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linux-stable/arch/arm/kvm/coproc.c
Christoffer Dall 1138245ccf KVM: ARM: User space API for getting/setting co-proc registers 
The following three ioctls are implemented:
 -  KVM_GET_REG_LIST
 -  KVM_GET_ONE_REG
 -  KVM_SET_ONE_REG

Now we have a table for all the cp15 registers, we can drive a generic
API.

The register IDs carry the following encoding:

ARM registers are mapped using the lower 32 bits.  The upper 16 of that
is the register group type, or coprocessor number:

ARM 32-bit CP15 registers have the following id bit patterns:
  0x4002 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>

ARM 64-bit CP15 registers have the following id bit patterns:
  0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>

For futureproofing, we need to tell QEMU about the CP15 registers the
host lets the guest access.

It will need this information to restore a current guest on a future
CPU or perhaps a future KVM which allow some of these to be changed.

We use a separate table for these, as they're only for the userspace API.

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 13:29:14 -05:00

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/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Authors: Rusty Russell <rusty@rustcorp.com.au>
* 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.
*/
#include <linux/mm.h>
#include <linux/kvm_host.h>
#include <linux/uaccess.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_host.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_coproc.h>
#include <asm/cacheflush.h>
#include <asm/cputype.h>
#include <trace/events/kvm.h>
#include "trace.h"
#include "coproc.h"
/******************************************************************************
* Co-processor emulation
*****************************************************************************/
int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
kvm_inject_undefined(vcpu);
return 1;
}
int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
/*
* We can get here, if the host has been built without VFPv3 support,
* but the guest attempted a floating point operation.
*/
kvm_inject_undefined(vcpu);
return 1;
}
int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
kvm_inject_undefined(vcpu);
return 1;
}
int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
kvm_inject_undefined(vcpu);
return 1;
}
/* See note at ARM ARM B1.14.4 */
static bool access_dcsw(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
u32 val;
int cpu;
cpu = get_cpu();
if (!p->is_write)
return read_from_write_only(vcpu, p);
cpumask_setall(&vcpu->arch.require_dcache_flush);
cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);
/* If we were already preempted, take the long way around */
if (cpu != vcpu->arch.last_pcpu) {
flush_cache_all();
goto done;
}
val = *vcpu_reg(vcpu, p->Rt1);
switch (p->CRm) {
case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */
case 14: /* DCCISW */
asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val));
break;
case 10: /* DCCSW */
asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val));
break;
}
done:
put_cpu();
return true;
}
/*
* We could trap ID_DFR0 and tell the guest we don't support performance
* monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was
* NAKed, so it will read the PMCR anyway.
*
* Therefore we tell the guest we have 0 counters. Unfortunately, we
* must always support PMCCNTR (the cycle counter): we just RAZ/WI for
* all PM registers, which doesn't crash the guest kernel at least.
*/
static bool pm_fake(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
if (p->is_write)
return ignore_write(vcpu, p);
else
return read_zero(vcpu, p);
}
#define access_pmcr pm_fake
#define access_pmcntenset pm_fake
#define access_pmcntenclr pm_fake
#define access_pmovsr pm_fake
#define access_pmselr pm_fake
#define access_pmceid0 pm_fake
#define access_pmceid1 pm_fake
#define access_pmccntr pm_fake
#define access_pmxevtyper pm_fake
#define access_pmxevcntr pm_fake
#define access_pmuserenr pm_fake
#define access_pmintenset pm_fake
