[PATCH v2 06/22] KVM: x86: cleanup the code of read/write emulation

Xiao Guangrong
2011-06-22T14:30:41Z

Using the read/write operation to remove the same code

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
arch/x86/kvm/x86.c | 149 ++++++++++++++++-----------------------------------
1 files changed, 47 insertions(+), 102 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 887714f..baa5a11 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3965,85 +3965,6 @@ static int vcpu_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
return 0;
}

-static int emulator_read_emulated_onepage(unsigned long addr,
- void *val,
- unsigned int bytes,
- struct x86_exception *exception,
- struct kvm_vcpu *vcpu)
-{
- gpa_t gpa;
- int handled, ret;
-
- if (vcpu->mmio_read_completed) {
- memcpy(val, vcpu->mmio_data, bytes);
- trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
- vcpu->mmio_phys_addr, *(u64 *)val);
- vcpu->mmio_read_completed = 0;
- return X86EMUL_CONTINUE;
- }
-
- ret = vcpu_gva_to_gpa(vcpu, addr, &gpa, exception, false);
-
- if (ret < 0)
- return X86EMUL_PROPAGATE_FAULT;
-
- if (ret)
- goto mmio;
-
- if (!kvm_read_guest(vcpu->kvm, gpa, val, bytes))
- return X86EMUL_CONTINUE;
-
-mmio:
- /*
- * Is this MMIO handled locally?
- */
- handled = vcpu_mmio_read(vcpu, gpa, bytes, val);
-
- if (handled == bytes)
- return X86EMUL_CONTINUE;
-
- gpa += handled;
- bytes -= handled;
- val += handled;
-
- trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, 0);
-
- vcpu->mmio_needed = 1;
- vcpu->run->exit_reason = KVM_EXIT_MMIO;
- vcpu->run->mmio.phys_addr = vcpu->mmio_phys_addr = gpa;
- vcpu->mmio_size = bytes;
- vcpu->run->mmio.len = min(vcpu->mmio_size, 8);
- vcpu->run->mmio.is_write = vcpu->mmio_is_write = 0;
- vcpu->mmio_index = 0;
-
- return X86EMUL_IO_NEEDED;
-}
-
-static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
- unsigned long addr,
- void *val,
- unsigned int bytes,
- struct x86_exception *exception)
-{
- struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-
- /* Crossing a page boundary? */
- if (((addr + bytes - 1) ^ addr) & PAGE_MASK) {
- int rc, now;
-
- now = -addr & ~PAGE_MASK;
- rc = emulator_read_emulated_onepage(addr, val, now, exception,
- vcpu);
- if (rc != X86EMUL_CONTINUE)
- return rc;
- addr += now;
- val += now;
- bytes -= now;
- }
- return emulator_read_emulated_onepage(addr, val, bytes, exception,
- vcpu);
-}
-
int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
const void *val, int bytes)
{
@@ -4128,16 +4049,22 @@ static struct read_write_emulator_ops write_emultor = {
.write = true,
};

-static int emulator_write_emulated_onepage(unsigned long addr,
- const void *val,
- unsigned int bytes,
- struct x86_exception *exception,
- struct kvm_vcpu *vcpu)
+static int emulator_read_write_onepage(unsigned long addr, void *val,
+ unsigned int bytes,
+ struct x86_exception *exception,
+ struct kvm_vcpu *vcpu,
+ struct read_write_emulator_ops *ops)
+
{
- gpa_t gpa;
+ gpa_t gpa;
int handled, ret;
+ bool write = ops->write;
+
+ if (ops->read_write_prepare &&
+ ops->read_write_prepare(vcpu, val, bytes))
+ return X86EMUL_CONTINUE;

- ret = vcpu_gva_to_gpa(vcpu, addr, &gpa, exception, true);
+ ret = vcpu_gva_to_gpa(vcpu, addr, &gpa, exception, write);

if (ret < 0)
return X86EMUL_PROPAGATE_FAULT;
@@ -4146,15 +4073,14 @@ static int emulator_write_emulated_onepage(unsigned long addr,
if (ret)
goto mmio;

- if (emulator_write_phys(vcpu, gpa, val, bytes))
+ if (ops->read_write_emulate(vcpu, gpa, val, bytes))
return X86EMUL_CONTINUE;

mmio:
- trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, *(u64 *)val);
/*
* Is this MMIO handled locally?
*/
- handled = vcpu_mmio_write(vcpu, gpa, bytes, val);
+ handled = ops->read_write_mmio(vcpu, gpa, bytes, val);
if (handled == bytes)
return X86EMUL_CONTINUE;

@@ -4163,23 +4089,20 @@ mmio:
val += handled;

vcpu->mmio_needed = 1;
- memcpy(vcpu->mmio_data, val, bytes);
vcpu->run->exit_reason = KVM_EXIT_MMIO;
vcpu->run->mmio.phys_addr = vcpu->mmio_phys_addr = gpa;
vcpu->mmio_size = bytes;
vcpu->run->mmio.len = min(vcpu->mmio_size, 8);
- vcpu->run->mmio.is_write = vcpu->mmio_is_write = 1;
- memcpy(vcpu->run->mmio.data, vcpu->mmio_data, 8);
+ vcpu->run->mmio.is_write = vcpu->mmio_is_write = write;
vcpu->mmio_index = 0;

- return X86EMUL_CONTINUE;
+ return ops->read_write_exit_mmio(vcpu, gpa, val, bytes);
}

-int emulator_write_emulated(struct x86_emulate_ctxt *ctxt,
- unsigned long addr,
- const void *val,
- unsigned int bytes,
- struct x86_exception *exception)
+int emulator_read_write(struct x86_emulate_ctxt *ctxt, unsigned long addr,
+ void *val, unsigned int bytes,
+ struct x86_exception *exception,
+ struct read_write_emulator_ops *ops)
{
struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);

@@ -4188,16 +4111,38 @@ int emulator_write_emulated(struct x86_emulate_ctxt *ctxt,
int rc, now;

now = -addr & ~PAGE_MASK;
- rc = emulator_write_emulated_onepage(addr, val, now, exception,
- vcpu);
+ rc = emulator_read_write_onepage(addr, val, now, exception,
+ vcpu, ops);
+
if (rc != X86EMUL_CONTINUE)
return rc;
addr += now;
val += now;
bytes -= now;
}
- return emulator_write_emulated_onepage(addr, val, bytes, exception,
- vcpu);
+
+ return emulator_read_write_onepage(addr, val, bytes, exception,
+ vcpu, ops);
+}
+
+static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
+ unsigned long addr,
+ void *val,
+ unsigned int bytes,
+ struct x86_exception *exception)
+{
+ return emulator_read_write(ctxt, addr, val, bytes,
+ exception, &read_emultor);
+}
+
+int emulator_write_emulated(struct x86_emulate_ctxt *ctxt,
+ unsigned long addr,
+ const void *val,
+ unsigned int bytes,
+ struct x86_exception *exception)
+{
+ return emulator_read_write(ctxt, addr, (void *)val, bytes,
+ exception, &write_emultor);
}

#define CMPXCHG_TYPE(t, ptr, old, new) \
--
1.7.5.4