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KVM: Portability: Move x86 emulation and mmio device hook to x86.c
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This patch moves the following functions to from kvm_main.c to x86.c:
emulator_read/write_std, vcpu_find_pervcpu_dev, vcpu_find_mmio_dev,
emulator_read/write_emulated, emulator_write_phys,
emulator_write_emulated_onepage, emulator_cmpxchg_emulated,
get_setment_base, emulate_invlpg, emulate_clts, emulator_get/set_dr,
kvm_report_emulation_failure, emulate_instruction

The following data type is moved to x86.c:
struct x86_emulate_ops emulate_ops

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
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Carsten Otte authored and Avi Kivity committed Jan 30, 2008
1 parent 15c4a64 commit bbd9b64
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Showing 2 changed files with 358 additions and 357 deletions.
357 changes: 0 additions & 357 deletions drivers/kvm/kvm_main.c
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Original file line number Diff line number Diff line change
Expand Up @@ -827,369 +827,12 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
}
}

int emulator_read_std(unsigned long addr,
void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
void *data = val;

while (bytes) {
gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);
unsigned offset = addr & (PAGE_SIZE-1);
unsigned tocopy = min(bytes, (unsigned)PAGE_SIZE - offset);
int ret;

if (gpa == UNMAPPED_GVA)
return X86EMUL_PROPAGATE_FAULT;
ret = kvm_read_guest(vcpu->kvm, gpa, data, tocopy);
if (ret < 0)
return X86EMUL_UNHANDLEABLE;

bytes -= tocopy;
data += tocopy;
addr += tocopy;
}

return X86EMUL_CONTINUE;
}
EXPORT_SYMBOL_GPL(emulator_read_std);

static int emulator_write_std(unsigned long addr,
const void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
pr_unimpl(vcpu, "emulator_write_std: addr %lx n %d\n", addr, bytes);
return X86EMUL_UNHANDLEABLE;
}

/*
* Only apic need an MMIO device hook, so shortcut now..
*/
static struct kvm_io_device *vcpu_find_pervcpu_dev(struct kvm_vcpu *vcpu,
gpa_t addr)
{
struct kvm_io_device *dev;

if (vcpu->apic) {
dev = &vcpu->apic->dev;
if (dev->in_range(dev, addr))
return dev;
}
return NULL;
}

static struct kvm_io_device *vcpu_find_mmio_dev(struct kvm_vcpu *vcpu,
gpa_t addr)
{
struct kvm_io_device *dev;

dev = vcpu_find_pervcpu_dev(vcpu, addr);
if (dev == NULL)
dev = kvm_io_bus_find_dev(&vcpu->kvm->mmio_bus, addr);
return dev;
}

static struct kvm_io_device *vcpu_find_pio_dev(struct kvm_vcpu *vcpu,
gpa_t addr)
{
return kvm_io_bus_find_dev(&vcpu->kvm->pio_bus, addr);
}

static int emulator_read_emulated(unsigned long addr,
void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
struct kvm_io_device *mmio_dev;
gpa_t gpa;

if (vcpu->mmio_read_completed) {
memcpy(val, vcpu->mmio_data, bytes);
vcpu->mmio_read_completed = 0;
return X86EMUL_CONTINUE;
}

gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);

/* For APIC access vmexit */
if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
goto mmio;

if (emulator_read_std(addr, val, bytes, vcpu)
== X86EMUL_CONTINUE)
return X86EMUL_CONTINUE;
if (gpa == UNMAPPED_GVA)
return X86EMUL_PROPAGATE_FAULT;

mmio:
/*
* Is this MMIO handled locally?
*/
mmio_dev = vcpu_find_mmio_dev(vcpu, gpa);
if (mmio_dev) {
kvm_iodevice_read(mmio_dev, gpa, bytes, val);
return X86EMUL_CONTINUE;
}

vcpu->mmio_needed = 1;
vcpu->mmio_phys_addr = gpa;
vcpu->mmio_size = bytes;
vcpu->mmio_is_write = 0;

return X86EMUL_UNHANDLEABLE;
}

static int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
const void *val, int bytes)
{
int ret;

ret = kvm_write_guest(vcpu->kvm, gpa, val, bytes);
if (ret < 0)
return 0;
kvm_mmu_pte_write(vcpu, gpa, val, bytes);
return 1;
}

static int emulator_write_emulated_onepage(unsigned long addr,
const void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
struct kvm_io_device *mmio_dev;
gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);

if (gpa == UNMAPPED_GVA) {
kvm_x86_ops->inject_page_fault(vcpu, addr, 2);
return X86EMUL_PROPAGATE_FAULT;
}

/* For APIC access vmexit */
if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
goto mmio;

if (emulator_write_phys(vcpu, gpa, val, bytes))
return X86EMUL_CONTINUE;

mmio:
/*
* Is this MMIO handled locally?
*/
mmio_dev = vcpu_find_mmio_dev(vcpu, gpa);
if (mmio_dev) {
kvm_iodevice_write(mmio_dev, gpa, bytes, val);
return X86EMUL_CONTINUE;
}

vcpu->mmio_needed = 1;
vcpu->mmio_phys_addr = gpa;
vcpu->mmio_size = bytes;
vcpu->mmio_is_write = 1;
memcpy(vcpu->mmio_data, val, bytes);

return X86EMUL_CONTINUE;
}

int emulator_write_emulated(unsigned long addr,
const void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
/* Crossing a page boundary? */
if (((addr + bytes - 1) ^ addr) & PAGE_MASK) {
int rc, now;

now = -addr & ~PAGE_MASK;
rc = emulator_write_emulated_onepage(addr, val, now, vcpu);
if (rc != X86EMUL_CONTINUE)
return rc;
addr += now;
val += now;
bytes -= now;
}
return emulator_write_emulated_onepage(addr, val, bytes, vcpu);
}
EXPORT_SYMBOL_GPL(emulator_write_emulated);

static int emulator_cmpxchg_emulated(unsigned long addr,
const void *old,
const void *new,
unsigned int bytes,
struct kvm_vcpu *vcpu)
{
static int reported;

if (!reported) {
reported = 1;
printk(KERN_WARNING "kvm: emulating exchange as write\n");
}
return emulator_write_emulated(addr, new, bytes, vcpu);
}

static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
{
return kvm_x86_ops->get_segment_base(vcpu, seg);
}

int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address)
{
return X86EMUL_CONTINUE;
}

int emulate_clts(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->set_cr0(vcpu, vcpu->cr0 & ~X86_CR0_TS);
return X86EMUL_CONTINUE;
}

int emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long *dest)
{
struct kvm_vcpu *vcpu = ctxt->vcpu;

switch (dr) {
case 0 ... 3:
*dest = kvm_x86_ops->get_dr(vcpu, dr);
return X86EMUL_CONTINUE;
default:
pr_unimpl(vcpu, "%s: unexpected dr %u\n", __FUNCTION__, dr);
return X86EMUL_UNHANDLEABLE;
}
}

int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long value)
{
unsigned long mask = (ctxt->mode == X86EMUL_MODE_PROT64) ? ~0ULL : ~0U;
int exception;

kvm_x86_ops->set_dr(ctxt->vcpu, dr, value & mask, &exception);
if (exception) {
/* FIXME: better handling */
return X86EMUL_UNHANDLEABLE;
}
return X86EMUL_CONTINUE;
}

void kvm_report_emulation_failure(struct kvm_vcpu *vcpu, const char *context)
{
static int reported;
u8 opcodes[4];
unsigned long rip = vcpu->rip;
unsigned long rip_linear;

rip_linear = rip + get_segment_base(vcpu, VCPU_SREG_CS);

if (reported)
return;

emulator_read_std(rip_linear, (void *)opcodes, 4, vcpu);

