linux/arch/powerpc/kvm/emulate_loadstore.c
Jordan Niethe 52425a3b3c KVM: PPC: Introduce FPR/VR accessor functions
Introduce accessor functions for floating point and vector registers
like the ones that exist for GPRs. Use these to replace the existing FPR
and VR accessor macros.

This will be important later for Nested APIv2 support which requires
additional functionality for accessing and modifying VCPU state.

Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230914030600.16993-3-jniethe5@gmail.com
2023-09-14 22:04:23 +10:00

367 lines
9.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright IBM Corp. 2007
* Copyright 2011 Freescale Semiconductor, Inc.
*
* Authors: Hollis Blanchard <hollisb@us.ibm.com>
*/
#include <linux/jiffies.h>
#include <linux/hrtimer.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm_host.h>
#include <linux/clockchips.h>
#include <asm/reg.h>
#include <asm/time.h>
#include <asm/byteorder.h>
#include <asm/kvm_ppc.h>
#include <asm/disassemble.h>
#include <asm/ppc-opcode.h>
#include <asm/sstep.h>
#include "timing.h"
#include "trace.h"
#ifdef CONFIG_PPC_FPU
static bool kvmppc_check_fp_disabled(struct kvm_vcpu *vcpu)
{
if (!(kvmppc_get_msr(vcpu) & MSR_FP)) {
kvmppc_core_queue_fpunavail(vcpu, kvmppc_get_msr(vcpu) & SRR1_PREFIXED);
return true;
}
return false;
}
#endif /* CONFIG_PPC_FPU */
#ifdef CONFIG_VSX
static bool kvmppc_check_vsx_disabled(struct kvm_vcpu *vcpu)
{
if (!(kvmppc_get_msr(vcpu) & MSR_VSX)) {
kvmppc_core_queue_vsx_unavail(vcpu, kvmppc_get_msr(vcpu) & SRR1_PREFIXED);
return true;
}
return false;
}
#endif /* CONFIG_VSX */
#ifdef CONFIG_ALTIVEC
static bool kvmppc_check_altivec_disabled(struct kvm_vcpu *vcpu)
{
if (!(kvmppc_get_msr(vcpu) & MSR_VEC)) {
kvmppc_core_queue_vec_unavail(vcpu, kvmppc_get_msr(vcpu) & SRR1_PREFIXED);
return true;
}
return false;
}
#endif /* CONFIG_ALTIVEC */
/*
* XXX to do:
* lfiwax, lfiwzx
* vector loads and stores
*
* Instructions that trap when used on cache-inhibited mappings
* are not emulated here: multiple and string instructions,
* lq/stq, and the load-reserve/store-conditional instructions.
*/
int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
{
ppc_inst_t inst;
enum emulation_result emulated = EMULATE_FAIL;
struct instruction_op op;
/* this default type might be overwritten by subcategories */
kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS);
emulated = kvmppc_get_last_inst(vcpu, INST_GENERIC, &inst);
if (emulated != EMULATE_DONE)
return emulated;
vcpu->arch.mmio_vsx_copy_nums = 0;
vcpu->arch.mmio_vsx_offset = 0;
vcpu->arch.mmio_copy_type = KVMPPC_VSX_COPY_NONE;
vcpu->arch.mmio_sp64_extend = 0;
vcpu->arch.mmio_sign_extend = 0;
vcpu->arch.mmio_vmx_copy_nums = 0;
vcpu->arch.mmio_vmx_offset = 0;
vcpu->arch.mmio_host_swabbed = 0;
emulated = EMULATE_FAIL;
vcpu->arch.regs.msr = vcpu->arch.shared->msr;
if (analyse_instr(&op, &vcpu->arch.regs, inst) == 0) {
int type = op.type & INSTR_TYPE_MASK;
int size = GETSIZE(op.type);
vcpu->mmio_is_write = OP_IS_STORE(type);
switch (type) {
case LOAD: {
int instr_byte_swap = op.type & BYTEREV;
if (op.type & SIGNEXT)
emulated = kvmppc_handle_loads(vcpu,
op.reg, size, !instr_byte_swap);
else
emulated = kvmppc_handle_load(vcpu,
op.reg, size, !instr_byte_swap);
if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
break;
}
#ifdef CONFIG_PPC_FPU
case LOAD_FP:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
if (op.type & FPCONV)
vcpu->arch.mmio_sp64_extend = 1;
if (op.type & SIGNEXT)
emulated = kvmppc_handle_loads(vcpu,
KVM_MMIO_REG_FPR|op.reg, size, 1);
else
emulated = kvmppc_handle_load(vcpu,
KVM_MMIO_REG_FPR|op.reg, size, 1);
if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
break;
#endif
#ifdef CONFIG_ALTIVEC
case LOAD_VMX:
if (kvmppc_check_altivec_disabled(vcpu))
return EMULATE_DONE;
/* Hardware enforces alignment of VMX accesses */
vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);
if (size == 16) { /* lvx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_DWORD;
} else if (size == 4) { /* lvewx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_WORD;
} else if (size == 2) { /* lvehx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_HWORD;
} else if (size == 1) { /* lvebx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_BYTE;
} else
break;
vcpu->arch.mmio_vmx_offset =
(vcpu->arch.vaddr_accessed & 0xf)/size;
if (size == 16) {
vcpu->arch.mmio_vmx_copy_nums = 2;
