linux/arch/arm/include/asm/kvm_emulate.h
Christoffer Dall 5b3e5e5bf2 KVM: ARM: Emulation framework and CP15 emulation
Adds a new important function in the main KVM/ARM code called
handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns
from guest execution. This function examines the Hyp-Syndrome-Register
(HSR), which contains information telling KVM what caused the exit from
the guest.

Some of the reasons for an exit are CP15 accesses, which are
not allowed from the guest and this commit handles these exits by
emulating the intended operation in software and skipping the guest
instruction.

Minor notes about the coproc register reset:
1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our
   table, at cost of 4 bytes per vcpu.

2) Added comments on the table indicating how we handle each register, for
   simplicity of understanding.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-23 13:29:13 -05:00

57 lines
1.9 KiB
C

/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.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, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef __ARM_KVM_EMULATE_H__
#define __ARM_KVM_EMULATE_H__
#include <linux/kvm_host.h>
#include <asm/kvm_asm.h>
u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num);
u32 *vcpu_spsr(struct kvm_vcpu *vcpu);
int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run);
void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr);
void kvm_inject_undefined(struct kvm_vcpu *vcpu);
void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
static inline u32 *vcpu_pc(struct kvm_vcpu *vcpu)
{
return (u32 *)&vcpu->arch.regs.usr_regs.ARM_pc;
}
static inline u32 *vcpu_cpsr(struct kvm_vcpu *vcpu)
{
return (u32 *)&vcpu->arch.regs.usr_regs.ARM_cpsr;
}
static inline bool mode_has_spsr(struct kvm_vcpu *vcpu)
{
unsigned long cpsr_mode = vcpu->arch.regs.usr_regs.ARM_cpsr & MODE_MASK;
return (cpsr_mode > USR_MODE && cpsr_mode < SYSTEM_MODE);
}
static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu)
{
unsigned long cpsr_mode = vcpu->arch.regs.usr_regs.ARM_cpsr & MODE_MASK;
return cpsr_mode > USR_MODE;;
}
#endif /* __ARM_KVM_EMULATE_H__ */