#define access_pmintenclr pm_fake
/* Architected CP15 registers.
* Important: Must be sorted ascending by CRn, CRM, Op1, Op2
*/
static const struct coproc_reg cp15_regs[] = {
/* CSSELR: swapped by interrupt.S. */
{ CRn( 0), CRm( 0), Op1( 2), Op2( 0), is32,
NULL, reset_unknown, c0_CSSELR },
/* TTBR0/TTBR1: swapped by interrupt.S. */
{ CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
{ CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
/* TTBCR: swapped by interrupt.S. */
{ CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32,
NULL, reset_val, c2_TTBCR, 0x00000000 },
/* DACR: swapped by interrupt.S. */
{ CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32,
NULL, reset_unknown, c3_DACR },
/* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */
{ CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32,
NULL, reset_unknown, c5_DFSR },
{ CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32,
NULL, reset_unknown, c5_IFSR },
{ CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32,
NULL, reset_unknown, c5_ADFSR },
{ CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32,
NULL, reset_unknown, c5_AIFSR },
/* DFAR/IFAR: swapped by interrupt.S. */
{ CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32,
NULL, reset_unknown, c6_DFAR },
{ CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32,
NULL, reset_unknown, c6_IFAR },
/*
* DC{C,I,CI}SW operations:
*/
{ CRn( 7), CRm( 6), Op1( 0), Op2( 2), is32, access_dcsw},
{ CRn( 7), CRm(10), Op1( 0), Op2( 2), is32, access_dcsw},
{ CRn( 7), CRm(14), Op1( 0), Op2( 2), is32, access_dcsw},
/*
* Dummy performance monitor implementation.
*/
{ CRn( 9), CRm(12), Op1( 0), Op2( 0), is32, access_pmcr},
{ CRn( 9), CRm(12), Op1( 0), Op2( 1), is32, access_pmcntenset},
{ CRn( 9), CRm(12), Op1( 0), Op2( 2), is32, access_pmcntenclr},
{ CRn( 9), CRm(12), Op1( 0), Op2( 3), is32, access_pmovsr},
{ CRn( 9), CRm(12), Op1( 0), Op2( 5), is32, access_pmselr},
{ CRn( 9), CRm(12), Op1( 0), Op2( 6), is32, access_pmceid0},
{ CRn( 9), CRm(12), Op1( 0), Op2( 7), is32, access_pmceid1},
{ CRn( 9), CRm(13), Op1( 0), Op2( 0), is32, access_pmccntr},
{ CRn( 9), CRm(13), Op1( 0), Op2( 1), is32, access_pmxevtyper},
{ CRn( 9), CRm(13), Op1( 0), Op2( 2), is32, access_pmxevcntr},
{ CRn( 9), CRm(14), Op1( 0), Op2( 0), is32, access_pmuserenr},
{ CRn( 9), CRm(14), Op1( 0), Op2( 1), is32, access_pmintenset},
{ CRn( 9), CRm(14), Op1( 0), Op2( 2), is32, access_pmintenclr},
/* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */
{ CRn(10), CRm( 2), Op1( 0), Op2( 0), is32,
NULL, reset_unknown, c10_PRRR},
{ CRn(10), CRm( 2), Op1( 0), Op2( 1), is32,
NULL, reset_unknown, c10_NMRR},
/* VBAR: swapped by interrupt.S. */
{ CRn(12), CRm( 0), Op1( 0), Op2( 0), is32,
NULL, reset_val, c12_VBAR, 0x00000000 },
/* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */
{ CRn(13), CRm( 0), Op1( 0), Op2( 1), is32,
NULL, reset_val, c13_CID, 0x00000000 },
{ CRn(13), CRm( 0), Op1( 0), Op2( 2), is32,
NULL, reset_unknown, c13_TID_URW },
{ CRn(13), CRm( 0), Op1( 0), Op2( 3), is32,
NULL, reset_unknown, c13_TID_URO },
{ CRn(13), CRm( 0), Op1( 0), Op2( 4), is32,
NULL, reset_unknown, c13_TID_PRIV },
};
/* Target specific emulation tables */
static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS];
void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table)
{
target_tables[table->target] = table;
}
/* Get specific register table for this target. */
static const struct coproc_reg *get_target_table(unsigned target, size_t *num)
{
struct kvm_coproc_target_table *table;
table = target_tables[target];
*num = table->num;
return table->table;
}
static const struct coproc_reg *find_reg(const struct coproc_params *params,
const struct coproc_reg table[],
unsigned int num)
{
unsigned int i;
for (i = 0; i < num; i++) {
const struct coproc_reg *r = &table[i];
if (params->is_64bit != r->is_64)
continue;
if (params->CRn != r->CRn)
continue;
if (params->CRm != r->CRm)
continue;
if (params->Op1 != r->Op1)
continue;
if (params->Op2 != r->Op2)
continue;
return r;
}
return NULL;
}
