kernel_optimize_test/arch/arm64/kvm/sys_regs.h
Andrew Jones 912dee5726 KVM: arm64: Check RAZ visibility in ID register accessors
The instruction encodings of ID registers are preallocated. Until an
encoding is assigned a purpose the register is RAZ. KVM's general ID
register accessor functions already support both paths, RAZ or not.
If for each ID register we can determine if it's RAZ or not, then all
ID registers can build on the general functions. The register visibility
function allows us to check whether a register should be completely
hidden or not, extending it to also report when the register should
be RAZ or not allows us to use it for ID registers as well.

Check for RAZ visibility in the ID register accessor functions,
allowing the RAZ case to be handled in a generic way for all system
registers.

The new REG_RAZ flag will be used in a later patch. This patch has
no intended functional change.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201105091022.15373-4-drjones@redhat.com
2020-11-06 16:00:29 +00:00

169 lines
4.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* 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>
*/
#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;
u64 regval;
bool is_write;
bool is_aarch32;
bool is_32bit; /* Only valid if is_aarch32 is true */
};
struct sys_reg_desc {
/* Sysreg string for debug */
const char *name;
/* 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 *,
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;
/* Custom get/set_user functions, fallback to generic if NULL */
int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
const struct kvm_one_reg *reg, void __user *uaddr);
int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
const struct kvm_one_reg *reg, void __user *uaddr);
/* Return mask of REG_* runtime visibility overrides */
unsigned int (*visibility)(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd);
};
#define REG_HIDDEN (1 << 0) /* hidden from userspace and guest */
#define REG_RAZ (1 << 1) /* RAZ from userspace and guest */
static __printf(2, 3)
inline void print_sys_reg_msg(const struct sys_reg_params *p,
char *fmt, ...)
{
va_list va;
va_start(va, fmt);
/* Look, we even formatted it for you to paste into the table! */
kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
&(struct va_format){ fmt, &va },
p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
va_end(va);
}
static inline void print_sys_reg_instr(const struct sys_reg_params *p)
{
/* GCC warns on an empty format string */
print_sys_reg_msg(p, "%s", "");
}
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,
struct sys_reg_params *p)
{
p->regval = 0;
return true;
}
/* 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 bool sysreg_hidden(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
if (likely(!r->visibility))
return false;
return r->visibility(vcpu, r) & REG_HIDDEN;
}
static inline bool sysreg_visible_as_raz(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
if (likely(!r->visibility))
return false;
return r->visibility(vcpu, r) & REG_RAZ;
}
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;
}
const struct sys_reg_desc *find_reg_by_id(u64 id,
struct sys_reg_params *params,
const struct sys_reg_desc table[],
unsigned int num);
#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
#define SYS_DESC(reg) \
.name = #reg, \
Op0(sys_reg_Op0(reg)), Op1(sys_reg_Op1(reg)), \
CRn(sys_reg_CRn(reg)), CRm(sys_reg_CRm(reg)), \
Op2(sys_reg_Op2(reg))
#endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */