KVM: x86: cleanup the code of read/write emulation

Using the read/write operation to remove the same code

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 45 insertions, 101 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f5c60a84fcf5..2b76ae3cb501 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4045,85 +4045,6 @@ static int vcpu_mmio_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_mmio_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)
 {
@@ -4208,16 +4129,21 @@ 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;
         int handled, ret;
+        bool write = ops->write;
+
+        if (ops->read_write_prepare &&
+                  ops->read_write_prepare(vcpu, val, bytes))
+                return X86EMUL_CONTINUE;
 
-        ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, true);
+        ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, write);
 
         if (ret < 0)
                 return X86EMUL_PROPAGATE_FAULT;
@@ -4226,15 +4152,14 @@ 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;
 
@@ -4243,23 +4168,20 @@ 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);
 
@@ -4268,16 +4190,38 @@ 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) \