usb: chipidea: udc: move _ep_queue into an unlocked function

There is no need to call ep_queue unlocked inside the own driver. We
move its functionionality into an unlocked version.

This patch removes potential unlocked timeslots inside
isr_setup_status_phase and isr_get_status_response, in which the lock
got released just before acquired again inside usb_ep_queue.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index 0531532a5c8e1e725ed5eaadba3ee180e0fb625f..ec218b0202c0c3941451d32841be26df8877a0db 100644 (file)
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -642,6 +642,59 @@ static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
        usb_ep_free_request(ep, req);
 }
 
+/**
+ * _ep_queue: queues (submits) an I/O request to an endpoint
+ *
+ * Caller must hold lock
+ */
+static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
+                   gfp_t __maybe_unused gfp_flags)
+{
+       struct ci13xxx_ep  *mEp  = container_of(ep,  struct ci13xxx_ep, ep);
+       struct ci13xxx_req *mReq = container_of(req, struct ci13xxx_req, req);
+       struct ci13xxx *ci = mEp->ci;
+       int retval = 0;
+
+       if (ep == NULL || req == NULL || mEp->ep.desc == NULL)
+               return -EINVAL;
+
+       if (mEp->type == USB_ENDPOINT_XFER_CONTROL) {
+               if (req->length)
+                       mEp = (ci->ep0_dir == RX) ?
+                              ci->ep0out : ci->ep0in;
+               if (!list_empty(&mEp->qh.queue)) {
+                       _ep_nuke(mEp);
+                       retval = -EOVERFLOW;
+                       dev_warn(mEp->ci->dev, "endpoint ctrl %X nuked\n",
+                                _usb_addr(mEp));
+               }
+       }
+
+       /* first nuke then test link, e.g. previous status has not sent */
+       if (!list_empty(&mReq->queue)) {
+               dev_err(mEp->ci->dev, "request already in queue\n");
+               return -EBUSY;
+       }
+
+       if (req->length > 4 * CI13XXX_PAGE_SIZE) {
+               dev_err(mEp->ci->dev, "request bigger than one td\n");
+               return -EMSGSIZE;
+       }
+
+       /* push request */
+       mReq->req.status = -EINPROGRESS;
+       mReq->req.actual = 0;
+
+       retval = _hardware_enqueue(mEp, mReq);
+
+       if (retval == -EALREADY)
+               retval = 0;
+       if (!retval)
+               list_add_tail(&mReq->queue, &mEp->qh.queue);
+
+       return retval;
+}
+
 /**
  * isr_get_status_response: get_status request response
  * @ci: ci struct
@@ -689,9 +742,7 @@ __acquires(mEp->lock)
        }
        /* else do nothing; reserved for future use */
 
-       spin_unlock(mEp->lock);
-       retval = usb_ep_queue(&mEp->ep, req, gfp_flags);
-       spin_lock(mEp->lock);
+       retval = _ep_queue(&mEp->ep, req, gfp_flags);
        if (retval)
                goto err_free_buf;
 
@@ -738,8 +789,6 @@ isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
  * This function returns an error code
  */
 static int isr_setup_status_phase(struct ci13xxx *ci)
-__releases(mEp->lock)
-__acquires(mEp->lock)
 {
        int retval;
        struct ci13xxx_ep *mEp;
@@ -748,9 +797,7 @@ __acquires(mEp->lock)
        ci->status->context = ci;
        ci->status->complete = isr_setup_status_complete;
 
-       spin_unlock(mEp->lock);
-       retval = usb_ep_queue(&mEp->ep, ci->status, GFP_ATOMIC);
-       spin_lock(mEp->lock);
+       retval = _ep_queue(&mEp->ep, ci->status, GFP_ATOMIC);
 
        return retval;
 }
@@ -1128,8 +1175,6 @@ static int ep_queue(struct usb_ep *ep, struct usb_request *req,
                    gfp_t __maybe_unused gfp_flags)
 {
        struct ci13xxx_ep  *mEp  = container_of(ep,  struct ci13xxx_ep, ep);
-       struct ci13xxx_req *mReq = container_of(req, struct ci13xxx_req, req);
-       struct ci13xxx *ci = mEp->ci;
        int retval = 0;
        unsigned long flags;
 
@@ -1137,44 +1182,7 @@ static int ep_queue(struct usb_ep *ep, struct usb_request *req,
                return -EINVAL;
 
        spin_lock_irqsave(mEp->lock, flags);
-
-       if (mEp->type == USB_ENDPOINT_XFER_CONTROL) {
-               if (req->length)
-                       mEp = (ci->ep0_dir == RX) ?
-                              ci->ep0out : ci->ep0in;
-               if (!list_empty(&mEp->qh.queue)) {
-                       _ep_nuke(mEp);
-                       retval = -EOVERFLOW;
-                       dev_warn(mEp->ci->dev, "endpoint ctrl %X nuked\n",
-                                _usb_addr(mEp));
-               }
-       }
-
-       /* first nuke then test link, e.g. previous status has not sent */
-       if (!list_empty(&mReq->queue)) {
-               retval = -EBUSY;
-               dev_err(mEp->ci->dev, "request already in queue\n");
-               goto done;
-       }
-
-       if (req->length > 4 * CI13XXX_PAGE_SIZE) {
-               retval = -EMSGSIZE;
-               dev_err(mEp->ci->dev, "request bigger than one td\n");
-               goto done;
-       }
-
-       /* push request */
-       mReq->req.status = -EINPROGRESS;
-       mReq->req.actual = 0;
-
-       retval = _hardware_enqueue(mEp, mReq);
-
-       if (retval == -EALREADY)
-               retval = 0;
-       if (!retval)
-               list_add_tail(&mReq->queue, &mEp->qh.queue);
-
- done:
+       retval = _ep_queue(ep, req, gfp_flags);
        spin_unlock_irqrestore(mEp->lock, flags);
        return retval;
 }