[PATCH v5 33/50] multi-process: perform device reset in the remote process

[Jagannathan Raman]

Perform device reset in the remote process when QEMU performs
device reset. This is required to reset the internal state
(like registers, etc...) of emulated devices

Signed-off-by: Elena Ufimtseva <elena.ufimts...@oracle.com>
Signed-off-by: John G Johnson <john.g.john...@oracle.com>
Signed-off-by: Jagannathan Raman <jag.ra...@oracle.com>
---
 V4 -> v5:
  - Device reset wait for remote

 hw/proxy/qemu-proxy.c    | 25 +++++++++++++++++++++++++
 include/io/mpqemu-link.h |  1 +
 remote/remote-main.c     | 14 ++++++++++++++
 3 files changed, 40 insertions(+)

diff --git a/hw/proxy/qemu-proxy.c b/hw/proxy/qemu-proxy.c
index 68517aa..741f02a 100644
--- a/hw/proxy/qemu-proxy.c
+++ b/hw/proxy/qemu-proxy.c
@@ -431,14 +431,39 @@ static void pci_proxy_write_config(PCIDevice *d, uint32_t 
addr, uint32_t val,
     config_op_send(PCI_PROXY_DEV(d), addr, &val, l, PCI_CONFIG_WRITE);
 }
 
+static void proxy_device_reset(DeviceState *dev)
+{
+    PCIProxyDev *pdev = PCI_PROXY_DEV(dev);
+    MPQemuMsg msg;
+    int wait = -1;
+
+    memset(&msg, 0, sizeof(MPQemuMsg));
+
+    msg.bytestream = 0;
+    msg.size = sizeof(msg.data1);
+    msg.cmd = DEVICE_RESET;
+
+    wait = eventfd(0, EFD_CLOEXEC);
+    msg.num_fds = 1;
+    msg.fds[0] = wait;
+
+    mpqemu_msg_send(&msg, pdev->mpqemu_link->com);
+
+    wait_for_remote(wait);
+    close(wait);
+}
+
 static void pci_proxy_dev_class_init(ObjectClass *klass, void *data)
 {
     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     k->realize = pci_proxy_dev_realize;
     k->exit = pci_dev_exit;
     k->config_read = pci_proxy_read_config;
     k->config_write = pci_proxy_write_config;
+
+    dc->reset = proxy_device_reset;
 }
 
 static const TypeInfo pci_proxy_dev_type_info = {
diff --git a/include/io/mpqemu-link.h b/include/io/mpqemu-link.h
index 3962630..d2234ca 100644
--- a/include/io/mpqemu-link.h
+++ b/include/io/mpqemu-link.h
@@ -62,6 +62,7 @@ typedef enum {
     RET_PCI_INFO,
     PROXY_PING,
     MMIO_RETURN,
+    DEVICE_RESET,
     MAX,
 } mpqemu_cmd_t;
 
diff --git a/remote/remote-main.c b/remote/remote-main.c
index 6cfc446..5284ee9 100644
--- a/remote/remote-main.c
+++ b/remote/remote-main.c
@@ -53,8 +53,11 @@
 #include "qemu/log.h"
 #include "qemu/cutils.h"
 #include "remote-opts.h"
+#include "monitor/monitor.h"
+#include "sysemu/reset.h"
 
 static MPQemuLinkState *mpqemu_link;
+
 PCIDevice *remote_pci_dev;
 bool create_done;
 
@@ -241,6 +244,11 @@ fail:
     PUT_REMOTE_WAIT(wait);
 }
 
+static void process_device_reset_msg(MPQemuMsg *msg)
+{
+    qemu_devices_reset();
+}
+
 static int setup_device(MPQemuMsg *msg, Error **errp)
 {
     QObject *obj;
@@ -395,6 +403,12 @@ static void process_msg(GIOCondition cond, MPQemuChannel 
*chan)
         wait = msg->fds[0];
         notify_proxy(wait, (uint32_t)getpid());
         break;
+    case DEVICE_RESET:
+        process_device_reset_msg(msg);
+        if (msg->num_fds == 1) {
+            notify_proxy(msg->fds[0], 0);
+        }
+        break;
     default:
         error_setg(&err, "Unknown command");
         goto finalize_loop;
-- 
1.8.3.1