[PATCH v4 31/41] vfio/pci: Extract out a helper vfio_pci_get_pci_hot_reset_info

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

This helper will be used by both legacy and iommufd backends.

No functional changes intended.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/vfio/pci.h |  3 +++
 hw/vfio/pci.c | 54 +++++++++++++++++++++++++++++++++++----------------
 2 files changed, 40 insertions(+), 17 deletions(-)

diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index fba8737ab2..1006061afb 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -218,6 +218,9 @@ void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr);
 
 extern const PropertyInfo qdev_prop_nv_gpudirect_clique;
 
+int vfio_pci_get_pci_hot_reset_info(VFIOPCIDevice *vdev,
+                                    struct vfio_pci_hot_reset_info **info_p);
+
 int vfio_populate_vga(VFIOPCIDevice *vdev, Error **errp);
 
 int vfio_pci_igd_opregion_init(VFIOPCIDevice *vdev,
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index c62c02f7b6..eb55e8ae88 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2445,22 +2445,13 @@ static bool vfio_pci_host_match(PCIHostDeviceAddress *addr, const char *name)
     return (strcmp(tmp, name) == 0);
 }
 
-static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
+int vfio_pci_get_pci_hot_reset_info(VFIOPCIDevice *vdev,
+                                    struct vfio_pci_hot_reset_info **info_p)
 {
-    VFIOGroup *group;
     struct vfio_pci_hot_reset_info *info;
-    struct vfio_pci_dependent_device *devices;
-    struct vfio_pci_hot_reset *reset;
-    int32_t *fds;
-    int ret, i, count;
-    bool multi = false;
+    int ret, count;
 
-    trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
-
-    if (!single) {
-        vfio_pci_pre_reset(vdev);
-    }
-    vdev->vbasedev.needs_reset = false;
+    assert(info_p && !*info_p);
 
     info = g_malloc0(sizeof(*info));
     info->argsz = sizeof(*info);
@@ -2468,24 +2459,53 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
     if (ret && errno != ENOSPC) {
         ret = -errno;
+        g_free(info);
         if (!vdev->has_pm_reset) {
             error_report("vfio: Cannot reset device %s, "
                          "no available reset mechanism.", vdev->vbasedev.name);
         }
-        goto out_single;
+        return ret;
     }
 
     count = info->count;
-    info = g_realloc(info, sizeof(*info) + (count * sizeof(*devices)));
-    info->argsz = sizeof(*info) + (count * sizeof(*devices));
-    devices = &info->devices[0];
+    info = g_realloc(info, sizeof(*info) + (count * sizeof(info->devices[0])));
+    info->argsz = sizeof(*info) + (count * sizeof(info->devices[0]));
 
     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
     if (ret) {
         ret = -errno;
+        g_free(info);
         error_report("vfio: hot reset info failed: %m");
+        return ret;
+    }
+
+    *info_p = info;
+    return 0;
+}
+
+static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
+{
+    VFIOGroup *group;
+    struct vfio_pci_hot_reset_info *info = NULL;
+    struct vfio_pci_dependent_device *devices;
+    struct vfio_pci_hot_reset *reset;
+    int32_t *fds;
+    int ret, i, count;
+    bool multi = false;
+
+    trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
+
+    if (!single) {
+        vfio_pci_pre_reset(vdev);
+    }
+    vdev->vbasedev.needs_reset = false;
+
+    ret = vfio_pci_get_pci_hot_reset_info(vdev, &info);
+
+    if (ret) {
         goto out_single;
     }
+    devices = &info->devices[0];
 
     trace_vfio_pci_hot_reset_has_dep_devices(vdev->vbasedev.name);
 
-- 
2.34.1