Refactor MIPS KVM MMIO load/store emulation to reduce code duplication.
Each duplicate differed slightly anyway, and it will simplify adding
64-bit MMIO support for VZ.
kvm_mips_emulate_store() and kvm_mips_emulate_load() can now return
EMULATE_DO_MMIO (as possibly originally intended). We therefore stop
calling either of these from kvm_mips_emulate_inst(), which is now only
used by kvm_trap_emul_handle_cop_unusable() which is picky about return
values.
Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: "Radim Krčmář" <rkrcmar@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
---
arch/mips/kvm/emulate.c | 206 +++++++++--------------------------------
1 file changed, 50 insertions(+), 156 deletions(-)
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index 637753ea0a00..e0f74ee2aad8 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -1477,9 +1477,8 @@ enum emulation_result kvm_mips_emulate_store(union mips_instruction inst,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
- enum emulation_result er = EMULATE_DO_MMIO;
+ enum emulation_result er;
u32 rt;
- u32 bytes;
void *data = run->mmio.data;
unsigned long curr_pc;
@@ -1494,103 +1493,63 @@ enum emulation_result kvm_mips_emulate_store(union mips_instruction inst,
rt = inst.i_format.rt;
- switch (inst.i_format.opcode) {
- case sb_op:
- bytes = 1;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
- run->mmio.len = bytes;
- run->mmio.is_write = 1;
- vcpu->mmio_needed = 1;
- vcpu->mmio_is_write = 1;
- *(u8 *) data = vcpu->arch.gprs[rt];
- kvm_debug("OP_SB: eaddr: %#lx, gpr: %#lx, data: %#x\n",
- vcpu->arch.host_cp0_badvaddr, vcpu->arch.gprs[rt],
- *(u8 *) data);
-
- break;
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr);
+ if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+ goto out_fail;
+ switch (inst.i_format.opcode) {
case sw_op:
- bytes = 4;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
-
- run->mmio.len = bytes;
- run->mmio.is_write = 1;
- vcpu->mmio_needed = 1;
- vcpu->mmio_is_write = 1;
- *(u32 *) data = vcpu->arch.gprs[rt];
+ run->mmio.len = 4;
+ *(u32 *)data = vcpu->arch.gprs[rt];
kvm_debug("[%#lx] OP_SW: eaddr: %#lx, gpr: %#lx, data: %#x\n",
vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
- vcpu->arch.gprs[rt], *(u32 *) data);
+ vcpu->arch.gprs[rt], *(u32 *)data);
break;
case sh_op:
- bytes = 2;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
-
- run->mmio.len = bytes;
- run->mmio.is_write = 1;
- vcpu->mmio_needed = 1;
- vcpu->mmio_is_write = 1;
- *(u16 *) data = vcpu->arch.gprs[rt];
+ run->mmio.len = 2;
+ *(u16 *)data = vcpu->arch.gprs[rt];
kvm_debug("[%#lx] OP_SH: eaddr: %#lx, gpr: %#lx, data: %#x\n",
vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
- vcpu->arch.gprs[rt], *(u32 *) data);
+ vcpu->arch.gprs[rt], *(u16 *)data);
+ break;
+
+ case sb_op:
+ run->mmio.len = 1;
+ *(u8 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_SB: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u8 *)data);
break;
default:
kvm_err("Store not yet supported (inst=0x%08x)\n",
inst.word);
- er = EMULATE_FAIL;
- break;
+ goto out_fail;
}
- /* Rollback PC if emulation was unsuccessful */
- if (er == EMULATE_FAIL)
- vcpu->arch.pc = curr_pc;
+ run->mmio.is_write = 1;
+ vcpu->mmio_needed = 1;
+ vcpu->mmio_is_write = 1;
+ return EMULATE_DO_MMIO;
- return er;
+out_fail:
+ /* Rollback PC if emulation was unsuccessful */
+ vcpu->arch.pc = curr_pc;
+ return EMULATE_FAIL;
}
enum emulation_result kvm_mips_emulate_load(union mips_instruction inst,
u32 cause, struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
- enum emulation_result er = EMULATE_DO_MMIO;
+ enum emulation_result er;
unsigned long curr_pc;
u32 op, rt;
- u32 bytes;
rt = inst.i_format.rt;
op = inst.i_format.opcode;
@@ -1609,94 +1568,41 @@ enum emulation_result kvm_mips_emulate_load(union mips_instruction inst,
vcpu->arch.io_gpr = rt;
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr);
+ if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+ return EMULATE_FAIL;
+
+ vcpu->mmio_needed = 2; /* signed */
switch (op) {
case lw_op:
- bytes = 4;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- er = EMULATE_FAIL;
- break;
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
-
- run->mmio.len = bytes;
- run->mmio.is_write = 0;
- vcpu->mmio_needed = 1;
- vcpu->mmio_is_write = 0;
+ run->mmio.len = 4;
break;
- case lh_op:
case lhu_op:
- bytes = 2;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- er = EMULATE_FAIL;
- break;
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
-
- run->mmio.len = bytes;
- run->mmio.is_write = 0;
- vcpu->mmio_needed = 1;
- vcpu->mmio_is_write = 0;
-
- if (op == lh_op)
- vcpu->mmio_needed = 2;
- else
- vcpu->mmio_needed = 1;
-
+ vcpu->mmio_needed = 1; /* unsigned */
+ /* fall through */
+ case lh_op:
+ run->mmio.len = 2;
break;
case lbu_op:
+ vcpu->mmio_needed = 1; /* unsigned */
+ /* fall through */
case lb_op:
- bytes = 1;
- if (bytes > sizeof(run->mmio.data)) {
- kvm_err("%s: bad MMIO length: %d\n", __func__,
- run->mmio.len);
- er = EMULATE_FAIL;
- break;
- }
- run->mmio.phys_addr =
- kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
- host_cp0_badvaddr);
- if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
- er = EMULATE_FAIL;
- break;
- }
-
- run->mmio.len = bytes;
- run->mmio.is_write = 0;
- vcpu->mmio_is_write = 0;
-
- if (op == lb_op)
- vcpu->mmio_needed = 2;
- else
- vcpu->mmio_needed = 1;
-
+ run->mmio.len = 1;
break;
default:
kvm_err("Load not yet supported (inst=0x%08x)\n",
inst.word);
- er = EMULATE_FAIL;
- break;
+ vcpu->mmio_needed = 0;
+ return EMULATE_FAIL;
}
- return er;
+ run->mmio.is_write = 0;
+ vcpu->mmio_is_write = 0;
+ return EMULATE_DO_MMIO;
}
static enum emulation_result kvm_mips_guest_cache_op(int (*fn)(unsigned long),
@@ -1873,18 +1779,6 @@ enum emulation_result kvm_mips_emulate_inst(u32 cause, u32 *opc,
case cop0_op:
er = kvm_mips_emulate_CP0(inst, opc, cause, run, vcpu);
break;
- case sb_op:
- case sh_op:
- case sw_op:
- er = kvm_mips_emulate_store(inst, cause, run, vcpu);
- break;
- case lb_op:
- case lbu_op:
- case lhu_op:
- case lh_op:
- case lw_op:
- er = kvm_mips_emulate_load(inst, cause, run, vcpu);
- break;
#ifndef CONFIG_CPU_MIPSR6
case cache_op:
--
git-series 0.8.10
