USB: dynamically allocate usb_device children pointers instead of using a fix array

Non-hub device has no child, and even a real USB hub has ports far
less than USB_MAXCHILDREN, so there is no need using a fix array for
child devices, just allocate it dynamically according real port
number.

Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 72c51cd..28664eb 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1047,8 +1047,10 @@ static int hub_configure(struct usb_hub *hub,
        dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
                (hdev->maxchild == 1) ? "" : "s");
 
+       hdev->children = kzalloc(hdev->maxchild *
+                               sizeof(struct usb_device *), GFP_KERNEL);
        hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
-       if (!hub->port_owners) {
+       if (!hdev->children || !hub->port_owners) {
                ret = -ENOMEM;
                goto fail;
        }
@@ -1279,7 +1281,8 @@ static unsigned highspeed_hubs;
 
 static void hub_disconnect(struct usb_interface *intf)
 {
-       struct usb_hub *hub = usb_get_intfdata (intf);
+       struct usb_hub *hub = usb_get_intfdata(intf);
+       struct usb_device *hdev = interface_to_usbdev(intf);
 
        /* Take the hub off the event list and don't let it be added again */
        spin_lock_irq(&hub_event_lock);
@@ -1301,6 +1304,7 @@ static void hub_disconnect(struct usb_interface *intf)
                highspeed_hubs--;
 
        usb_free_urb(hub->urb);
+       kfree(hdev->children);
        kfree(hub->port_owners);
        kfree(hub->descriptor);
        kfree(hub->status);
@@ -1676,7 +1680,7 @@ void usb_disconnect(struct usb_device **pdev)
        usb_lock_device(udev);
 
        /* Free up all the children before we remove this device */
-       for (i = 0; i < USB_MAXCHILDREN; i++) {
+       for (i = 0; i < udev->maxchild; i++) {
                if (udev->children[i])
                        usb_disconnect(&udev->children[i]);
        }

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 0c51663..73b68d1 100644 (file)
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -501,7 +501,7 @@ struct usb_device {
 #endif
 
        int maxchild;
-       struct usb_device *children[USB_MAXCHILDREN];
+       struct usb_device **children;
 
        u32 quirks;
        atomic_t urbnum;