USB: reorganize urb->status use in dummy-hcd

This patch (as973) reorganizes the way dummy-hcd sets urb->status.  It
now keeps the information in a local variable until the last moment.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/dummy_hcd.c b/drivers/usb/gadget/dummy_hcd.c
index f2b124c..c1af7ba 100644 (file)
--- a/drivers/usb/gadget/dummy_hcd.c
+++ b/drivers/usb/gadget/dummy_hcd.c
@@ -1026,16 +1026,10 @@ static int dummy_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
        return rc;
 }
 
-static void maybe_set_status (struct urb *urb, int status)
-{
-       spin_lock (&urb->lock);
-       urb->status = status;
-       spin_unlock (&urb->lock);
-}
-
 /* transfer up to a frame's worth; caller must own lock */
 static int
-transfer (struct dummy *dum, struct urb *urb, struct dummy_ep *ep, int limit)
+transfer(struct dummy *dum, struct urb *urb, struct dummy_ep *ep, int limit,
+               int *status)
 {
        struct dummy_request    *req;
 
@@ -1103,15 +1097,15 @@ top:
                if (is_short) {
                        if (host_len == dev_len) {
                                req->req.status = 0;
-                               maybe_set_status (urb, 0);
+                               *status = 0;
                        } else if (to_host) {
                                req->req.status = 0;
                                if (dev_len > host_len)
-                                       maybe_set_status (urb, -EOVERFLOW);
+                                       *status = -EOVERFLOW;
                                else
-                                       maybe_set_status (urb, 0);
+                                       *status = 0;
                        } else if (!to_host) {
-                               maybe_set_status (urb, 0);
+                               *status = 0;
                                if (host_len > dev_len)
                                        req->req.status = -EOVERFLOW;
                                else
@@ -1125,9 +1119,8 @@ top:
                                req->req.status = 0;
                        if (urb->transfer_buffer_length == urb->actual_length
                                        && !(urb->transfer_flags
-                                               & URB_ZERO_PACKET)) {
-                               maybe_set_status (urb, 0);
-                       }
+                                               & URB_ZERO_PACKET))
+                               *status = 0;
                }
 
                /* device side completion --> continuable */
@@ -1143,7 +1136,7 @@ top:
                }
 
                /* host side completion --> terminate */
-               if (urb->status != -EINPROGRESS)
+               if (*status != -EINPROGRESS)
                        break;
 
                /* rescan to continue with any other queued i/o */
@@ -1254,6 +1247,7 @@ restart:
                u8                      address;
                struct dummy_ep         *ep = NULL;
                int                     type;
+               int                     status = -EINPROGRESS;
 
                urb = urbp->urb;
                if (urb->unlinked)
@@ -1279,7 +1273,7 @@ restart:
                        dev_dbg (dummy_dev(dum),
                                "no ep configured for urb %p\n",
                                urb);
-                       maybe_set_status (urb, -EPROTO);
+                       status = -EPROTO;
                        goto return_urb;
                }
 
@@ -1294,7 +1288,7 @@ restart:
                        /* NOTE: must not be iso! */
                        dev_dbg (dummy_dev(dum), "ep %s halted, urb %p\n",
                                        ep->ep.name, urb);
-                       maybe_set_status (urb, -EPIPE);
+                       status = -EPIPE;
                        goto return_urb;
                }
                /* FIXME make sure both ends agree on maxpacket */
@@ -1312,7 +1306,7 @@ restart:
                        w_value = le16_to_cpu(setup.wValue);
                        if (le16_to_cpu(setup.wLength) !=
                                        urb->transfer_buffer_length) {
-                               maybe_set_status (urb, -EOVERFLOW);
+                               status = -EOVERFLOW;
                                goto return_urb;
                        }
 
@@ -1342,7 +1336,7 @@ restart:
                                if (setup.bRequestType != Dev_Request)
                                        break;
                                dum->address = w_value;
-                               maybe_set_status (urb, 0);
+                               status = 0;
                                dev_dbg (udc_dev(dum), "set_address = %d\n",
                                                w_value);
                                value = 0;
@@ -1369,7 +1363,7 @@ restart:
                                        if (value == 0) {
                                                dum->devstatus |=
                                                        (1 << w_value);
-                                               maybe_set_status (urb, 0);
+                                               status = 0;
                                        }
 
                                } else if (setup.bRequestType == Ep_Request) {
@@ -1381,7 +1375,7 @@ restart:
                                        }
                                        ep2->halted = 1;
                                        value = 0;
-                                       maybe_set_status (urb, 0);
+                                       status = 0;
                                }
                                break;
                        case USB_REQ_CLEAR_FEATURE:
@@ -1391,7 +1385,7 @@ restart:
                                                dum->devstatus &= ~(1 <<
                                                        USB_DEVICE_REMOTE_WAKEUP);
                                                value = 0;
-                                               maybe_set_status (urb, 0);
+                                               status = 0;
                                                break;
                                        default:
                                                value = -EOPNOTSUPP;
@@ -1406,7 +1400,7 @@ restart:
                                        }
                                        ep2->halted = 0;
                                        value = 0;
-                                       maybe_set_status (urb, 0);
+                                       status = 0;
                                }
                                break;
                        case USB_REQ_GET_STATUS:
@@ -1443,7 +1437,7 @@ restart:
                                        urb->actual_length = min (2,
                                                urb->transfer_buffer_length);
                                        value = 0;
-                                       maybe_set_status (urb, 0);
+                                       status = 0;
                                }
                                break;
                        }
@@ -1470,7 +1464,7 @@ restart:
                                        dev_dbg (udc_dev(dum),
                                                "setup --> %d\n",
                                                value);
-                               maybe_set_status (urb, -EPIPE);
+                               status = -EPIPE;
                                urb->actual_length = 0;
                        }
 
@@ -1487,7 +1481,7 @@ restart:
                         * report random errors, to debug drivers.
                         */
                        limit = max (limit, periodic_bytes (dum, ep));
-                       maybe_set_status (urb, -ENOSYS);
+                       status = -ENOSYS;
                        break;
 
                case PIPE_INTERRUPT:
@@ -1501,12 +1495,12 @@ restart:
                default:
                treat_control_like_bulk:
                        ep->last_io = jiffies;
-                       total = transfer (dum, urb, ep, limit);
+                       total = transfer(dum, urb, ep, limit, &status);
                        break;
                }
 
                /* incomplete transfer? */
-               if (urb->status == -EINPROGRESS)
+               if (status == -EINPROGRESS)
                        continue;
 
 return_urb:
@@ -1517,6 +1511,7 @@ return_urb:
 
                usb_hcd_unlink_urb_from_ep(dummy_to_hcd(dum), urb);
                spin_unlock (&dum->lock);
+               urb->status = status;
                usb_hcd_giveback_urb (dummy_to_hcd(dum), urb);
                spin_lock (&dum->lock);