printk(KERN_ERR "emulation failed (%s) rip %lx %02x %02x %02x %02x\n",
context, rip, opcodes[0], opcodes[1], opcodes[2], opcodes[3]);
reported = 1;
}
EXPORT_SYMBOL_GPL(kvm_report_emulation_failure);

struct x86_emulate_ops emulate_ops = {
.read_std = emulator_read_std,
.write_std = emulator_write_std,
.read_emulated = emulator_read_emulated,
.write_emulated = emulator_write_emulated,
.cmpxchg_emulated = emulator_cmpxchg_emulated,
};

int emulate_instruction(struct kvm_vcpu *vcpu,
struct kvm_run *run,
unsigned long cr2,
u16 error_code,
int no_decode)
{
int r;

vcpu->mmio_fault_cr2 = cr2;
kvm_x86_ops->cache_regs(vcpu);

vcpu->mmio_is_write = 0;
vcpu->pio.string = 0;

if (!no_decode) {
int cs_db, cs_l;
kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);

vcpu->emulate_ctxt.vcpu = vcpu;
vcpu->emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
vcpu->emulate_ctxt.cr2 = cr2;
vcpu->emulate_ctxt.mode =
(vcpu->emulate_ctxt.eflags & X86_EFLAGS_VM)
? X86EMUL_MODE_REAL : cs_l
? X86EMUL_MODE_PROT64 : cs_db
? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;

if (vcpu->emulate_ctxt.mode == X86EMUL_MODE_PROT64) {
vcpu->emulate_ctxt.cs_base = 0;
vcpu->emulate_ctxt.ds_base = 0;
vcpu->emulate_ctxt.es_base = 0;
vcpu->emulate_ctxt.ss_base = 0;
} else {
vcpu->emulate_ctxt.cs_base =
get_segment_base(vcpu, VCPU_SREG_CS);
vcpu->emulate_ctxt.ds_base =
get_segment_base(vcpu, VCPU_SREG_DS);
vcpu->emulate_ctxt.es_base =
get_segment_base(vcpu, VCPU_SREG_ES);
vcpu->emulate_ctxt.ss_base =
get_segment_base(vcpu, VCPU_SREG_SS);
}

vcpu->emulate_ctxt.gs_base =
get_segment_base(vcpu, VCPU_SREG_GS);
vcpu->emulate_ctxt.fs_base =
get_segment_base(vcpu, VCPU_SREG_FS);

r = x86_decode_insn(&vcpu->emulate_ctxt, &emulate_ops);
if (r) {
if (kvm_mmu_unprotect_page_virt(vcpu, cr2))
return EMULATE_DONE;
return EMULATE_FAIL;
}
}

r = x86_emulate_insn(&vcpu->emulate_ctxt, &emulate_ops);

if (vcpu->pio.string)
return EMULATE_DO_MMIO;

if ((r || vcpu->mmio_is_write) && run) {
run->exit_reason = KVM_EXIT_MMIO;
run->mmio.phys_addr = vcpu->mmio_phys_addr;
memcpy(run->mmio.data, vcpu->mmio_data, 8);
run->mmio.len = vcpu->mmio_size;
run->mmio.is_write = vcpu->mmio_is_write;
}

if (r) {
if (kvm_mmu_unprotect_page_virt(vcpu, cr2))
return EMULATE_DONE;
if (!vcpu->mmio_needed) {
kvm_report_emulation_failure(vcpu, "mmio");
return EMULATE_FAIL;
}
return EMULATE_DO_MMIO;
}

kvm_x86_ops->decache_regs(vcpu);
kvm_x86_ops->set_rflags(vcpu, vcpu->emulate_ctxt.eflags);

if (vcpu->mmio_is_write) {
vcpu->mmio_needed = 0;
return EMULATE_DO_MMIO;
}

return EMULATE_DONE;
}
EXPORT_SYMBOL_GPL(emulate_instruction);

/*
* The vCPU has executed a HLT instruction with in-kernel mode enabled.
*/
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