static int emulate_cp15(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
size_t num;
const struct coproc_reg *table, *r;
trace_kvm_emulate_cp15_imp(params->Op1, params->Rt1, params->CRn,
params->CRm, params->Op2, params->is_write);
table = get_target_table(vcpu->arch.target, &num);
/* Search target-specific then generic table. */
r = find_reg(params, table, num);
if (!r)
r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs));
if (likely(r)) {
/* If we don't have an accessor, we should never get here! */
BUG_ON(!r->access);
if (likely(r->access(vcpu, params, r))) {
/* Skip instruction, since it was emulated */
kvm_skip_instr(vcpu, (vcpu->arch.hsr >> 25) & 1);
return 1;
}
/* If access function fails, it should complain. */
} else {
kvm_err("Unsupported guest CP15 access at: %08x\n",
*vcpu_pc(vcpu));
print_cp_instr(params);
}
kvm_inject_undefined(vcpu);
return 1;
}
/**
* kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access
* @vcpu: The VCPU pointer
* @run: The kvm_run struct
*/
int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
struct coproc_params params;
params.CRm = (vcpu->arch.hsr >> 1) & 0xf;
params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf;
params.is_write = ((vcpu->arch.hsr & 1) == 0);
params.is_64bit = true;
params.Op1 = (vcpu->arch.hsr >> 16) & 0xf;
params.Op2 = 0;
params.Rt2 = (vcpu->arch.hsr >> 10) & 0xf;
params.CRn = 0;
return emulate_cp15(vcpu, &params);
}
static void reset_coproc_regs(struct kvm_vcpu *vcpu,
const struct coproc_reg *table, size_t num)
{
unsigned long i;
for (i = 0; i < num; i++)
if (table[i].reset)
table[i].reset(vcpu, &table[i]);
}
/**
* kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
* @vcpu: The VCPU pointer
* @run: The kvm_run struct
*/
int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
struct coproc_params params;
params.CRm = (vcpu->arch.hsr >> 1) & 0xf;
params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf;
params.is_write = ((vcpu->arch.hsr & 1) == 0);
params.is_64bit = false;
params.CRn = (vcpu->arch.hsr >> 10) & 0xf;
params.Op1 = (vcpu->arch.hsr >> 14) & 0x7;
params.Op2 = (vcpu->arch.hsr >> 17) & 0x7;
params.Rt2 = 0;
return emulate_cp15(vcpu, &params);
}
/******************************************************************************
* Userspace API
*****************************************************************************/
static bool index_to_params(u64 id, struct coproc_params *params)
{
switch (id & KVM_REG_SIZE_MASK) {
case KVM_REG_SIZE_U32:
/* Any unused index bits means it's not valid. */
if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
| KVM_REG_ARM_COPROC_MASK
| KVM_REG_ARM_32_CRN_MASK
| KVM_REG_ARM_CRM_MASK
| KVM_REG_ARM_OPC1_MASK
| KVM_REG_ARM_32_OPC2_MASK))
return false;
params->is_64bit = false;
params->CRn = ((id & KVM_REG_ARM_32_CRN_MASK)
>> KVM_REG_ARM_32_CRN_SHIFT);
params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
>> KVM_REG_ARM_CRM_SHIFT);
params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
>> KVM_REG_ARM_OPC1_SHIFT);
params->Op2 = ((id & KVM_REG_ARM_32_OPC2_MASK)
>> KVM_REG_ARM_32_OPC2_SHIFT);
return true;
case KVM_REG_SIZE_U64:
/* Any unused index bits means it's not valid. */
if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
| KVM_REG_ARM_COPROC_MASK
| KVM_REG_ARM_CRM_MASK
| KVM_REG_ARM_OPC1_MASK))
return false;
params->is_64bit = true;
params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
>> KVM_REG_ARM_CRM_SHIFT);
params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
>> KVM_REG_ARM_OPC1_SHIFT);
params->Op2 = 0;
params->CRn = 0;
return true;
default:
return false;
}
}
/* Decode an index value, and find the cp15 coproc_reg entry. */
static const struct coproc_reg *index_to_coproc_reg(struct kvm_vcpu *vcpu,
u64 id)
{
size_t num;
const struct coproc_reg *table, *r;
struct coproc_params params;
/* We only do cp15 for now. */
if ((id & KVM_REG_ARM_COPROC_MASK) >> KVM_REG_ARM_COPROC_SHIFT != 15)
return NULL;
if (!index_to_params(id, &params))
return NULL;
table = get_target_table(vcpu->arch.target, &num);
r = find_reg(&params, table, num);
if (!r)