emulated = kvmppc_handle_vmx_load(vcpu,
KVM_MMIO_REG_VMX|op.reg,
8, 1);
} else {
vcpu->arch.mmio_vmx_copy_nums = 1;
emulated = kvmppc_handle_vmx_load(vcpu,
KVM_MMIO_REG_VMX|op.reg,
size, 1);
}
break;
#endif
#ifdef CONFIG_VSX
case LOAD_VSX: {
int io_size_each;
if (op.vsx_flags & VSX_CHECK_VEC) {
if (kvmppc_check_altivec_disabled(vcpu))
return EMULATE_DONE;
} else {
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
}
if (op.vsx_flags & VSX_FPCONV)
vcpu->arch.mmio_sp64_extend = 1;
if (op.element_size == 8) {
if (op.vsx_flags & VSX_SPLAT)
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_DWORD_LOAD_DUMP;
else
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_DWORD;
} else if (op.element_size == 4) {
if (op.vsx_flags & VSX_SPLAT)
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_WORD_LOAD_DUMP;
else
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_WORD;
} else
break;
if (size < op.element_size) {
/* precision convert case: lxsspx, etc */
vcpu->arch.mmio_vsx_copy_nums = 1;
io_size_each = size;
} else { /* lxvw4x, lxvd2x, etc */
vcpu->arch.mmio_vsx_copy_nums =
size/op.element_size;
io_size_each = op.element_size;
}
emulated = kvmppc_handle_vsx_load(vcpu,
KVM_MMIO_REG_VSX|op.reg, io_size_each,
1, op.type & SIGNEXT);
break;
}
#endif
case STORE:
/* if need byte reverse, op.val has been reversed by
* analyse_instr().
*/
emulated = kvmppc_handle_store(vcpu, op.val, size, 1);
if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
break;
#ifdef CONFIG_PPC_FPU
case STORE_FP:
if (kvmppc_check_fp_disabled(vcpu))
return EMULATE_DONE;
/* The FP registers need to be flushed so that
* kvmppc_handle_store() can read actual FP vals
* from vcpu->arch.
*/
if (vcpu->kvm->arch.kvm_ops->giveup_ext)
vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
MSR_FP);
if (op.type & FPCONV)
vcpu->arch.mmio_sp64_extend = 1;
emulated = kvmppc_handle_store(vcpu,
kvmppc_get_fpr(vcpu, op.reg), size, 1);
if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
break;
#endif
#ifdef CONFIG_ALTIVEC
case STORE_VMX:
if (kvmppc_check_altivec_disabled(vcpu))
return EMULATE_DONE;
/* Hardware enforces alignment of VMX accesses. */
vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);
if (vcpu->kvm->arch.kvm_ops->giveup_ext)
vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
MSR_VEC);
if (size == 16) { /* stvx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_DWORD;
} else if (size == 4) { /* stvewx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_WORD;
} else if (size == 2) { /* stvehx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_HWORD;
} else if (size == 1) { /* stvebx */
vcpu->arch.mmio_copy_type =
KVMPPC_VMX_COPY_BYTE;
} else
break;
vcpu->arch.mmio_vmx_offset =
(vcpu->arch.vaddr_accessed & 0xf)/size;
if (size == 16) {
vcpu->arch.mmio_vmx_copy_nums = 2;
emulated = kvmppc_handle_vmx_store(vcpu,
op.reg, 8, 1);
} else {
vcpu->arch.mmio_vmx_copy_nums = 1;
emulated = kvmppc_handle_vmx_store(vcpu,
op.reg, size, 1);
}
break;
#endif
#ifdef CONFIG_VSX
case STORE_VSX: {
int io_size_each;
if (op.vsx_flags & VSX_CHECK_VEC) {
if (kvmppc_check_altivec_disabled(vcpu))
return EMULATE_DONE;
} else {
if (kvmppc_check_vsx_disabled(vcpu))
return EMULATE_DONE;
}
if (vcpu->kvm->arch.kvm_ops->giveup_ext)
vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
MSR_VSX);
if (op.vsx_flags & VSX_FPCONV)
vcpu->arch.mmio_sp64_extend = 1;
if (op.element_size == 8)
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_DWORD;
else if (op.element_size == 4)
vcpu->arch.mmio_copy_type =
KVMPPC_VSX_COPY_WORD;
else
break;
if (size < op.element_size) {
/* precise conversion case, like stxsspx */
vcpu->arch.mmio_vsx_copy_nums = 1;
io_size_each = size;
} else { /* stxvw4x, stxvd2x, etc */
vcpu->arch.mmio_vsx_copy_nums =
size/op.element_size;
io_size_each = op.element_size;
}
emulated = kvmppc_handle_vsx_store(vcpu,
op.reg, io_size_each, 1);
break;
}
#endif
case CACHEOP:
/* Do nothing. The guest is performing dcbi because
* hardware DMA is not snooped by the dcache, but
* emulated DMA either goes through the dcache as
* normal writes, or the host kernel has handled dcache
* coherence.
*/
emulated = EMULATE_DONE;
break;
default:
break;
}
}
trace_kvm_ppc_instr(ppc_inst_val(inst), kvmppc_get_pc(vcpu), emulated);
/* Advance past emulated instruction. */
if (emulated != EMULATE_FAIL)
kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + ppc_inst_len(inst));
return emulated;
}