vfio/platform: Use vfio_[attach/detach]_device

Let the vfio-platform device use vfio_attach_device() and
vfio_detach_device(), hence hiding the details of the used
IOMMU backend.

Drop the trace event for vfio-platform as we have similar
one in vfio_attach_device.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>

hw/vfio/platform.c

@@ -529,12 +529,7 @@ static VFIODeviceOps vfio_platform_ops = {
  */
 static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp)
 {
-    VFIOGroup *group;
-    VFIODevice *vbasedev_iter;
-    char *tmp, group_path[PATH_MAX], *group_name;
-    ssize_t len;
     struct stat st;
-    int groupid;
     int ret;
 
     /* @sysfsdev takes precedence over @host */
@@ -557,47 +552,15 @@ static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp)
         return -errno;
     }
 
-    tmp = g_strdup_printf("%s/iommu_group", vbasedev->sysfsdev);
-    len = readlink(tmp, group_path, sizeof(group_path));
-    g_free(tmp);
-
-    if (len < 0 || len >= sizeof(group_path)) {
-        ret = len < 0 ? -errno : -ENAMETOOLONG;
-        error_setg_errno(errp, -ret, "no iommu_group found");
-        return ret;
-    }
-
-    group_path[len] = 0;
-
-    group_name = basename(group_path);
-    if (sscanf(group_name, "%d", &groupid) != 1) {
-        error_setg_errno(errp, errno, "failed to read %s", group_path);
-        return -errno;
-    }
-
-    trace_vfio_platform_base_device_init(vbasedev->name, groupid);
-
-    group = vfio_get_group(groupid, &address_space_memory, errp);
-    if (!group) {
-        return -ENOENT;
-    }
-
-    QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
-        if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) {
-            error_setg(errp, "device is already attached");
-            vfio_put_group(group);
-            return -EBUSY;
-        }
-    }
-    ret = vfio_get_device(group, vbasedev->name, vbasedev, errp);
+    ret = vfio_attach_device(vbasedev->name, vbasedev,
+                             &address_space_memory, errp);
     if (ret) {
-        vfio_put_group(group);
         return ret;
     }
 
     ret = vfio_populate_device(vbasedev, errp);
     if (ret) {
-        vfio_put_group(group);
+        vfio_detach_device(vbasedev);
     }
 
     return ret;

hw/vfio/trace-events

@@ -121,7 +121,6 @@ vfio_get_dirty_bitmap(int fd, uint64_t iova, uint64_t size, uint64_t bitmap_size
 vfio_iommu_map_dirty_notify(uint64_t iova_start, uint64_t iova_end) "iommu dirty @ 0x%"PRIx64" - 0x%"PRIx64
 
 # platform.c
-vfio_platform_base_device_init(char *name, int groupid) "%s belongs to group #%d"
 vfio_platform_realize(char *name, char *compat) "vfio device %s, compat = %s"
 vfio_platform_eoi(int pin, int fd) "EOI IRQ pin %d (fd=%d)"
 vfio_platform_intp_mmap_enable(int pin) "IRQ #%d still active, stay in slow path"