linux_dsm_epyc7002/arch/arm64/kvm/sys_regs.h
Marc Zyngier 2072d29c46 arm64: KVM: allows discrimination of AArch32 sysreg access
The current handling of AArch32 trapping is slightly less than
perfect, as it is not possible (from a handler point of view)
to distinguish it from an AArch64 access, nor to tell a 32bit
from a 64bit access either.

Fix this by introducing two additional flags:
- is_aarch32: true if the access was made in AArch32 mode
- is_32bit: true if is_aarch32 == true and a MCR/MRC instruction
  was used to perform the access (as opposed to MCRR/MRRC).

This allows a handler to cover all the possible conditions in which
a system register gets trapped.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-03-03 01:15:21 +00:00

141 lines
3.5 KiB
C

/*
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* Derived from arch/arm/kvm/coproc.h
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Authors: 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, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ARM64_KVM_SYS_REGS_LOCAL_H__
#define __ARM64_KVM_SYS_REGS_LOCAL_H__
struct sys_reg_params {
u8 Op0;
u8 Op1;
u8 CRn;
u8 CRm;
u8 Op2;
u8 Rt;
bool is_write;
bool is_aarch32;
bool is_32bit; /* Only valid if is_aarch32 is true */
};
struct sys_reg_desc {
/* MRS/MSR instruction which accesses it. */
u8 Op0;
u8 Op1;
u8 CRn;
u8 CRm;
u8 Op2;
/* Trapped access from guest, if non-NULL. */
bool (*access)(struct kvm_vcpu *,
const struct sys_reg_params *,
const struct sys_reg_desc *);
/* Initialization for vcpu. */
void (*reset)(struct kvm_vcpu *, const struct sys_reg_desc *);
/* Index into sys_reg[], or 0 if we don't need to save it. */
int reg;
/* Value (usually reset value) */
u64 val;
};
static inline void print_sys_reg_instr(const struct sys_reg_params *p)
{
/* Look, we even formatted it for you to paste into the table! */
kvm_pr_unimpl(" { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
}
static inline bool ignore_write(struct kvm_vcpu *vcpu,
const struct sys_reg_params *p)
{
return true;
}
static inline bool read_zero(struct kvm_vcpu *vcpu,
const struct sys_reg_params *p)
{
*vcpu_reg(vcpu, p->Rt) = 0;
return true;
}
static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
const struct sys_reg_params *params)
{
kvm_debug("sys_reg write to read-only register at: %lx\n",
*vcpu_pc(vcpu));
print_sys_reg_instr(params);
return false;
}
static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
const struct sys_reg_params *params)
{
kvm_debug("sys_reg read to write-only register at: %lx\n",
*vcpu_pc(vcpu));
print_sys_reg_instr(params);
return false;
}
/* Reset functions */
static inline void reset_unknown(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
BUG_ON(!r->reg);
BUG_ON(r->reg >= NR_SYS_REGS);
vcpu_sys_reg(vcpu, r->reg) = 0x1de7ec7edbadc0deULL;
}
static inline void reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
BUG_ON(!r->reg);
BUG_ON(r->reg >= NR_SYS_REGS);
vcpu_sys_reg(vcpu, r->reg) = r->val;
}
static inline int cmp_sys_reg(const struct sys_reg_desc *i1,
const struct sys_reg_desc *i2)
{
BUG_ON(i1 == i2);
if (!i1)
return 1;
else if (!i2)
return -1;
if (i1->Op0 != i2->Op0)
return i1->Op0 - i2->Op0;
if (i1->Op1 != i2->Op1)
return i1->Op1 - i2->Op1;
if (i1->CRn != i2->CRn)
return i1->CRn - i2->CRn;
if (i1->CRm != i2->CRm)
return i1->CRm - i2->CRm;
return i1->Op2 - i2->Op2;
}
#define Op0(_x) .Op0 = _x
#define Op1(_x) .Op1 = _x
#define CRn(_x) .CRn = _x
#define CRm(_x) .CRm = _x
#define Op2(_x) .Op2 = _x
#endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */