
276 	 * is determined by SCR_EL3.RW.
277 	 */
278 	if (!(mode & PSR_MODE32_BIT) && mode >= PSR_MODE_EL2t)
279 		pstate = PSR_MODE_EL2h | PSR_IL_BIT;
280 
281 	write_sysreg_el2(ctxt->regs.pc,			SYS_ELR);
282 	write_sysreg_el2(pstate,			SYS_SPSR);
283 
284 	if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
285 		write_sysreg_s(ctxt_sys_reg(ctxt, DISR_EL1), SYS_VDISR_EL2);
286 }
287 
__sysreg32_save_state(struct kvm_vcpu * vcpu)288 static inline void __sysreg32_save_state(struct kvm_vcpu *vcpu)
289 {
290 	if (!vcpu_el1_is_32bit(vcpu))
291 		return;
292 
293 	vcpu->arch.ctxt.spsr_abt = read_sysreg(spsr_abt);
294 	vcpu->arch.ctxt.spsr_und = read_sysreg(spsr_und);
295 	vcpu->arch.ctxt.spsr_irq = read_sysreg(spsr_irq);
296 	vcpu->arch.ctxt.spsr_fiq = read_sysreg(spsr_fiq);
297 
298 	__vcpu_sys_reg(vcpu, DACR32_EL2) = read_sysreg(dacr32_el2);
299 	__vcpu_sys_reg(vcpu, IFSR32_EL2) = read_sysreg(ifsr32_el2);
300 
301 	if (has_vhe() || kvm_debug_regs_in_use(vcpu))
302 		__vcpu_sys_reg(vcpu, DBGVCR32_EL2) = read_sysreg(dbgvcr32_el2);
303 }
304 
__sysreg32_restore_state(struct kvm_vcpu * vcpu)305 static inline void __sysreg32_restore_state(struct kvm_vcpu *vcpu)
306 {
307 	if (!vcpu_el1_is_32bit(vcpu))
308 		return;
309 
310 	write_sysreg(vcpu->arch.ctxt.spsr_abt, spsr_abt);
311 	write_sysreg(vcpu->arch.ctxt.spsr_und, spsr_und);
312 	write_sysreg(vcpu->arch.ctxt.spsr_irq, spsr_irq);
313 	write_sysreg(vcpu->arch.ctxt.spsr_fiq, spsr_fiq);
314 
315 	write_sysreg(__vcpu_sys_reg(vcpu, DACR32_EL2), dacr32_el2);
316 	write_sysreg(__vcpu_sys_reg(vcpu, IFSR32_EL2), ifsr32_el2);
317 
318 	if (has_vhe() || kvm_debug_regs_in_use(vcpu))
319 		write_sysreg(__vcpu_sys_reg(vcpu, DBGVCR32_EL2), dbgvcr32_el2);
320 }
321 
322 #endif /* __ARM64_KVM_HYP_SYSREG_SR_H__ */
323