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linux/arch/arm64/kvm/sys_regs.h

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arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
/*
* 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;
arm64: KVM: Correctly handle zero register in system register accesses System register accesses also use zero register for Rt == 31, and therefore using it will also result in getting SP value instead. This patch makes them also using new accessors, introduced by the previous patch. Since register value is no longer directly associated with storage inside vCPU context structure, we introduce a dedicated storage for it in struct sys_reg_params. This refactor also gets rid of "massive hack" in kvm_handle_cp_64(). Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04 15:03:13 +03:00
u64 regval;
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
bool is_write;
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>
2014-01-21 10:55:17 +00:00
bool is_aarch32;
bool is_32bit; /* Only valid if is_aarch32 is true */
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
};
struct sys_reg_desc {
arm64: KVM: Add trapped system register access tracepoint We're pretty blind when it comes to system register tracing, and rely on the ESR value displayed by kvm_handle_sys, which isn't much. Instead, let's add an actual name to the sysreg entries, so that we can finally print it as we're about to perform the access itself. The new tracepoint is conveniently called kvm_sys_access. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-04 10:44:22 +00:00
/* Sysreg string for debug */
const char *name;
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
/* 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 *,
arm64: KVM: Remove const from struct sys_reg_params Further rework is going to introduce a dedicated storage for transfer register value in struct sys_reg_params. Before doing this we have to remove 'const' modifiers from it in all accessor functions and their callers. Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04 15:03:12 +03:00
struct sys_reg_params *,
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
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;
KVM: arm64: introduce vcpu->arch.debug_ptr This introduces a level of indirection for the debug registers. Instead of using the sys_regs[] directly we store registers in a structure in the vcpu. The new kvm_arm_reset_debug_ptr() sets the debug ptr to the guest context. Because we no longer give the sys_regs offset for the sys_reg_desc->reg field, but instead the index into a debug-specific struct we need to add a number of additional trap functions for each register. Also as the generic generic user-space access code no longer works we have introduced a new pair of function pointers to the sys_reg_desc structure to override the generic code when needed. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-07 17:30:00 +01:00
/* 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);
KVM: arm64: Support runtime sysreg visibility filtering Some optional features of the Arm architecture add new system registers that are not present in the base architecture. Where these features are optional for the guest, the visibility of these registers may need to depend on some runtime configuration, such as a flag passed to KVM_ARM_VCPU_INIT. For example, ZCR_EL1 and ID_AA64ZFR0_EL1 need to be hidden if SVE is not enabled for the guest, even though these registers may be present in the hardware and visible to the host at EL2. Adding special-case checks all over the place for individual registers is going to get messy as the number of conditionally- visible registers grows. In order to help solve this problem, this patch adds a new sysreg method visibility() that can be used to hook in any needed runtime visibility checks. This method can currently return REG_HIDDEN_USER to inhibit enumeration and ioctl access to the register for userspace, and REG_HIDDEN_GUEST to inhibit runtime access by the guest using MSR/MRS. Wrappers are added to allow these flags to be conveniently queried. This approach allows a conditionally modified view of individual system registers such as the CPU ID registers, in addition to completely hiding register where appropriate. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 14:39:15 +01:00
/* Return mask of REG_* runtime visibility overrides */
unsigned int (*visibility)(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd);
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
};
KVM: arm64: Support runtime sysreg visibility filtering Some optional features of the Arm architecture add new system registers that are not present in the base architecture. Where these features are optional for the guest, the visibility of these registers may need to depend on some runtime configuration, such as a flag passed to KVM_ARM_VCPU_INIT. For example, ZCR_EL1 and ID_AA64ZFR0_EL1 need to be hidden if SVE is not enabled for the guest, even though these registers may be present in the hardware and visible to the host at EL2. Adding special-case checks all over the place for individual registers is going to get messy as the number of conditionally- visible registers grows. In order to help solve this problem, this patch adds a new sysreg method visibility() that can be used to hook in any needed runtime visibility checks. This method can currently return REG_HIDDEN_USER to inhibit enumeration and ioctl access to the register for userspace, and REG_HIDDEN_GUEST to inhibit runtime access by the guest using MSR/MRS. Wrappers are added to allow these flags to be conveniently queried. This approach allows a conditionally modified view of individual system registers such as the CPU ID registers, in addition to completely hiding register where appropriate. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 14:39:15 +01:00
#define REG_HIDDEN_USER (1 << 0) /* hidden from userspace ioctls */
#define REG_HIDDEN_GUEST (1 << 1) /* hidden from guest */
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
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,
arm64: KVM: Remove const from struct sys_reg_params Further rework is going to introduce a dedicated storage for transfer register value in struct sys_reg_params. Before doing this we have to remove 'const' modifiers from it in all accessor functions and their callers. Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04 15:03:12 +03:00
struct sys_reg_params *p)
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
{
