1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
#include <asm/fpsimdmacros.h>
#include <asm/kvm.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
#define CPU_GP_REG_OFFSET(x) (CPU_GP_REGS + x)
#define CPU_XREG_OFFSET(x) CPU_GP_REG_OFFSET(CPU_USER_PT_REGS + 8*x)
.text
.pushsection .hyp.text, "ax"
.macro save_callee_saved_regs ctxt
stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)]
.endm
.macro restore_callee_saved_regs ctxt
ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)]
.endm
/*
* u64 __guest_enter(struct kvm_vcpu *vcpu,
* struct kvm_cpu_context *host_ctxt);
*/
ENTRY(__guest_enter)
// x0: vcpu
// x1: host context
// x2-x17: clobbered by macros
// x18: guest context
// Store the host regs
save_callee_saved_regs x1
// Store the host_ctxt for use at exit time
str x1, [sp, #-16]!
add x18, x0, #VCPU_CONTEXT
// Restore guest regs x0-x17
ldp x0, x1, [x18, #CPU_XREG_OFFSET(0)]
ldp x2, x3, [x18, #CPU_XREG_OFFSET(2)]
ldp x4, x5, [x18, #CPU_XREG_OFFSET(4)]
ldp x6, x7, [x18, #CPU_XREG_OFFSET(6)]
ldp x8, x9, [x18, #CPU_XREG_OFFSET(8)]
ldp x10, x11, [x18, #CPU_XREG_OFFSET(10)]
ldp x12, x13, [x18, #CPU_XREG_OFFSET(12)]
ldp x14, x15, [x18, #CPU_XREG_OFFSET(14)]
ldp x16, x17, [x18, #CPU_XREG_OFFSET(16)]
// Restore guest regs x19-x29, lr
restore_callee_saved_regs x18
// Restore guest reg x18
ldr x18, [x18, #CPU_XREG_OFFSET(18)]
// Do not touch any register after this!
eret
ENDPROC(__guest_enter)
ENTRY(__guest_exit)
// x0: return code
// x1: vcpu
// x2-x29,lr: vcpu regs
// vcpu x0-x1 on the stack
add x1, x1, #VCPU_CONTEXT
ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
// Store the guest regs x2 and x3
stp x2, x3, [x1, #CPU_XREG_OFFSET(2)]
// Retrieve the guest regs x0-x1 from the stack
ldp x2, x3, [sp], #16 // x0, x1
// Store the guest regs x0-x1 and x4-x18
stp x2, x3, [x1, #CPU_XREG_OFFSET(0)]
stp x4, x5, [x1, #CPU_XREG_OFFSET(4)]
stp x6, x7, [x1, #CPU_XREG_OFFSET(6)]
stp x8, x9, [x1, #CPU_XREG_OFFSET(8)]
stp x10, x11, [x1, #CPU_XREG_OFFSET(10)]
stp x12, x13, [x1, #CPU_XREG_OFFSET(12)]
stp x14, x15, [x1, #CPU_XREG_OFFSET(14)]
stp x16, x17, [x1, #CPU_XREG_OFFSET(16)]
str x18, [x1, #CPU_XREG_OFFSET(18)]
// Store the guest regs x19-x29, lr
save_callee_saved_regs x1
// Restore the host_ctxt from the stack
ldr x2, [sp], #16
// Now restore the host regs
restore_callee_saved_regs x2
// If we have a pending asynchronous abort, now is the
// time to find out. From your VAXorcist book, page 666:
// "Threaten me not, oh Evil one! For I speak with
// the power of DEC, and I command thee to show thyself!"
mrs x2, elr_el2
mrs x3, esr_el2
mrs x4, spsr_el2
mov x5, x0
dsb sy // Synchronize against in-flight ld/st
msr daifclr, #4 // Unmask aborts
// This is our single instruction exception window. A pending
// SError is guaranteed to occur at the earliest when we unmask
// it, and at the latest just after the ISB.
.global abort_guest_exit_start
abort_guest_exit_start:
isb
.global abort_guest_exit_end
abort_guest_exit_end:
// If the exception took place, restore the EL1 exception
// context so that we can report some information.
// Merge the exception code with the SError pending bit.
tbz x0, #ARM_EXIT_WITH_SERROR_BIT, 1f
msr elr_el2, x2
msr esr_el2, x3
msr spsr_el2, x4
orr x0, x0, x5
1: ret
ENDPROC(__guest_exit)
ENTRY(__fpsimd_guest_restore)
stp x2, x3, [sp, #-16]!
stp x4, lr, [sp, #-16]!
alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
mrs x2, cptr_el2
bic x2, x2, #CPTR_EL2_TFP
msr cptr_el2, x2
alternative_else
mrs x2, cpacr_el1
orr x2, x2, #CPACR_EL1_FPEN
msr cpacr_el1, x2
alternative_endif
isb
mrs x3, tpidr_el2
ldr x0, [x3, #VCPU_HOST_CONTEXT]
kern_hyp_va x0
add x0, x0, #CPU_GP_REG_OFFSET(CPU_FP_REGS)
bl __fpsimd_save_state
add x2, x3, #VCPU_CONTEXT
add x0, x2, #CPU_GP_REG_OFFSET(CPU_FP_REGS)
bl __fpsimd_restore_state
// Skip restoring fpexc32 for AArch64 guests
mrs x1, hcr_el2
tbnz x1, #HCR_RW_SHIFT, 1f
ldr x4, [x3, #VCPU_FPEXC32_EL2]
msr fpexc32_el2, x4
1:
ldp x4, lr, [sp], #16
ldp x2, x3, [sp], #16
ldp x0, x1, [sp], #16
eret
ENDPROC(__fpsimd_guest_restore)
|
