discover/udev: Separate block-specific udev discovery

We'd like to trigger network device discovery from udev code, but most
of the device_add code path assumes block devices.

This change adds a subsystem check, and moves the block-specific code to
udev_handle_block_add.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/udev.c b/discover/udev.c
index 3127ec25edc68dbc1cf484b973f76905c3ae0ebc..e3495e99efe7f6f69ad33ba42dae26c07c2900d6 100644 (file)
--- a/discover/udev.c
+++ b/discover/udev.c
@@ -60,23 +60,17 @@ static void udev_setup_device_params(struct udev_device *udev,
                                udev_list_entry_get_value(entry));
 }
 
-static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
+static int udev_handle_block_add(struct pb_udev *udev, struct udev_device *dev,
+               const char *name)
 {
        struct discover_device *ddev;
        const char *typestr;
        const char *uuid;
        const char *path;
-       const char *name;
        const char *node;
        const char *prop;
        bool cdrom;
 
-       name = udev_device_get_sysname(dev);
-       if (!name) {
-               pb_debug("udev_device_get_sysname failed\n");
-               return -1;
-       }
-
        typestr = udev_device_get_devtype(dev);
        if (!typestr) {
                pb_debug("udev_device_get_devtype failed\n");
@@ -107,12 +101,6 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
                }
        }
 
-       /* We have enough info to create the device and start discovery */
-       ddev = device_lookup_by_id(udev->handler, name);
-       if (ddev) {
-               pb_debug("device %s is already present?\n", name);
-               return -1;
-       }
 
        /* We may see multipath devices; they'll have the same uuid as an
         * existing device, so only parse the first. */
@@ -144,6 +132,37 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
        return 0;
 }
 
+static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
+{
+       const char *subsys;
+       const char *name;
+
+       name = udev_device_get_sysname(dev);
+       if (!name) {
+               pb_debug("udev_device_get_sysname failed\n");
+               return -1;
+       }
+
+       subsys = udev_device_get_subsystem(dev);
+       if (!subsys) {
+               pb_debug("udev_device_get_subsystem failed\n");
+               return -1;
+       }
+
+       if (device_lookup_by_id(udev->handler, name)) {
+               pb_debug("device %s is already present?\n", name);
+               return -1;
+       }
+
+       if (!strcmp(subsys, "block")) {
+               return udev_handle_block_add(udev, dev, name);
+       }
+
+       pb_debug("SKIP %s: unknown subsystem %s\n", name, subsys);
+       return -1;
+}
+
+
 static int udev_handle_dev_remove(struct pb_udev *udev, struct udev_device *dev)
 {
        struct discover_device *ddev;