r = find_reg(&params, cp15_regs, ARRAY_SIZE(cp15_regs));
/* Not saved in the cp15 array? */
if (r && !r->reg)
r = NULL;
return r;
}
/*
* These are the invariant cp15 registers: we let the guest see the host
* versions of these, so they're part of the guest state.
*
* A future CPU may provide a mechanism to present different values to
* the guest, or a future kvm may trap them.
*/
/* Unfortunately, there's no register-argument for mrc, so generate. */
#define FUNCTION_FOR32(crn, crm, op1, op2, name) \
static void get_##name(struct kvm_vcpu *v, \
const struct coproc_reg *r) \
{ \
u32 val; \
\
asm volatile("mrc p15, " __stringify(op1) \
", %0, c" __stringify(crn) \
", c" __stringify(crm) \
", " __stringify(op2) "\n" : "=r" (val)); \
((struct coproc_reg *)r)->val = val; \
}
FUNCTION_FOR32(0, 0, 0, 0, MIDR)
FUNCTION_FOR32(0, 0, 0, 1, CTR)
FUNCTION_FOR32(0, 0, 0, 2, TCMTR)
FUNCTION_FOR32(0, 0, 0, 3, TLBTR)
FUNCTION_FOR32(0, 0, 0, 6, REVIDR)
FUNCTION_FOR32(0, 1, 0, 0, ID_PFR0)
FUNCTION_FOR32(0, 1, 0, 1, ID_PFR1)
FUNCTION_FOR32(0, 1, 0, 2, ID_DFR0)
FUNCTION_FOR32(0, 1, 0, 3, ID_AFR0)
FUNCTION_FOR32(0, 1, 0, 4, ID_MMFR0)
FUNCTION_FOR32(0, 1, 0, 5, ID_MMFR1)
FUNCTION_FOR32(0, 1, 0, 6, ID_MMFR2)
FUNCTION_FOR32(0, 1, 0, 7, ID_MMFR3)
FUNCTION_FOR32(0, 2, 0, 0, ID_ISAR0)
FUNCTION_FOR32(0, 2, 0, 1, ID_ISAR1)
FUNCTION_FOR32(0, 2, 0, 2, ID_ISAR2)
FUNCTION_FOR32(0, 2, 0, 3, ID_ISAR3)
FUNCTION_FOR32(0, 2, 0, 4, ID_ISAR4)
FUNCTION_FOR32(0, 2, 0, 5, ID_ISAR5)
FUNCTION_FOR32(0, 0, 1, 1, CLIDR)
FUNCTION_FOR32(0, 0, 1, 7, AIDR)
/* ->val is filled in by kvm_invariant_coproc_table_init() */
static struct coproc_reg invariant_cp15[] = {
{ CRn( 0), CRm( 0), Op1( 0), Op2( 0), is32, NULL, get_MIDR },
{ CRn( 0), CRm( 0), Op1( 0), Op2( 1), is32, NULL, get_CTR },
{ CRn( 0), CRm( 0), Op1( 0), Op2( 2), is32, NULL, get_TCMTR },
{ CRn( 0), CRm( 0), Op1( 0), Op2( 3), is32, NULL, get_TLBTR },
{ CRn( 0), CRm( 0), Op1( 0), Op2( 6), is32, NULL, get_REVIDR },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 0), is32, NULL, get_ID_PFR0 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 1), is32, NULL, get_ID_PFR1 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 2), is32, NULL, get_ID_DFR0 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 3), is32, NULL, get_ID_AFR0 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 4), is32, NULL, get_ID_MMFR0 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 5), is32, NULL, get_ID_MMFR1 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 6), is32, NULL, get_ID_MMFR2 },
{ CRn( 0), CRm( 1), Op1( 0), Op2( 7), is32, NULL, get_ID_MMFR3 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 0), is32, NULL, get_ID_ISAR0 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 1), is32, NULL, get_ID_ISAR1 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 2), is32, NULL, get_ID_ISAR2 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 3), is32, NULL, get_ID_ISAR3 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 4), is32, NULL, get_ID_ISAR4 },
{ CRn( 0), CRm( 2), Op1( 0), Op2( 5), is32, NULL, get_ID_ISAR5 },
{ CRn( 0), CRm( 0), Op1( 1), Op2( 1), is32, NULL, get_CLIDR },
{ CRn( 0), CRm( 0), Op1( 1), Op2( 7), is32, NULL, get_AIDR },
};
static int reg_from_user(void *val, const void __user *uaddr, u64 id)
{
/* This Just Works because we are little endian. */
if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
return -EFAULT;
return 0;
}
static int reg_to_user(void __user *uaddr, const void *val, u64 id)
{
/* This Just Works because we are little endian. */
if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
return -EFAULT;
return 0;
}
static int get_invariant_cp15(u64 id, void __user *uaddr)
{
struct coproc_params params;
const struct coproc_reg *r;
if (!index_to_params(id, &params))
return -ENOENT;
r = find_reg(&params, invariant_cp15, ARRAY_SIZE(invariant_cp15));
if (!r)
return -ENOENT;
return reg_to_user(uaddr, &r->val, id);
}
static int set_invariant_cp15(u64 id, void __user *uaddr)
{
struct coproc_params params;
const struct coproc_reg *r;
int err;
u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */
