if (sscanf(name, "%d:%d:%d:%d", &host, &bus, &target, &lun) != 4)
return NULL;
- /* rebase host offset to get the local relative number */
+ /*
+ * Rebase host offset to get the local relative number
+ *
+ * Note: This is by definition racy, unreliable and too simple.
+ * Please do not copy this model anywhere. It's just a left-over
+ * from the time we had no idea how things should look like in
+ * the end.
+ *
+ * Making assumptions about a global in-kernel counter and use
+ * that to calculate a local offset is a very broken concept. It
+ * can only work as long as things are in strict order.
+ *
+ * The kernel needs to export the instance/port number of a
+ * controller directly, without the need for rebase magic like
+ * this. Manual driver unbind/bind, parallel hotplug/unplug will
+ * get into the way of this "I hope it works" logic.
+ */
basenum = -1;
base = strdup(udev_device_get_syspath(hostdev));
if (base == NULL)
return parent;
}
+static struct udev_device *handle_cciss(struct udev_device *parent, char **path)
+{
+ const char *str;
+ unsigned int controller, disk;
+
+ str = udev_device_get_sysname(parent);
+ if (sscanf(str, "c%ud%u%*s", &controller, &disk) != 2)
+ return NULL;
+
+ path_prepend(path, "cciss-disk%u", disk);
+ parent = skip_subsystem(parent, "cciss");
+ return parent;
+}
+
static void handle_scsi_tape(struct udev_device *dev, char **path)
{
const char *name;
{
struct udev_device *parent;
char *path = NULL;
+ bool some_transport = false;
/* S390 ccw bus */
parent = udev_device_get_parent_with_subsystem_devtype(dev, "ccw", NULL);
handle_scsi_tape(parent, &path);
} else if (strcmp(subsys, "scsi") == 0) {
parent = handle_scsi(parent, &path);
+ some_transport = true;
+ } else if (strcmp(subsys, "cciss") == 0) {
+ parent = handle_cciss(parent, &path);
+ some_transport = true;
} else if (strcmp(subsys, "usb") == 0) {
parent = handle_usb(parent, &path);
+ some_transport = true;
} else if (strcmp(subsys, "serio") == 0) {
path_prepend(&path, "serio-%s", udev_device_get_sysnum(parent));
parent = skip_subsystem(parent, "serio");
} else if (strcmp(subsys, "platform") == 0) {
path_prepend(&path, "platform-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "platform");
+ some_transport = true;
} else if (strcmp(subsys, "acpi") == 0) {
path_prepend(&path, "acpi-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "acpi");
parent = udev_device_get_parent(parent);
}
+
+ /*
+ * Do not return a single-parent-device-only for block
+ * devices, they might have entire buses behind it which
+ * do not get unique IDs only by using the parent device.
+ */
+ if (!some_transport && streq(udev_device_get_subsystem(dev), "block")) {
+ free(path);
+ path = NULL;
+ }
+
out:
if (path != NULL) {
char tag[UTIL_NAME_SIZE];