arm64: KVM: Correctly handle zero register in system register accesses System register accesses also use zero register for Rt == 31, and therefore using it will also result in getting SP value instead. This patch makes them also using new accessors, introduced by the previous patch. Since register value is no longer directly associated with storage inside vCPU context structure, we introduce a dedicated storage for it in struct sys_reg_params. This refactor also gets rid of "massive hack" in kvm_handle_cp_64(). Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04 15:03:13 +03:00
p->regval = 0;
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
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);
KVM: arm64: Rewrite system register accessors to read/write functions Currently we access the system registers array via the vcpu_sys_reg() macro. However, we are about to change the behavior to some times modify the register file directly, so let's change this to two primitives: * Accessor macros vcpu_write_sys_reg() and vcpu_read_sys_reg() * Direct array access macro __vcpu_sys_reg() The accessor macros should be used in places where the code needs to access the currently loaded VCPU's state as observed by the guest. For example, when trapping on cache related registers, a write to a system register should go directly to the VCPU version of the register. The direct array access macro can be used in places where the VCPU is known to never be running (for example userspace access) or for registers which are never context switched (for example all the PMU system registers). This rewrites all users of vcpu_sys_regs to one of the macros described above. No functional change. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-16 15:38:53 +01:00
__vcpu_sys_reg(vcpu, r->reg) = 0x1de7ec7edbadc0deULL;
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
}
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);
KVM: arm64: Rewrite system register accessors to read/write functions Currently we access the system registers array via the vcpu_sys_reg() macro. However, we are about to change the behavior to some times modify the register file directly, so let's change this to two primitives: * Accessor macros vcpu_write_sys_reg() and vcpu_read_sys_reg() * Direct array access macro __vcpu_sys_reg() The accessor macros should be used in places where the code needs to access the currently loaded VCPU's state as observed by the guest. For example, when trapping on cache related registers, a write to a system register should go directly to the VCPU version of the register. The direct array access macro can be used in places where the VCPU is known to never be running (for example userspace access) or for registers which are never context switched (for example all the PMU system registers). This rewrites all users of vcpu_sys_regs to one of the macros described above. No functional change. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-16 15:38:53 +01:00
__vcpu_sys_reg(vcpu, r->reg) = r->val;
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
}
KVM: arm64: Support runtime sysreg visibility filtering Some optional features of the Arm architecture add new system registers that are not present in the base architecture. Where these features are optional for the guest, the visibility of these registers may need to depend on some runtime configuration, such as a flag passed to KVM_ARM_VCPU_INIT. For example, ZCR_EL1 and ID_AA64ZFR0_EL1 need to be hidden if SVE is not enabled for the guest, even though these registers may be present in the hardware and visible to the host at EL2. Adding special-case checks all over the place for individual registers is going to get messy as the number of conditionally- visible registers grows. In order to help solve this problem, this patch adds a new sysreg method visibility() that can be used to hook in any needed runtime visibility checks. This method can currently return REG_HIDDEN_USER to inhibit enumeration and ioctl access to the register for userspace, and REG_HIDDEN_GUEST to inhibit runtime access by the guest using MSR/MRS. Wrappers are added to allow these flags to be conveniently queried. This approach allows a conditionally modified view of individual system registers such as the CPU ID registers, in addition to completely hiding register where appropriate. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 14:39:15 +01:00
static inline bool sysreg_hidden_from_guest(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
if (likely(!r->visibility))
return false;
return r->visibility(vcpu, r) & REG_HIDDEN_GUEST;
}
static inline bool sysreg_hidden_from_user(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
if (likely(!r->visibility))
return false;
return r->visibility(vcpu, r) & REG_HIDDEN_USER;
}
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
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;
}
KVM: arm/arm64: vgic: Introduce find_reg_by_id() In order to implement vGICv3 CPU interface access, we will need to perform table lookup of system registers. We would need both index_to_params() and find_reg() exported for that purpose, but instead we export a single function which combines them both. Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-26 19:50:48 +05:30
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);
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
#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
KVM: arm64: add SYS_DESC() This patch adds a macro enabling us to initialise sys_reg_desc structures based on common sysreg encoding definitions in <asm/sysreg.h>. Subsequent patches will use this to simplify the KVM code. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: kvmarm@lists.cs.columbia.edu
2017-01-13 17:25:11 +00:00
#define SYS_DESC(reg) \
arm64: KVM: Add trapped system register access tracepoint We're pretty blind when it comes to system register tracing, and rely on the ESR value displayed by kvm_handle_sys, which isn't much. Instead, let's add an actual name to the sysreg entries, so that we can finally print it as we're about to perform the access itself. The new tracepoint is conveniently called kvm_sys_access. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-04 10:44:22 +00:00
.name = #reg, \
KVM: arm64: add SYS_DESC() This patch adds a macro enabling us to initialise sys_reg_desc structures based on common sysreg encoding definitions in <asm/sysreg.h>. Subsequent patches will use this to simplify the KVM code. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: kvmarm@lists.cs.columbia.edu
2017-01-13 17:25:11 +00:00
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))
arm64: KVM: system register handling Provide 64bit system register handling, modeled after the cp15 handling for ARM. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 16:15:34 +00:00
#endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */
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