if (!index_to_params(id, &params))
return -ENOENT;
r = find_reg(&params, invariant_cp15, ARRAY_SIZE(invariant_cp15));
if (!r)
return -ENOENT;
err = reg_from_user(&val, uaddr, id);
if (err)
return err;
/* This is what we mean by invariant: you can't change it. */
if (r->val != val)
return -EINVAL;
return 0;
}
int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return get_invariant_cp15(reg->id, uaddr);
/* Note: copies two regs if size is 64 bit. */
return reg_to_user(uaddr, &vcpu->arch.cp15[r->reg], reg->id);
}
int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return set_invariant_cp15(reg->id, uaddr);
/* Note: copies two regs if size is 64 bit */
return reg_from_user(&vcpu->arch.cp15[r->reg], uaddr, reg->id);
}
static u64 cp15_to_index(const struct coproc_reg *reg)
{
u64 val = KVM_REG_ARM | (15 << KVM_REG_ARM_COPROC_SHIFT);
if (reg->is_64) {
val |= KVM_REG_SIZE_U64;
val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
} else {
val |= KVM_REG_SIZE_U32;
val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
val |= (reg->Op2 << KVM_REG_ARM_32_OPC2_SHIFT);
val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
val |= (reg->CRn << KVM_REG_ARM_32_CRN_SHIFT);
}
return val;
}
static bool copy_reg_to_user(const struct coproc_reg *reg, u64 __user **uind)
{
if (!*uind)
return true;
if (put_user(cp15_to_index(reg), *uind))
return false;
(*uind)++;
return true;
}
/* Assumed ordered tables, see kvm_coproc_table_init. */
static int walk_cp15(struct kvm_vcpu *vcpu, u64 __user *uind)
{
const struct coproc_reg *i1, *i2, *end1, *end2;
unsigned int total = 0;
size_t num;
/* We check for duplicates here, to allow arch-specific overrides. */
i1 = get_target_table(vcpu->arch.target, &num);
end1 = i1 + num;
i2 = cp15_regs;
end2 = cp15_regs + ARRAY_SIZE(cp15_regs);
BUG_ON(i1 == end1 || i2 == end2);
/* Walk carefully, as both tables may refer to the same register. */
while (i1 || i2) {
int cmp = cmp_reg(i1, i2);
/* target-specific overrides generic entry. */
if (cmp <= 0) {
/* Ignore registers we trap but don't save. */
if (i1->reg) {
if (!copy_reg_to_user(i1, &uind))
return -EFAULT;
total++;
}
} else {
/* Ignore registers we trap but don't save. */
if (i2->reg) {
if (!copy_reg_to_user(i2, &uind))
return -EFAULT;
total++;
}
}
if (cmp <= 0 && ++i1 == end1)
i1 = NULL;
if (cmp >= 0 && ++i2 == end2)
i2 = NULL;
}
return total;
}
unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
{
return ARRAY_SIZE(invariant_cp15)
+ walk_cp15(vcpu, (u64 __user *)NULL);
}
int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
unsigned int i;
int err;
/* Then give them all the invariant registers' indices. */
for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++) {
if (put_user(cp15_to_index(&invariant_cp15[i]), uindices))
return -EFAULT;
uindices++;
}
err = walk_cp15(vcpu, uindices);
if (err > 0)
err = 0;
return err;
}
void kvm_coproc_table_init(void)
{
unsigned int i;
/* Make sure tables are unique and in order. */
for (i = 1; i < ARRAY_SIZE(cp15_regs); i++)
BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0);
/* We abuse the reset function to overwrite the table itself. */
for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++)
invariant_cp15[i].reset(NULL, &invariant_cp15[i]);
}
/**
* kvm_reset_coprocs - sets cp15 registers to reset value
* @vcpu: The VCPU pointer
*
* This function finds the right table above and sets the registers on the
* virtual CPU struct to their architecturally defined reset values.
*/
void kvm_reset_coprocs(struct kvm_vcpu *vcpu)
{
size_t num;
const struct coproc_reg *table;
/* Catch someone adding a register without putting in reset entry. */
memset(vcpu->arch.cp15, 0x42, sizeof(vcpu->arch.cp15));
/* Generic chip reset first (so target could override). */
reset_coproc_regs(vcpu, cp15_regs, ARRAY_SIZE(cp15_regs));
table = get_target_table(vcpu->arch.target, &num);
reset_coproc_regs(vcpu, table, num);
for (num = 1; num < NR_CP15_REGS; num++)
if (vcpu->arch.cp15[num] == 0x42424242)
panic("Didn't reset vcpu->arch.cp15[%zi]", num);
}
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