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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2016 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
.arch_extension virt
.text
.pushsection .hyp.text, "ax"
#define USR_REGS_OFFSET (CPU_CTXT_GP_REGS + GP_REGS_USR)
/* int __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host) */
ENTRY(__guest_enter)
@ Save host registers
add r1, r1, #(USR_REGS_OFFSET + S_R4)
stm r1!, {r4-r12}
str lr, [r1, #4] @ Skip SP_usr (already saved)
@ Restore guest registers
add r0, r0, #(VCPU_GUEST_CTXT + USR_REGS_OFFSET + S_R0)
ldr lr, [r0, #S_LR]
ldm r0, {r0-r12}
clrex
eret
ENDPROC(__guest_enter)
ENTRY(__guest_exit)
/*
* return convention:
* guest r0, r1, r2 saved on the stack
* r0: vcpu pointer
* r1: exception code
*/
add r2, r0, #(VCPU_GUEST_CTXT + USR_REGS_OFFSET + S_R3)
stm r2!, {r3-r12}
str lr, [r2, #4]
add r2, r0, #(VCPU_GUEST_CTXT + USR_REGS_OFFSET + S_R0)
pop {r3, r4, r5} @ r0, r1, r2
stm r2, {r3-r5}
ldr r0, [r0, #VCPU_HOST_CTXT]
add r0, r0, #(USR_REGS_OFFSET + S_R4)
ldm r0!, {r4-r12}
ldr lr, [r0, #4]
mov r0, r1
mrs r1, SPSR
mrs r2, ELR_hyp
mrc p15, 4, r3, c5, c2, 0 @ HSR
/*
* Force loads and stores to complete before unmasking aborts
* and forcing the delivery of the exception. This gives us a
* single instruction window, which the handler will try to
* match.
*/
dsb sy
cpsie a
.global abort_guest_exit_start
abort_guest_exit_start:
isb
.global abort_guest_exit_end
abort_guest_exit_end:
/*
* If we took an abort, r0[31] will be set, and cmp will set
* the N bit in PSTATE.
*/
cmp r0, #0
msrmi SPSR_cxsf, r1
msrmi ELR_hyp, r2
mcrmi p15, 4, r3, c5, c2, 0 @ HSR
bx lr
ENDPROC(__guest_exit)
/*
* If VFPv3 support is not available, then we will not switch the VFP
* registers; however cp10 and cp11 accesses will still trap and fallback
* to the regular coprocessor emulation code, which currently will
* inject an undefined exception to the guest.
*/
#ifdef CONFIG_VFPv3
ENTRY(__vfp_guest_restore)
push {r3, r4, lr}
@ NEON/VFP used. Turn on VFP access.
mrc p15, 4, r1, c1, c1, 2 @ HCPTR
bic r1, r1, #(HCPTR_TCP(10) | HCPTR_TCP(11))
mcr p15, 4, r1, c1, c1, 2 @ HCPTR
isb
@ Switch VFP/NEON hardware state to the guest's
mov r4, r0
ldr r0, [r0, #VCPU_HOST_CTXT]
add r0, r0, #CPU_CTXT_VFP
bl __vfp_save_state
add r0, r4, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
bl __vfp_restore_state
pop {r3, r4, lr}
pop {r0, r1, r2}
clrex
eret
ENDPROC(__vfp_guest_restore)
#endif
.popsection
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