[PATCH 28/28] kvm tools: Create arch-specific kvm_cpu__emulate_io()

[Matt Evans <matt@ozlabs.org>]

Different architectures will deal with MMIO exits differently.  For example,
KVM_EXIT_IO is x86-specific, and I/O cycles are often synthesisted by steering
into windows in PCI bridges on other architectures.

This patch moves the IO/MMIO exit code from the main runloop into x86/kvm-cpu.c

Signed-off-by: Matt Evans <matt@ozlabs.org>
---
 tools/kvm/include/kvm/kvm-cpu.h |    1 +
 tools/kvm/kvm-cpu.c             |   37 +++++--------------------------------
 tools/kvm/x86/kvm-cpu.c         |   37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 43 insertions(+), 32 deletions(-)

diff --git a/tools/kvm/include/kvm/kvm-cpu.h b/tools/kvm/include/kvm/kvm-cpu.h
index 15618f1..6f38c0c 100644
--- a/tools/kvm/include/kvm/kvm-cpu.h
+++ b/tools/kvm/include/kvm/kvm-cpu.h
@@ -13,6 +13,7 @@ void kvm_cpu__run(struct kvm_cpu *vcpu);
 void kvm_cpu__reboot(void);
 int kvm_cpu__start(struct kvm_cpu *cpu);
 bool kvm_cpu__handle_exit(struct kvm_cpu *vcpu);
+bool kvm_cpu__emulate_io(struct kvm_cpu *cpu, struct kvm_run *kvm_run);
 
 int kvm_cpu__get_debug_fd(void);
 void kvm_cpu__set_debug_fd(int fd);
diff --git a/tools/kvm/kvm-cpu.c b/tools/kvm/kvm-cpu.c
index 884a89f..c9fbc81 100644
--- a/tools/kvm/kvm-cpu.c
+++ b/tools/kvm/kvm-cpu.c
@@ -103,49 +103,22 @@ int kvm_cpu__start(struct kvm_cpu *cpu)
 			kvm_cpu__show_registers(cpu);
 			kvm_cpu__show_code(cpu);
 			break;
-		case KVM_EXIT_IO: {
-			bool ret;
-
-			ret = kvm__emulate_io(cpu->kvm,
-					cpu->kvm_run->io.port,
-					(u8 *)cpu->kvm_run +
-					cpu->kvm_run->io.data_offset,
-					cpu->kvm_run->io.direction,
-					cpu->kvm_run->io.size,
-					cpu->kvm_run->io.count);
-
-			if (!ret)
+		case KVM_EXIT_IO:
+		case KVM_EXIT_MMIO:
+			if (!kvm_cpu__emulate_io(cpu, cpu->kvm_run))
 				goto panic_kvm;
 			break;
-		}
-		case KVM_EXIT_MMIO: {
-			bool ret;
-
-			ret = kvm__emulate_mmio(cpu->kvm,
-					cpu->kvm_run->mmio.phys_addr,
-					cpu->kvm_run->mmio.data,
-					cpu->kvm_run->mmio.len,
-					cpu->kvm_run->mmio.is_write);
-
-			if (!ret)
-				goto panic_kvm;
-			break;
-		}
 		case KVM_EXIT_INTR:
 			if (cpu->is_running)
 				break;
 			goto exit_kvm;
 		case KVM_EXIT_SHUTDOWN:
 			goto exit_kvm;
-		default: {
-			bool ret;
-
-			ret = kvm_cpu__handle_exit(cpu);
-			if (!ret)
+		default:
+			if (!kvm_cpu__handle_exit(cpu))
 				goto panic_kvm;
 			break;
 		}
-		}
 		kvm_cpu__handle_coalesced_mmio(cpu);
 	}
 
diff --git a/tools/kvm/x86/kvm-cpu.c b/tools/kvm/x86/kvm-cpu.c
index a0d10cc..665d742 100644
--- a/tools/kvm/x86/kvm-cpu.c
+++ b/tools/kvm/x86/kvm-cpu.c
@@ -217,6 +217,43 @@ bool kvm_cpu__handle_exit(struct kvm_cpu *vcpu)
 	return false;
 }
 
+bool kvm_cpu__emulate_io(struct kvm_cpu *cpu, struct kvm_run *kvm_run)
+{
+	bool ret;
+	switch (kvm_run->exit_reason) {
+	case KVM_EXIT_IO: {
+		ret = kvm__emulate_io(cpu->kvm,
+				      cpu->kvm_run->io.port,
+				      (u8 *)cpu->kvm_run +
+				      cpu->kvm_run->io.data_offset,
+				      cpu->kvm_run->io.direction,
+				      cpu->kvm_run->io.size,
+				      cpu->kvm_run->io.count);
+
+		if (!ret)
+			goto panic_kvm;
+		break;
+	}
+	case KVM_EXIT_MMIO: {
+		ret = kvm__emulate_mmio(cpu->kvm,
+					cpu->kvm_run->mmio.phys_addr,
+					cpu->kvm_run->mmio.data,
+					cpu->kvm_run->mmio.len,
+					cpu->kvm_run->mmio.is_write);
+
+		if (!ret)
+			goto panic_kvm;
+		break;
+	}
+	default:
+		pr_warning("Unknown exit reason %d in %s\n", kvm_run->exit_reason, __FUNCTION__);
+		return false;
+	}
+	return true;
+panic_kvm:
+	return false;
+}
+
 static void print_dtable(const char *name, struct kvm_dtable *dtable)
 {
 	dprintf(debug_fd, " %s                 %016llx  %08hx\n",